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FORD BRONCO -> ELECTRICAL; EEC/PCM, Self-Test, wiring diagrams... -> Electronic Engine Control (EEC); SELF TEST & Diagnostic Trouble Code (DTC), OBD II, etc. -> EEC-IV; SELF TEST & Diagnostic Trouble Code (DTC), Overview, etc.
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Although we initially developed this site for 78-96 Big Broncos, information in many Links also applies to F, E Series & Cars. UPDATE; all Links via web.archive may be down; Copy orig. URL & go to http://replay.waybackmachine.org/ to search for the new archived copy
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EEC IV 5.0L 49 State & High Altitude Calibration Conversion (EEC IV Processor Change) TSB 92-16-9 for 92 Bronco, Econoline, F 150 & F 250
EEC IV Inner Workings, Mustang, Last Revised: 12/16/2002 by T Moss
EEC Processor, MIL On with DTC 173 in Continuous Memory w/Pass Code 111 in KOEO & KOER, Replace EEC TSB 92-18-12 for 91-92 5.8L Bronco, Econoline & F Series
EEC-IV System Has NO Control Over the Following Items; "...Fuel quantity and quality; Damaged or faulty ignition components; Internal Engine Condition - rings, valves, Timing belt, etc.; Starter & Battery Circuit; Dual Hall Sensor; TFI or DIS Module; Distributor condition or function; Camshaft Sensor; Crankshaft Sensor; Ignition or DIS Coil; Engine Governor Module..."
Electronic Modules, Protection From Damage by Static Electricity TSB 88-13-3 for All Light Truck Lines, etc.
Emission Maintenance Warning (EMW) & Inferred Mileage Sensor; for 85-87 model year vehicles,the light will display the word "EMISSIONS"; for 88-89 model yearvehicles, the light will display the words "CHECK ENGINE", TSB 89-22-08 for 85-89 Bronco, F Series & many others
Engine Hesitation/Surge with No DTCS in 5.0 & 5.8 Engines & with DTC 179 in 4.9 Engines TSB 95-2-10 for 91-92 Bronco & 91-94 F & E Series
Explanation of 3-Digit Codes & MIL TSB 92-24-03 for 91-93 Bronco, F Series and Many Others
Ford Fuel Injection and Electronic Engine Control: How to Understand, Service and Modify, 1988-1993 by Charles O. Probst
Malfunction Indicator Light (MIL) Introduction TSB 88-05-07 for 88 Bronco, F series, & all others
Powertrain Electronic Control Strategy Book
Scan Tool Won’t Initiate Self-Tests (solid tone only); E4OD transmission control switch wiring may be misrouted causing a short in the steering column and a blown # 17 fuse for 92-96 in TSB 92-22-5 for 92 Bronco & all Light Trucks
Select A Link:
EEC IV Pin-Outs (Partial) in 88-89 & 90-91 Bronco 4.9; 88-90, 91 & 92-93 Bronco 5.0; 88-91 & 92-93 Bronco 5.8; Looking Into Harness Connectors in Ford Electronic Engine Control Overview, Chapter 12, of Ford Fuel Injection and Electronic Engine Control: How to Understand, Service and Modify, 1988-1993
Source: by Charles O. Probst via yunost.ru
Ford Fuel Injection and Electronic Engine Control: How to Understand, Service and Modify, 1988-1993; Scroll Down on First Page, Click on each Section, then on next page, click on the pdf file; the complete book is over 85MB pdf and can be downloaded @ http://www.yunost.ru/docs/Ford-injectors-book/Book.pdf
Source: by Charles O. Probst via yunost.ru
SELF TEST - COMPREHENSIVE & Connector Location pics, Bronco & Ford; "...The self-test plugs were mounted on the passenger side fender on 1985-86 EFI trucks; The self-test plugs are located along the driver's side fender behind the air filter box on 87-95 EFI trucks..."; miesk5 NOTE; Self-Test Input (STI) is the Pin in the Lt gray Connector and Signal Return Ground (STO/SIGRET) is Pin E in black Connector in 87-95; The engine temperature must be greater than 50°F (10°C) to pass the KOEO Self-Test and greater than 180°F (82°C) to pass the KOER Self-Test. Run it around to heat the engine up and shift thru all gears incl Reverse. Then turn off all accesories/lights, etc. Make sure A/C is off and transmission is in Park (automatic) or in Neutral for a Manual & release clutch. Do Key On Engine Off (KOEO) portion first. Fix any codes from the KOEO test before you do the running test (KOER, key on, engine running). Look Codes up in my broncolinks.com site using the new Search function. .; miesk5 Note; Steve83 advises; "...If the CEL is burned out, connect CEL (C) to a 12V test light, and the light's other terminal to a 12V source on the same vehicle..."
Source: by BroncoJoe19 (Joe) at Ford Bronco Zone Forums
"...There are two types of EEC Self-Tests, Key On Engine Off (KOEO) & Key On Engine Running (KOER). While both of these will test for various "hard faults" that are present when the test is run, the processor continuously monitors various operating parameters whenever the engine is running. If the processor detects a problem, it will store a "Continuous Memory" code and light the MIL. These Continuous Memory codes are put out during KOEO Test after any codes associated with hard faults are output. Codes are displayed by flashing the MIL. They are also output as voltage pulses on the Self-Test Output (STO) circuit in the Self-Test connector. In either Self-Test mode, all codes are output twice and in KOEO, the hard fault codes are separated from the Continuous Memory codes by a "separator" pulse. A technician that is unfamiliar with the EEC Self-Test can mistakenly believe that continuous Memory codes are not present when they really are. He may run KOER Self-Test and get a pass code (111) and not realize that KOEO Self-Test must be run to receive any Continuous Memory codes. He may run KOEO Self-Test while counting MIL flashes and misinterpret the repeated hard fault pass code (111) to mean that Continuous Memory does not contain any codes...." READ MORE; "...The self-test plugs were mounted on the passenger side fender on 1985-86 EFI trucks; The self-test plugs are located along the driver's side fender behind the air filter box on 87-95 EFI trucks..."; miesk5 NOTE; Self-Test Input (STI) is the Pin in the Lt gray Connector and Signal Return Ground (STO/SIGRET) is Pin E in black Connector in 87-95; The engine temperature must be greater than 50°F (10°C) to pass the KOEO Self-Test and greater than 180°F (82°C) to pass the KOER Self-Test. Run it around to heat the engine up and shift thru all gears incl Reverse. Then turn off all accessories/lights, etc. Make sure A/C is off and transmission is in Park (automatic) or in Neutral for a Manual & release clutch. Do Key On Engine Off (KOEO) portion first. On all vehicles equipped with a 4.9L engine, the clutch must be depressed during the KOEO Test. On all vehicles equipped with a 7.3L diesel engine, the throttle must be depressed (WOT) during the entire Key On Engine Off Self-Test. Engine ID codes are issued at the beginning of the KOER Test and are one-digit numbers represented by the number of pulses sent out. During KOER; For gasoline engines, the engine ID code is equal to one-half the number of engine cylinders (i.e. 2 pulses = 4 cylinders). For the 7.3L Diesel engine, the ID code = 5. These codes are used to verify the proper PCM is installed and that the Self-Test has been entered. The Dynamic Response code is a single pulse that occurs 6-20 seconds after the engine identification code. When/if the Dynamic Response code occurs, perform a brief Wide-Open Throttle (WOT). The dynamic response check is used on some applications to verify operation of the TP, MAF, MAP & KS sensors. On vehicles equipped with the Power Steering Pressure (PSP) switch, within 1 to 2 seconds after the ID code, the steering wheel must be turned at least one-half turn and released. The PSP Switch signals the EEC Module when power steering pressure exceeds 350 psi ±50. The engine then increases idle speed to compensate for the additional load. It appears the PSP switch was deleted from the 94 model year. PSP Switch is screwed into the high pressure port of the PS pump(5.0L Only). On vehicles equipped with Brake On/Off (BOO) input (such as E4OD), the brake pedal MUST be depressed and released AFTER the ID Code has been displayed. This tests the ability of the EEC system to detect a change of state in the Brake Lamp Switch. On vehicles equipped with Transmission Control Switch (TCS) such as da E4OD, the switch must be cycled after the ID code has been displayed. This tests the ability of the EEC system to detect a change of state in the TCS. TCS = Transmission Control Indicator Light (TCIL) on E4OD it is also ref to as the OD on/off LED/Switch @ end of tranny gear stalk. see Steve83's Article here on the sequence; Fix any codes from the KOEO test before you do the running test (KOER, key on, engine running). Look Codes up in my broncolinks.com site using the new Search function.
Source: by Ford via miesk5 at home.comcast.net
Check Engine Light (CEL) Overview in 92-96; "...The check engine warning indicator comes on when the electronic engine control system is not working properly. The check engine warning indicator comes on briefly when the ignition switch lock cylinder is turned to ON, and should turn off when the engine starts. If the check engine warning indicator does not come on when the ignition switch lock cylinder is turned to ON or if it comes on while the vehicle is moving, the system is malfunctioning..." read more
Source: by Steve83 (Steve, That dirty old truck) at SuperMotors.net
SELF TEST & DTCs; WITH DIAGRAMS & Connector Location pics, Bronco & Ford; "...The self-test plugs were mounted on the passenger side fender on 1985-86 EFI trucks; The self-test plugs are located along the driver's side fender behind the air filter box on 87-95 EFI trucks..."; miesk5 NOTE; Self-Test Input (STI) is the Pin in the Lt gray Connector and Signal Return Ground (STO/SIGRET) is Pin E in black Connector in 87-95; The engine temperature must be greater than 50°F (10°C) to pass the KOEO Self-Test and greater than 180°F (82°C) to pass the KOER Self-Test. Run it around to heat the engine up and shift thru all gears incl Reverse. Then turn off all accesories/lights, etc. Make sure A/C is off and transmission is in Park (automatic) or in Neutral for a Manual & release clutch. Do Key On Engine Off (KOEO) portion first. Fix any codes from the KOEO test before you do the running test (KOER, key on, engine running). Look Codes up in my broncolinks.com site using the new Search function. .; miesk5 Note; Steve83 advises; "...If the CEL is burned out, connect CEL (C) to a 12V test light, and the light's other terminal to a 12V source on the same vehicle..."
Source: by Ryan M (Fireguy50) at fordfuelinjection.com
SELF TEST - & DTCs; COMPREHENSIVE;"...The self-test plugs were mounted on the passenger side fender on 1985-86 EFI trucks; The self-test plugs are located along the driver's side fender behind the air filter box on 87-95 EFI trucks..."; miesk5 NOTE; Self-Test Input (STI) is the Pin in the Lt gray Connector and Signal Return Ground (STO/SIGRET) is Pin E in black Connector in 87-95; The engine temperature must be greater than 50°F (10°C) to pass the KOEO Self-Test and greater than 180°F (82°C) to pass the KOER Self-Test. Run it around to heat the engine up and shift thru all gears incl Reverse. Then turn off all accesories/lights, etc. Make sure A/C is off and transmission is in Park (automatic) or in Neutral for a Manual & release clutch. Do Key On Engine Off (KOEO) portion first. Fix any codes from the KOEO test before you do the running test (KOER, key on, engine running). Look Codes up in my broncolinks.com site using the new Search function. .; miesk5 Note; Steve83 advises; "...If the CEL is burned out, connect CEL (C) to a 12V test light, and the light's other terminal to a 12V source on the same vehicle..."
Source: by Steve83 (Steve, That dirty old truck) at fordf150.net
Self Test - & KOER Self-Test, How To Run; "...The self-test plugs were mounted on the passenger side fender on 1985-86 EFI trucks; The self-test plugs are located along the driver's side fender behind the air filter box on 87-95 EFI trucks..."; miesk5 NOTE; Self-Test Input (STI) is the Pin in the Lt gray Connector and Signal Return Ground (STO/SIGRET) is Pin E in black Connector in 87-95; The engine temperature must be greater than 50°F (10°C) to pass the KOEO Self-Test and greater than 180°F (82°C) to pass the KOER Self-Test. Run it around to heat the engine up and shift thru all gears incl Reverse. Then turn off all accesories/lights, etc. Make sure A/C is off and transmission is in Park (automatic) or in Neutral for a Manual & release clutch. Do Key On Engine Off (KOEO) portion first. Fix any codes from the KOEO test before you do the running test (KOER, key on, engine running). Look Codes up in my broncolinks.com site using the new Search function. .; miesk5 Note; Steve83 advises; "...If the CEL is burned out, connect CEL (C) to a 12V test light, and the light's other terminal to a 12V source on the same vehicle..."
Source: by Ryan M (Fireguy50) at fordfuelinjection.com
SELF TEST - COMPREHENSIVE & Connector Location pic, Bronco & Ford; "...The self-test plugs were mounted on the passenger side fender on 1985-86 EFI trucks; The self-test plugs are located along the driver's side fender behind the air filter box on 87-95 EFI trucks..."; miesk5 NOTE; Self-Test Input (STI) is the Pin in the Lt gray Connector and Signal Return Ground (STO/SIGRET) is Pin E in black Connector in 87-95; The engine temperature must be greater than 50°F (10°C) to pass the KOEO Self-Test and greater than 180°F (82°C) to pass the KOER Self-Test. Run it around to heat the engine up and shift thru all gears incl Reverse. Then turn off all accesories/lights, etc. Make sure A/C is off and transmission is in Park (automatic) or in Neutral for a Manual & release clutch. Do Key On Engine Off (KOEO) portion first. Fix any codes from the KOEO test before you do the running test (KOER, key on, engine running). Look Codes up in my broncolinks.com site using the new Search function. .; miesk5 Note; Steve83 advises; "...If the CEL is burned out, connect CEL (C) to a 12V test light, and the light's other terminal to a 12V source on the same vehicle..."
Source: by dabranco at FSB
2 Digit to 3 Digit "...Ford went from two-digit to three-digit EEC IV Self-Test codes in 1991 to service the increasing number of service codes required to support various government On-Board Diagnostic (OBD) regulations. The phase-in from two-digit to three-digit codes started in the 1991 model year. 1996 Broncos have OBD II that has 3-4 numbers beginning with a Letter; usually a P..."
Source: by Ford via miesk5 at cc
3 Digit Codes & MIL TSB 92-24-03 for 91-93 Bronco, F Series and Many Others
Source: by Ford via Steve83 (Steve, That dirty old truck) at fourdoorbronco.com
Adaptive Control Overview; "...The Adaptive Control system is used to correct changes in engine
Source: by Mike W via Ryan M (Fireguy50) at fordfuelinjection.com
Break-Out Box Overview; \"...The breakout box put itself between the engine and the computer, and allowed the user to rapciously access the information being exchanged. They are simply a pinout board, mounted in a box, with associated cabling, like this... You can see the way the cabling hooks into the computer and then bridges into the automobile system. A closer look at the pinout board, little holes numbered to correspond to the numbered wires in the connector:The output is readable with a high impedance (this is IMPORTANT- Digital Volts Ohmeter (DVOM) No cheap knockoffs here, they may fry the computer by introducing their own voltage.) Not as fancy as a scanner which decodes the meaning for you, but valuable nonetheless because you can always look up every meaning of the output signal somewhere. Like on the factory manual CD or in the manual itself! FORD decided to make maximum use of the breakout box, and designed add ons to allow you to look at other systems. Here for example, is a harness (still looking new in the wrapper) that hooks into all the Distributorless Ignition System (DIS). It connects to the sensor connectors... allowing you full access to the signals, even while the engine is running: TFI (thick film Ignition) Yes there is a cable for this. Mine cost me $15. Here is the diagram ...There was an adapter for the breakout box that read the brake codes, AND... AND... did the procedure for properly bleeding them. It was called the anitlock Brake Adapter (ALA) and looks like this when installed in the unbilical for the breakout box: Betwen $125 and $200 on E-bay. Worth every penny if you want to look inside that engine..."
Source: by Glacier991 (Chris) at explorerforum.com
Capacitor Repair in a 90 5.8
Source: by seedpress (dolittle) at Ford Bronco Zone Forums
Capacitor Repair in a 90 5.8
Source: by dolittle (seedpress) at FSB
Capacitor Repair, Failures Due to Age; "...(A9x and same years ECM's) The patient in question is a remanufactured A9L unit. This ECM is the one from a little notch project I'm working on. It started giving some problems starting up, engine flooding, random hesitation, missing and stalls. I opened up the ECM (the car is running with a A9S unit) after the owner brought it for a checkup.What you see is the typical electrolytic capacitors leak, causing intermittent shorts/opens to the neighboring circuits/components and symptoms as the ones explained. Worst case scenarios with this type of failure, is a permanent no start and permanent damage to the PWB preventing it could be repaired. As soon as I replace the capacitors I'll update with the pictures showing the repairs. The following capacitor does not show any leakage problems however, it will also be replaced as a preventative measure..." read more
Source: by Joel5.0 at sbftech.com
Capacitor, Burnt PCM pic in a 94; "...the capacitors inside burned and leaked on the board. it happened to all of them, one was worse then the others..."
Source: by imlikeojnow (Ken) at FSB
Carburetor & C6 Conversion to EFI/OBD II & EO4D in an 86 351W
Source: by Kurt H at 2bigbroncos.org
Check Engine Light (CEL) Wiring Diagram in a 94 from EVTM
Source: by Mikey350 at SuperMotors.net
Check Engine Light Location & Operation in an 88; "...As soon as you turn the key foreward to start the bronc, the light should come on, then once the truck is started it should come back on for about 3 secs then go out. it\'s actually stealthily hidden not in the guage cluster but in the black info strip on the gear shift side if the dash, just between the upper and lower trim pieces, your abs, low voltage, 4x4 and right signal indicator are there aswell. if the light fails to come on and check, first look closely for a small piece of electrical tape covering the spot where the light should be( the cheapest fix), if not found take the trim piece off and check for a missing bulb( 2nd most common fix) if the bulb is there change it. then it should come on. if the truck doesnt run the light should still come on when you turn the switch to power. if the battery isn't dead..."
Source: by tiresmok at answers.yahoo.com
Connector Location Diagram in 84-86
Source: by Ryan M (Fireguy50) at FSB
Connector Location Diagram in a 90
Source: by SeattleFSB (Seattle FSB) at SuperMotors.net
Connector Location Diagram, Engine Area in 92-93 4.9
Source: by Ford via chiltonlibrary.com
Connector Location in Engine Bay Diagram in a 90 4.9L Page 1
Source: by Seattle FSB (SeattleFSB) at SuperMotors.net
Connector Location pic in a 93
Source: by Steve83 (Steve, That dirty old truck) at SuperMotors.net
Connector Pin Diagram & Overview
Source: by Fireguy50 (Ryan M) at fordfuelinjection.com
Connector Pin Outs, Bronco & Ford Truck & Van: 4.9, 460, 5.0, 5.8; miesk5 Note, see his Connector Pin Diagram Link above)
Source: by Ryan M (Fireguy50) at fordfuelinjection.com
Connector Pin Outs, Bronco & Ford Truck Wiring Diagram in a 94 from EVTM
Source: by Mikey350 at SuperMotors.net
Connector Pin, Disconnecting
Source: by Ryan M (Fireguy50) at fordfuelinjection.com
Connector Pin-Out Diagram in a 90 5.0 & 5.8
Source: by Ford via subford (Bill K) at photobucket
Connector Re-Pin/Repair Video
Source: by pfun41 at youtube.com
Connector, 10-pin Re-Pin/Repair; "...The “ten pin” connectors are these salt and pepper shaker looking things found at the back of 5.0L engines -between the intake manifold and firewall. These connectors are notorious for developing poor connections and causing strange EEC quirks, like idle fluctuations, intermittent drivability problems, and unexplainable diagnostic codes to be triggered. Ford issued recall 91E19 on 3/27/1992 just for this problem, and created an “extension harness”, assuming the original harness was too short causing the large connectors to pull apart. The real cure for this problem is cleaning and re-shaping the electrical terminals inside the connectors. You should consider doing this as preventative maintenance even if you don’t have problems yet..." read more
Source: by Ryan M (Fireguy50) at fordfuelinjection.com
Connectors, Ten Pin; "...These connectors are notorious for developing poor connections and causing strange EEC quirks, like idle fluctuations, check engine lights, & unexplainable diagnostic codes to be triggered..."
Source: by FORDMUSCLE
Cylinder Balance Test; "...NOTE: This test is only available on 95 Bronco w/1995 CA/MAF/SFI PCM (BIO0) & 96 Bronco; & Sequential Fuel Injection (SFI) Engines. Start an engine running test and press the accelerator lightly within 2 minutes after the last code is output. The PCM will cancel each cylinder in turn and measure the RPM drop. If any weak cylinders are noted their number will be output as a multiple of 10 (e.g. 30, 40). The output is the actual cylinder number, not the number in the firing order. NOTE: Will not always pinpoint bad injectors..."
Source: by muscularmustangs.com
Cylinder Balance Test; "...NOTE: This test is only available on 95 Bronco w/1995 CA/MAF/SFI PCM (BIO0) & 96 Bronco; & Sequential Fuel Injection (SFI) Engines. This test checks all the cylinders in the engine for matched compression ratios. The Cylinder Balance test is designed to help isolate cylinders that have low compression ratios with respect to the others in the engine. This test is performed immediately after the KOER test has finished displaying codes.."
Source: by Christopher I at The Corral corral.net
Cylinder Balance Test; NOTE: This test is only available on 95 Bronco w/1995 CA/MAF/SFI PCM (BIO0) & 96 Bronco; & Sequential Fuel Injection (SFI) Engines
Source: by SigEpBlue (Steve) & Bronco4Life at FSB
Cylinder Balance Test; NOTE: This test is only available on 95 Bronco w/1995 CA/MAF/SFI PCM (BIO0) & 96 Bronco; & Sequential Fuel Injection (SFI) Engines. "...The Cylinder Balance test on the 5.0L SEFI and 5.0L SEFI MA vehicles is designed to aid in the detection of a noncontributing cylinder. The Cylinder Balance test, first reads engine rpm, with all injectors activated. Next, each injector is turned "off and on," one at a time. The rpm drop that results, if any, is then read. These two rpm's are compared to verify that the rpm drop was greater than a calibrated level. The Cylinder Balance Test service codes correspond with cylinder number followed by a "O" on a scanner. Example 20 = cyl #2. 1. Perform Engine Running Self-Test. 2. After the last repeated service code is received, wait 5-10 seconds. 3. Lightly depress and release throttle (not wide-open throttle) within two mintutes of the last repeated service code. 4. Cylinder Balance Test will be per formed at the first test level.Test time is approximately three minutes..." read more
Source: by Tomco Inc. tomco-inc.com
Detonation and/or Malfunction Indicator Lamp (MIL) Illumination with DTCs 332, P1407, and/or P1408 May Occur Under Normal Driving Conditions TSB 96-23-4 for Various Cars; Just because the vehicle is not listed in the TSB doesn’t mean you may not have a clogging problem; Figures are missing see Tomco Link Titled, DTC 332, P1407 and P1408 or detonation
Source: by Ford via way2old at fordforum.com
Diagnosis & Troubleshooting, Chapter 10, from Ford Fuel Injection and Electronic Engine Control: How to Understand, Service and Modify, 1988-1993
Source: by Charles O. Probst via yunost.ru
DTC 10 is "...snap throttle is not a code, it is a command- literally telling you to blip the vehicle throttle. Snapping the throttle open is required to run one of the tests. If you don't do it, you get the 538 code..."
Source: by jake at explorerforum.com
DTC 116 Engine coolant temp. higher or lower than expected Possible causes: Low coolant level (ECT), Ambient temperature below 10°C (50°F) (IAT), Faulty harness connector, Faulty sensor
Source: by fordbronco1995 ("JUICE") at FSB
DTC 116 to 118 ECT Troubleshooting & Possible Causes; "...The ECT sensor is a thermistor, basically a resistor that changes voltage accordingly to temperature changes. It provides a reading that's used by the EEC to change fuel delivery at engine startup to reduce emissions and monitors the temperature of the engine. If you see some rust in it clean it by sanding the surface using a fine grit sandpaper, Also check the connector and wiring..."
Source: by allfordmustangs.com
DTC 12 can't control engine RPM high RPM self test; vacuum leak, TB base idle off, idle air valve dirty or bad, EGR stuck open. Check the IAC valve port in TB for Sludge; Suspect throttle body coking.
Source: by miesk5 at FSB
DTC 121, 122, 123, 124, 125 & DTC P0122, P0123 & P1121 in TSB 94-26-4; "...The following is a list of vehicle symptoms which have been associated with the TPS, but can also be related to other vehicle components. Check engine light, Stalls, quits, hesitation/stumble, fast idle; To minimize the replacement of good components, be advised that the following non-EEC areas may be the issue: Excessive blow-by, PCV malfunction, Vacuum leaks, Fuel pressure, Throttle sticking or linkage binding. MANY VOLTMETERS WILL AUTOMATICALLY CHANGE RANGES WHEN MEASURING TPS OUTPUT FROM IDLE TO WOT. WHEN A VOLTMETER IS USED TO MEASURE TPS OUTPUT FROM IDLE TO WOT, THE METER SCALES OR CHANGES RANGES AUTOMATICALLY. THERE MAY BE AN ERRONEOUS METER DISPLAY UNTIL THE VOLTMETER HAS LOCKED TO THE APPROPRIATE VOLTAGE READING. THE ERRONEOUS METER DISPLAY DOES NOT REPRESENT A DEFECTIVE TPS. NOTE: IT IS RECOMMENDED THAT THE "RANGE LOCK" FEATURE ON MANY METERS BE SET FOR CHECKING TPS VOLTAGE..."
Source: by Ford via tccoa.com
DTC 121, 122, 123, 124, 125 & DTC P0122, P0123 & P1121 in TSB 94-26-4; "...The following is a list of vehicle symptoms which have been associated with the TPS, but can also be related to other vehicle components. Check engine light, Stalls, quits, hesitation/stumble, fast idle; To minimize the replacement of good components, be advised that the following non-EEC areas may be the issue: Excessive blow-by, PCV malfunction, Vacuum leaks, Fuel pressure, Throttle sticking or linkage binding. MANY VOLTMETERS WILL AUTOMATICALLY CHANGE RANGES WHEN MEASURING TPS OUTPUT FROM IDLE TO WOT. WHEN A VOLTMETER IS USED TO MEASURE TPS OUTPUT FROM IDLE TO WOT, THE METER SCALES OR CHANGES RANGES AUTOMATICALLY. THERE MAY BE AN ERRONEOUS METER DISPLAY UNTIL THE VOLTMETER HAS LOCKED TO THE APPROPRIATE VOLTAGE READING. THE ERRONEOUS METER DISPLAY DOES NOT REPRESENT A DEFECTIVE TPS. NOTE: IT IS RECOMMENDED THAT THE "RANGE LOCK" FEATURE ON MANY METERS BE SET FOR CHECKING TPS VOLTAGE..."
Source: by Ford via Chilton
DTC 126-129, P0235-P0237; "...On gasoline engines, the manifold absolute pressure (MAP) sensor senses atmospheric pressure to produce an electrical signal. The frequency of this signal varies with intake manifold pressure. The powertrain control module monitors this signal to determine altitude. The PCM then adjusts the E4OD shift schedule and EPC pressure for altitude. On diesel engines, the MAP sensor measures boost pressure. The PCM monitors this signal and adjusts EPC pressure. Symptoms: Firm shift feel, late shifts at altitude..."
Source: by Ford via Steve83 (Steve, That dirty old truck) at SuperMotors.net
DTC 129 indicates insufficient MAF change during Dynamic Response Test; Possible causes: Open MAF circuit. Open VPWR circuit to MAF sensor. Open PWR GND circuit to MAF sensor. Open MAF RTN circuit to MAF sensor. MAF circuit shorted to ground. Damaged MAF sensor. Air leak before or after MAF sensor. MAF sensor disconnected. Idle Air Control (IAC) system (possible closed throttle position indication). Damaged Powertrain Control Module (PCM). Read more for Pin-Point Testing
Source: by Brian at justanswer.com
DTC 13 Cannot control RPM during ER Self-Test, low RPM & Possible Causes; "...vacuum leak, use garden hose section to listen for leak noise; TB base idle off- Idle Air Control (IAC) Sludge; Poor Idle TSB 91-25-07 for 85-92 Bronco & F Series & many others; air bypass valve dirty or bad..." READ MORE
Source: by miesk5 at FSB
DTC 136 Left front Heated Oxygen Sensor (HO2S) lean Possible Causes: Fuel injectors, HO2S, Secondary Air Injection (AIR) system, Positive Crankcase Ventilation (PCV) /Hose, Vacuum, Evaporative Cannister Purge, Manifold Absolute Pressure (MAP) sensor, Electronic Ignition Coil Failure
Source: by fordbronco1995 ("JUICE") at FSB
DTC 136, 137, 139, 144 and 171 through 178; Oxygen Sensor Troubleshooting & Possible Causes
Source: by GTRaptor at allfordmustangs.com
DTC 14 & 18; Profile Ignition Pickup (PIP) & Troubleshooting; "...The top three leads (for PIP signal) can lose continuity with the back plate (ground) on the module when the unit is hot. You should consider a remote mounted TFI. If your TFI is failing from heat, it can give off computer codes 14 (PIP) and 18 (SPOUT). stalling/dieing or sputtering when hot but runs when it cools off. This can be caused by a faulty TFI and the biggest culprits are heat. Another culprit can be a wire grounding out. Problematic TFI's can give off codes 14 (PIP) and 18 (SPOUT)..." read more
Source: by therangerstation.com
DTC 15 Engine Control Module (ECM, EEC) Failure Symptoms, & other makes (part ad); DTC 15 Engine Control Module (ECM, EEC) Failure; "...Check voltage and ground at ECM connector. Voltage should be no more than 0.5 volts less than the battery voltage. Remove the ECM fuse. A digital volt ohm meter (dvom) or “Hot box” must be used to check all relays, solenoids, and injectors for short circuits. A short circuit will destroy the new ECM and will void the warranty. Check engine harnesses and connectors for corrosion and damage. Wiggle cables while car is running to see if a fault occurs. Power must always be off before beginning any work on the ECM. Symptoms of ECM Failure: No start/hard start; Engine stalling; Check engine light on; Erratic idle speeds; Rough idle / engine surging..."
Source: by CARDONE® cardone.com
DTC 15 No keep Alive Memory power; O = KOEO test key on engine off - No keep Alive Memory power (pin 1) or bad Electronic Control Assembly (EEC, ECA Processor); M = in memory - after separator(10) in KOEO test- Keep Alive Memory (KAM) (pin 1) was interrupted
Source: by Tomco Inc. tomco-inc.com
DTC 15 Pin-Point Testing in an 86
Source: by Various Sources via miesk5 at Ford Bronco Zone Forums
DTC 157 indicates the Mass Air Flow (MAF) sensor signal went below 0.4 volt sometime during the last 80 warm-up cycles. Possible causes: Poor continuity in MAF sensor harness or connectors. Intermittent open or short in MAF sensor or harness. Damaged MAF sensor. Idle Air Control (IAC) system (possible closed throttle position indication). Read more
Source: by miesk5 at FSB
DTC 157 indicates the Mass Air Flow (MAF) sensor signal went below 0.4 volt sometime during the last 80 warm-up cycles. Possible causes: Poor continuity in MAF sensor harness or connectors. Intermittent open or short in MAF sensor or harness. Damaged MAF sensor. Idle Air Control (IAC) system (possible closed throttle position indication). Read more for Pin-Point Testing
Source: by Brian at justanswer.com
DTC 17 RPM below Self-Test limit with Idle Air Control off
Source: by Ford via Ben Watson in How to Tune and Modify Ford Fuel Injection via books.google.com
DTC 172 lean Heated O2; "...Backprobe the MAF (+) and MAF-RTN (-) lines with a DVOM. You should see ~1.0V or slightly less at warm idle. If not, check the +12V and GND lines to make sure there's battery voltage between those terminals with the ignition key turned ON. You also may want to try using the proper spray cleaner on the MAF wires, especially if you have a K&N oily filter (in which case I can almost guarantee there's oily junk on your MAF's wires). Also make certain that the tube(s) leading from the MAF to the throttle body are /100%.jpg intact. The red wire (on the right in the first above picture) is supposed to have battery voltage with the key on. Measure between that wire and the one right next to it. You measure the MAF voltage at idle, because the MAF voltage is what's interpreted by the PCM..."
Source: by SigEpBlue (Steve) at FSB
DTC 172, 173 or 41 for HO2S Failure Or Fuse "E" Inoperative, ABS Light On, Back-Up Lamps Inoperative, Daytime Running Lamp (DRL) Inoperative, MIL On, Inadvertent Self-Test, Speedometer Inoperative & Trailer Battery Charge Relay Inoperative in TSB 95-5-21 for 92-95 Bronco & F Series; "...the HO2S wires in the 12A690 (subassembly of the 14B060 battery cable) harness may become chafed and the vehicle could exhibit any one of the following conditions....Lack of proper HEGO operation may cause, or be the result of a rich or lean fuel condition, which could cause additional heat in the catalyst. Perform self test KOEO and KOER, service any codes. CHECK FOR PROPER HEGO GROUND. If the HEGO ground is good, the following areas may be at fault: ..." READ MORE
Source: by Ford via Steve83 (Steve, That dirty old truck) at SuperMotors.net
DTC 172, 173 or 41 for HO2S Failure Or Fuse "E" Inoperative, ABS Light On, Back-Up Lamps Inoperative, Daytime Running Lamp (DRL) Inoperative, MIL On, Inadvertent Self-Test, Speedometer Inoperative & Trailer Battery Charge Relay Inoperative TSB 95-02-11 for 92-95 Bronco & F Series
Source: by Ford via Chilton
DTC 173 Oxygen sensor not switching - system is or was rich - Single, Right or Rear HO2S; "...I'd guess there's either an obstruction in the exhaust pipe directing the exhaust away from it, preventing it from detecting & operating normally (not likely), OR there may be a fault in the heating element circuit (more likely). It comes off the purple/yellow circuit (can't remember which fuse) which also feed A LOT of other things and runs around the front of the radiator to the R side near the battery where it drops down by the engine mount & goes to the sensor. Make sure you have good power & ground to the appropriate terminals in the connector, and test for a signal voltage. Then, using the old & the new sensors, trace the fault..."
Source: by Steve83 (Steve, That dirty old truck) at forums.off-road.com
DTC 18 IDM circuit failure or SPOUT circuit grounded
Source: by Ford via Ben Watson in How to Tune and Modify Ford Fuel Injection via books.google.com
DTC 18 IDM circuit failure or SPOUT circuit grounded; "...The computer sends out a timing advance correction to the ICM over the SPOUT wire and then looks for the change on the IDM wire. You might check the ECT or the IAT sensor for your problem. Also check the SPOUT/IDM wire going to ground..."
Source: by freeautomechanic.com
DTC 18 or 212; Ignition Diagnostic Monitor (IDM) Troubleshooting; "...Identifying the correct module for your vehicle can be accomplished in a number of ways. First, always refer to the correct application in the Engine Management catalog. If that information is not available, check the wiring of the vehicle. If pin # 4 of the module gets a start signal (which should be battery voltage) from the starter circuit, it's a "Push Start" system. On the other hand, if pin #4 of the module is wired directly to pin #4 of the ECM, then it's a CCD system (refer to diagram #5)..." READ MUCH MORE Miesk5 NOTE; use BLACK Modules in 94-96 Broncos
Source: by Joe D at carquest.com
DTC 181 Right or Rear Rich limit reached; 183 Right or Rear Rich limit reached @ idle; 189 Left or Front Rich limit reached; 192 Left or Front Rich limit reached at idle.These DTCs indicate the system is running lean, although strategy adjusted it to maximum rich; 179 Right or Rear Lean limit reached; 182 Right or Rear Lean limit reached at idle; 188 Left or Front Lean limit reached; 191 Left or Front Lean limit reached at idle. These DTCs indicate that the system is running rich, although strategy adjusted it to Max. lean. Possible Causes & Pin-Pont Testing in a 94 from Ford PCED
Source: by Ford via miesk5 at FSB
DTC 181 Right or Rear Rich limit reached; 183 Right or Rear Rich limit reached @ idle; 189 Left or Front Rich limit reached; 192 Left or Front Rich limit reached at idle.These DTCs indicate the system is running lean, although strategy adjusted it to maximum rich; 179 Right or Rear Lean limit reached; 182 Right or Rear Lean limit reached at idle; 188 Left or Front Lean limit reached; 191 Left or Front Lean limit reached at idle. These DTCs indicate that the system is running rich, although strategy adjusted it to Max. lean. Possible Causes & Pin-Pont Testing in a 94 from Ford PCED
Source: by Ford via thedieselstop.com
DTC 186; "...VISUALLY INSPECT MAF SENSOR This code is usually caused by a vacuum leak. Check for unmetered air between the Mass Air Flow (MAF) sensor and Idle Air Control (IAC) solenoid. Then check all engine vacuum hoses for damage, leaks, cracks, blockage and proper routing. If the vacuum lines check out okay, then it's possible you have a bad MAF or injector(s). Ck the fuel filter. & if all looks good, ck FP
Source: by miesk5 at FSB
DTC 186; "...VISUALLY INSPECT MAF SENSOR, Continuous Memory DTC 184 indicates MAF value is higher than expected. Continuous Memory DTC 185 indicates MAF value is lower than expected. NOTE: If further description is required for the In-Range Test, refer to Quick Test Appendix, �Section 5A�. l Key off. Check for air leaks between IAC solenoid and MAF sensor. l Inspect MAF sensor for oil contamination. -- Excessive blow-by -- PCV malfunction (refer to �Section 14A�). l Are the above checks OK? Yes GO to G9. No SERVICE as necessary. CLEAR Continuous Memory (REFER to Quick Test Appendix, Section 5A). RERUN Quick Test
Source: by Caimanlx93 at wiki.answers.com
DTC 21 ECT out of self test range 0.3 to 3.7 volts
Source: by Ford via Ben Watson in How to Tune and Modify Ford Fuel Injection via books.google.com
DTC 21 ECT out of self test range 0.3 to 3.7 volts; "... ECT is bad, engine not warmed up, bad thermostat, low coolant..Coolant is less than 50 deg F for KOEO, or less than 180 deg F for KOER, or greater than 250 deg F for either. If coolant temp is in proper range, suspect ECT sensor or it's connector/wiring..." read more
Source: by miesk5 at FSB
DTC 21, 51, 61 or 116, 117, 118 "...Failure in either the circuit or temperature sensor will show code 21, 51, 61 or 116, 117, 118.Unplug the harness connector. First, check the signal voltage at the connector with the key on, engine off. Should be approximately 5.0v. Then, check the resistance of the sensor cold. Should be between 58,750 to 40,500 ohms. Plug in the harness connector and warm up the engine to normal operating temperature. Then, unplug and check the resistance of ..." read more
Source: by Seattle FSB (SeattleFSB) at FSB
DTC 211 indicates two successive erratic Profile Ignition Pickup (PIP) pulses occurred, resulting in a possible engine miss or stall. Possible causes: Loose wires/connectors. Arcing secondary ignition components (coil, cap, rotor, wires, plugs, etc.). On-board transmitter (2-way radio).*
Source: by Jim at justanswer.com
DTC 211, P0340, P0341, P0344 & Possible Causes & Repair Procedures for E4OD from 1996 All F-Series and Bronco with E4OD Automatic Transmission Workshop Manual
Source: by Ford via thedieselstop.com
DTC 211; "...code set when the ignition module fails, the pickup coil inside the distributor, or the engine computer. The most common of the three is the coil inside the distributor..."
Source: by RIP at justanswer.com
DTC 211; Hesitation, Stumble, Stall, Miss, No Start, No Spark and/or Diagnostic Trouble Code (DTC) 211 TSB 95-15-11 for 93-95; Shorts in Profile Ignition Pickup (PIP) & Spark Output (SPOUT)
Source: by Ford via Steve83 (Steve, That dirty old truck) at SuperMotors.net
DTC 211; Hesitation, Stumble, Stall, Miss, No Start, No Spark and/or Diagnostic Trouble Code (DTC) 211 TSB 95-15-11 in 93-95 (Shorts in Profile Ignition Pickup (PIP) & Spark Output (SPOUT)
Source: by Ford via justanswer.com
DTC 212 - Ignition module circuit failure-SPOUT circuit grounded; Check to see if the spout connector is good by running a piece of wire where the connector is supposed to go. If that doesn't help any try checking the wiring all the way untill it goes into the connectors.
Source: by NoSlow5oh at allfordmustangs.com
DTC 212 - Loss of IDM input to EEC or SPOUT circuit grounded. Continuous Memory DTC 212 indicates a loss of IDM input to the PCM. Possible causes: -- Open circuit. -- Shorted circuit. -- Damaged ICM. -- Damaged PCM. This is most likely the cause for the tach reading being intermittent as well. Link is gone, saving for info
Source: by driller at Lincolns Of Distinction
DTC 212 indicates a loss of IDM input to the PCM; "...Open harness circuit. Shorted harness circuit. Damaged Ignition Control Module (ICM). Damaged Powertrain Control Module (PCM)..." READ MORE
Source: by Jim at justanswer.com
DTC 212; "...IDM is a feedback signal generated by the ignition system and is monitored at pin #4 of the ECM. Its purpose is to diagnose missed ignition primary pulses at the time the ECM commands the Spout signal to fire the coil. Since it is used solely for diagnostic purposes, if this circuit is not operating properly, it will not affect vehicle driveability; & by Seattle FSB- The Ignition Diagnostic Monitor (IDM) signal is a diagnostic signal for the PCM to to verify a coil firing for each PIP signal. If an erratic or missing IDM signal is received, a Diagnostic Trouble Code (DTC 212) is set. An occasional IDM signal may not affect drivability, but can still throw a trouble code. As SigEpBlue has stated, check for an intermittent ground on the spOUT and/or IDM circuit. Also, ensure that you have the correct Ignition Control Module (ICM) and it is wired correctly to the PCM..."
Source: by SMP via SigEpBlue (Steve) & by Seattle FSB (SeattleFSB) at FSB
DTC 212; "...IDM is a feedback signal generated by the ignition system and is monitored at pin #4 of the ECM. Its purpose is to diagnose missed ignition primary pulses at the time the ECM commands the Spout signal to fire the coil. Since it is used solely for diagnostic purposes, if this circuit is not operating properly, it will not affect vehicle driveability; & by Seattle FSB- The Ignition Diagnostic Monitor (IDM) signal is a diagnostic signal for the PCM to to verify a coil firing for each PIP signal. If an erratic or missing IDM signal is received, a Diagnostic Trouble Code (DTC 212) is set. An occasional IDM signal may not affect drivability, but can still throw a trouble code. As SigEpBlue has stated, check for an intermittent ground on the spOUT and/or IDM circuit. Also, ensure that you have the correct Ignition Control Module (ICM) and it is wired correctly to the PCM..."
Source: by SMP via SigEpBlue (Steve) & by Seattle FSB (SeattleFSB) at FSB
DTC 213 (R) Ignition SPOUT or SAW circuit open or shorted Pin-Point Test; Before proceeding with this Pinpoint Test, verify that the base timing check in Diagnostic Subroutine has been performed. Key off. Disconnect Powertrain Control Module (PCM). Inspect for damaged or pushed out pins, corrosion, loose wires, etc. Service as necessary. PCM disconnected.[/B] (be careful, I hate to touch that connector!) Key on, engine off. Measure voltage between Test Pin 37 and Test Pin 40. Measure voltage between Test Pin 57 and Test Pin 60. Is each voltage greater than 10.5 volts? If not, see DTC 211 in TSB 95-15-11 for possible open/short location
Source: by Ford miesk5 at FSB
DTC 213; "...Code 213 - has a host of possible meanings. The first being as you stated, SPOUT circuit open. Yours obviously is not and you noted the change when you pull the shorting plug. So, this could be an intermittent problem which would need to be troubleshot by clearing Codes and checking to see if it returned. If not, then you may have wiring with sketchy connections. If Code 213 returns immediately, you may have a partial TFI/ICM (grey plastic module on the driver's inner fender in a heat sink between the power distro and the hood spring) issue. The SPOUT signal runs through it before getting all the way back to the ECM. My suggestion would be to replace the TFI/ICM if you still have Code 213 after clearing and retesting and cannot find any obvious wiring faults. The module is engine/model/year specific. I haven't purchased one in a while but before assuming it has failed and since you have intermittent issues, you might do the "wiggle" test. Believe it or not, this is an actual Ford-authorized procedure to check for loose or weak wiring connections. It is carried out much as you might expect. With the truck running, start WIGGLING connections and wiring near and in line with the TFI/ICM module to determine if you can MAKE the problem happen. If so, you can repair the connections or wiring damage. If not, replacing the module may be the last option. They average $90-100 for the Motorcraft units online. You can find less expensive aftermarket units but I don't recommend them simply because reliability can be an issue..."
Source: by greystreak92 (Joe B) at fte
DTC 22 - Manifold Absolute Pressure (MAP)/Barometric Pressure (BARO) sensor is out of Self-Test range. Testing & Diagrams; "...Correct MAP/BARO range of measurement is typically from 1.4 to 1.6 volts...." READ MORE
Source: by miesk5 at Ford Bronco Zone Forums
DTC 22 MAP/BP sensor out of self test range
Source: by Ford via Ben Watson in How to Tune and Modify Ford Fuel Injection via books.google.com
DTC 22 or 126 indicates the Manifold Absolute Pressure (MAP)/Barometric Pressure (BARO) sensor is out of Self-Test range. "...Correct MAP/BARO range of measurement is typically from 1.4 to 1.6 volts; Possible causes: MAP/BARO circuit open between sensor vehicle harness connector and PCM. MAP/BARO circuit shorted to VREF, SIG RTN, or GND. Damaged MAP/BARO sensor. Vacuum trapped at MAP/BARO sensor. High atmospheric pressure. Damaged PCM. VREF circuit open at MAP/BARO sensor. SIG RTN circuit open at MAP/BARO sensor..." Read More
Source: by Brian at justanswer.com
DTC 225 - Knock Sensor (KS) signal not sensed during dynamic response test (ignore if not pinging)
Source: by miesk5 at FSB
DTC 225 - Knock Sensor (KS) signal not sensed during dynamic response test (ignore if not pinging)
Source: by miesk5 at Ford Bronco Zone
DTC 23 Closed throttle TPS voltage higher or lower than expected
Source: by Ford via Ben Watson in How to Tune and Modify Ford Fuel Injection via books.google.com
DTC 23 Throttle Position Sensor (TPS) out of range or throttle set too high; dirty/sticking/ Bad TPS, dirty throttle body, base idle mis-set
Source: by miesk5 at FSB
DTC 24 ACT sensor out of self test range 0.3 to 3.7 volts.
Source: by Ford via Ben Watson in How to Tune and Modify Ford Fuel Injection via books.google.com
DTC 25 Knock not sensed during dynamic test.
Source: by Ford via Ben Watson in How to Tune and Modify Ford Fuel Injection via books.google.com
DTC 25 Knock Sensor not tested (KOER); ignore if not pinging
Source: by miesk5 at FSB
DTC 26 MAF sensor was greater than 0.7 volts with engine off in KOEO; OR, MAF sensor was not between 0.2 and 1.5 volts with engine running in KOER
Source: by Ford via Ben Watson in How to Tune and Modify Ford Fuel Injection via books.google.com
DTC 26, 56, 66 & 76 (part ad); "...Lack of power, spark knock/detonation, buck/jerk, hesitation/surge on acceleration, with or without codes 26, 56, 66 and 76. MAF module failure due to OEM design problem. Road shock causes spot-welded jumper wires inside module to break. Replace with CARDONE MAF unit that comes with a fully repaired module. Each sealed module is opened, protective gel removed, broken jumper wires discarded and new wires soldered into original position. Soldering provides a more secure physical connection while insuring proper electrical contact. The module is tested, any other failed components replaced, protective jell reapplied and finally the module is hermetically sealed. INSTALLER TIP: Check for faulty wiring harness or defective burn-off relay (if applicable) before replacing sensor. Always refer to vehicle service manual for complete test procedures. Ford Technical Service Bulletin 98-23-10 identifies problems with contamination on sensing element causing erratic operation or failure. CARDONE cleans or replaces the sensor element to resolve this TSB..."
Source: by cardone.com
DTC 26, 56, 66, or 76, Mass Air Flow (MAF) Failure Symptoms, Bronco (part ad)
Source: by CARDONE® cardone.com
DTC 27, 29, 452, P0502, P0503, PO716, PO718; Insufficient input from VSS.; "...A more difficult problem to identify is a VSS that works, but sends out the wrong signal for a given vehicle speed. In some cases, a wrong reading from the VSS may still cause a code to be set. For example, if the VSS signal tells the computer the vehicle is traveling 60 miles an hour, but the throttle position sensor and MAP sensor tell the computer that the engine is idling, the computer will be confused. And a confused computer should set any of the following codes: Ford 27, 29, 452. On a vehicle that uses the VSS as a safety device, a defective sensor may send out a wrong "too fast" signal, shutting down fuel flow at the wrong time. Although this doesn’t happen often, it can be a difficult problem to identify. The customer will probably describe it as a random or intermittent sudden loss of power and poor performance, onlyto have the engine resume normal operation. Routine diagnostic checks of the engine in the shop won’t show any problem because there isn’t a problem with the engine or the ECM..." read more
Source: by wellsmfgcorp.com
DTC 29 & 452 Erratic Harsh Shift; PSOM Operates Correctly; "...Continuous Memory DTC 29 indicates that during the last 80 warm-up cycles, the PCM detected an error in the PSOM output signal. DTC 452 indicates the PCM detected an error in the PSOM output signal during the last 40 warm-up cycles. his procedure EXACTLY, from the Ford TSP/PCED..." READ MORE
Source: by SigEpBlue (Steve) at FSB
DTC 31 "... This code could be caused by several different factors. If the pintle position sensor (Ford calls it the EVP sensor) is shorted or open, you could have a code set. If the EGR valve becomes carboned up and does not seat fully, the EVP sensor gives a high reading and a code is set. If the diaphragm of the EGR valve is bad, then it, too, is flagged..."
Source: by Harry G at asashop.org
DTC 31 EGR Valve Position (EVP) Sensor; "...On-Demand codes have been coming up and the voltage on the EVP sensor (EGR valve position sensor that is mounted to the EGR valve) is reading correctly on Fords. The problem seems to be that sometimes the wrong sensors are being installed and are therefore sending the improper voltage signals to the powertrain control module. Ford uses two different EVP sensors: a black and a white (or gray). And both will send a different voltage in the same position. At rest, the black sensor will read .75 to .95 volts and the white (or gray) will read .35 to .45 volts..." read more...
Source: by Dan J at asashop.org
DTC 31 EVP circuit below minimum voltage of 0.24 volts in KOEO & KOER; EVP circuit has intermittently failed below minimum voltage of 0.24 volts in CM = Continues Memory
Source: by Ford via Ben Watson in How to Tune and Modify Ford Fuel Injection via books.google.com
DTC 31 or 32 Both KOEO & KOER EVP sensor out of range EGR is sticking or EVP is bad
Source: by miesk5 at Ford Bronco Zone Forums
DTC 311 - Thermactor air system inoperable. "...The computer determined that for some reason the fresh air injection from the Thermactor system was not present. There are several components that make up this system. The initial component is the smog pump. The first checks I would make are the hoses and plumbing from the smog pump back to the diverter valve (behind the pass. cylinder head) and then on to the crossover pipe at the back of the heads and down to the catalytic converter. The check valves that are at the center of the cross over pipe and the top of the metal tube from the cat are often the culprits as they can and do snap in half as the get old. If the plumbing looks to be in good order we can discuss the slightly more complicated aspects of the system. The diverter valve also has two vacuum lines running to it. Make certain they are in place and intact. (Computer needs to be able to control the flow of fresh air by the Thermactor system)..."
Source: by greystreak92 (Joe B) at fte
DTC 311 - Thermactor air system inoperable; "...because of the possibility that (following is an excerpt of a condensed discussion of how a [B]bad TAB[/B]/TAD/vac line DTC 311 ... and so-on problem could cause the rich aroma; Your smog pump... blows fresh clean air up through a hose to the diverter valve. The solenoid next to the diverter valve which has a .... pink little hose plugged into ... it, creates a vacuum (sucking) that opens up the valve, and allows the fresh air to pass through the valve and make it's way to the exhaust, where the cats burn the unburnt gas more efficiently since this all happens during "open loop mode". Open loop mode happens when you turn on your car and it revs at 1200rpms for the first 15-20 seconds. During this process, your ECU feeds more gas to the engine to warm up the car quickly before driving. (also known as choke on older cars). During this open loop procedure, the extra unburnt gasoline will usually cause your exhaust to smell very rich, and the air that this diverter valve sends to the cats, causes it to burn the extra unburnt gas more efficiently like I mentoined above...thus eliminating the rich gasoline smell that us older mustangs sometimes suffer from..."
Source: by 006 (Speedconcepts) via miesk5 at FSB
DTC 311, 312, 313 & 314; "...311 and 314 indicate the Secondary Air Injection system is inoperative. DTC 312 indicates that Secondary Air is misdirected. DTC 313 indicates that Secondary Air is not being bypassed when requested. Possible causes: Visually inspect vacuum lines for disconnects in the AIR system. Visually inspect for proper vacuum line routing. Refer to VECI decal. Visually inspect Air Pump for broken or loose Air Pump Belt. Refer to Section 13A for adjustment/replacement..." READ MUCH MORE
Source: by Jim at justanswer.com
DTC 312 Secondary Air Injection (AIR) misdirected during KOER Troubleshooting from Ford Bronco PCED/EVTM
Source: by miesk5 at FSB
DTC 313 indicates that Secondary Air is not being bypassed when requested from Ford PCED/EVTM; Possible causes: Vacuum hoses damaged. AIRB/AIRD valve inoperative. Air pump inoperative. AIRB/AIRD solenoids damaged. Visually inspect vacuum lines for disconnects in the AIR system. Visually inspect for proper vacuum line routing. Refer to VECI decal. Visually inspect Air Pump for broken or loose Air Pump Belt. Refer to Section 13A for adjustment/replacement. Were any problems found? YES, SERVICE as necessary. RERUN Quick Test. NO, to KC2 . READ MORE
Source: by Jim at justanswer.com
DTC 32 Air Bag, Driver Side Air Bag Circuit High Resistance or Open; "...indicates that the driver's side airbag circuit has high resistance or is open. In simpler terms, there may be a broken wire. This problem may have some relationship to the horn and cruise control failure that your experiencing as well. Has any work been performed on the steering column or under the dash of your vehicle? In either case, you should have the problem checked out. If the wrong wires get crossed with the airbag wires you could be in for a sudden surprise..."
Source: by Jim G at alldata.com
DTC 32 EVP circuit below minimum voltage of 0.24 volts in KOEO & KOER; OR, EVP circuit has intermittently failed below minimum voltage of 0.24 volts in CM = Continues Memory
Source: by Ford via Ben Watson in How to Tune and Modify Ford Fuel Injection via books.google.com
DTC 32, Driver Side Air Bag Circuit High Resistance or Open & Testing Advoce
Source: by Steve83 (Steve, That dirty old truck) at FSB
DTC 32, Driver Side Air Bag Circuit High Resistance or Open; "...for a 93 Aerostar, from a Ford PCED/EVTM Service Disc... procedure is similar to Bronco...The diagnostic monitor measures the resistance across pin 10 (Circuit 615, GY/W) and pin 11 (Circuit 614, GY/O) every time the ignition switch is turned to the ON position. Normal resistance across these circuits is between 1.5 and 2.0 ohms. This resistance comes from the air bag itself (approximately 1.0 ohms) and the clockspring windings (approximately 0.25 to 0.5 ohms per winding, two windings in all). If the resistance across these two circuits exceeds 4.0 ohms, this indicates a high resistance and the diagnostic monitor will flash code 32.The connectors for the air bag and the clockspring have metal spring clips that act as shorting bars. These shorting bars are built into the plastic hardshell connectors. The shorting bars are designed to short Circuits 614 and 615 together when the connectors are not mated. Do not attempt to remove the air bag shorting bar and measure the resistance of the air bag..."
Source: by Ford via 96_4wdr at fte
DTC 327 - indicates the Pressure Feedback EGR (PFE) / Differential Pressure Feedback EGR (DPFE) sensor signal is less than the Self-Test minimum value of 0.2 volt. Possible causes: Damaged PFE/DPFE sensor. Open harness circuits. Shorted harness circuits. Damaged Powertrain Control Module (PCM). DTC 335 indicates the Pressure Feedback EGR (PFE) / Differential Pressure Feedback EGR (DPFE) sensor is out of Self-Test range. Possible causes: Damaged PFE/DPFE sensor. Obstructed pressure inlet hose(s). Garage exhaust ventilation system affecting PFE/DPFE sensor operation. DTC 536 indicate that when the brake pedal was depressed and released during the Key On Engine Running (KOER) Self-Test, the Brake On/Off (BOO) signal did not cycle high and low. When Diagnostic Trouble Code (DTC) 521 is received in Key On Engine Running (KOER) , check to see if the vehicle is equipped with PSP switch. If not, disregard servicing DTC 521. Return to Diagnostic Routines to service other DTCs. On the face of it, it seems the PFE/DPFE sensor has gone bad. Of course you should check vacuum lines and electrical connectors to be sure they are properly routed and connected; Note, Trucks never used a Pressure Feedback Exhaust (PFE) Sensor
Source: by autorepair.about.com
DTC 327; "...It's not that the engine problem causes the transmission problem, it's just that engine problems can easily be mistaken for transmission problems. If you have a shudder under load it could be a problem with the converter clutch, or it could be due to a problem with the EGR system causing the engine to misfire under load. If the converter clutch is unlocked and slipping the converter slippage can mask the misfire, and when the converter locks the misfire is noticable because the converter slip is gone. I would definitely take care of the EGR system first since it can cause misfires, and is likely to be much less expensive to repair than a transmission problem..." Page 2
Source: by Baumann Electronic Controls, LLC becontrols.com
DTC 328, 327 or 337 Troubleshooting; Continuous Memory DTC 328 or 327 indicates the EGR valve was closed further than normal or EVP sensor or circuit has failed with an intermittent low voltage sometime during vehicle operation. Continuous Memory DTC 337 indicates the EVP signal to the Powertrain Control Module (PCM) was above the maximum Self-Test limit sometime during vehicle operation. Possible causes: Poor continuity in EVP harness or connectors. Intermittent open or short in EVP sensor or harness. Damaged EVP sensor..." READ MORE
Source: by SigEpBlue (Steve) at FSB
DTC 32: Driver Side Air Bag Circuit High Resistance or Open Pinpoint Test in 1994 Bronco/Econoline/F-Series Service Manual
Source: by Ford via ww2.justanswer.com
DTC 33 & 34 "...DTC 33 is triggered when the EVP sensor is not closing.... To prevent the EGR valve from opening when the engine is cold, the vacuum line to the EGR valve may be connected to a parted vacuum switch or a computer-controlled solenoid. Vacuum is not allowed to pass to the valve until the engine is warm. EGR isn't needed when the engine is cold, only when it is warm and under load. Any of these codes could indicate a faulty EGR valve as well. as well as a problem in the ...vacuum solenoids' Miesk5 note; TAB & TAD; so repair those vac lines 1st..."
Source: by Larry C at aa1car
DTC 33 is triggered when the EVP sensor is not closing; so EZiest & cheapest checks are to inspect & repair/replace repair any bad vac lines. for a <$ vac line test; I pull em off and use the straw sucking test; one finger over one end; includes EVP testing & Links
Source: by miesk5 at FSB
DTC 332 - Insufficient EGR flow detected. "...Atop the EGR valve there is a sensor called the EVP (EGR Valve Position) sensor. It detects movement of the pintle iside the EGR valve. You can apply vacuum to the vacuum barb on the EGR valve and observe through the holes in the casting whether the valve is moving or not. It may just be dirty which requires some careful scrubbing and NO SOLVENTS. Otherwise, if the EGR valve is functioning and moving when vacuum is applied, the EVP sensor is suspect and the electrical connections to it should be checked first. (Computer needs to know the EGR valve position for emissions control)..."
Source: by greystreak92 (Joe B) at fte
DTC 332 in a 95; "...CHECK YOUR VACUUM CANISTER; I had this issue for well over a year. I did all my proper checks using the blueprint that Meisk5 gave me. I went through the EVP, manually checked the EGR, all vacuum hose that was pertinent, ETC. removed my vacuum canister to install my new one and this is what I found underneath. I replaced it with this canister (rust bullet applied) from my donor truck and finished it with BlackShell..."
Source: by td 152 at FSB
DTC 332, P1407 and P1408 or detonation ;"...We have run into many situations where a code for insufficient flow has been set and the system is functioning correctly. Then it is time to check the EGR passages. There is a Ford Technical Service Bulletin (TSB 96-23-4) that addresses this for some vehicles. This TSB includes: 1992-1995 Crown Victoria 1994-1995 Thunderbird 1991-1995 Town Car 1992-1995 Grand Marquis 1994-1995 Cougar The concerns have to do with intermittent MILs; DTCs 332, P1407 and P1408; or detonation. If exercising the EGR valve does not result in a change in rpm, then the passages may be clogged. There are “U” shaped passages (Fig. 6) under the throttle body adapter that get clogged with carbon. Remove the adapter, clean the passages and reinstall with a new gasket. Just because the vehicle you are working on is not listed in the TSB doesn’t mean you may not have a clogging problem. Make sure you check the passages and be sure they are clean. Just a slight restriction can cause a flow code to be set, and you may still have an rpm drop that can mislead you..."
Source: by tomco-inc.com
DTC 334 EGR (EVP) closed valve voltage higher than expected; "...Failed sensor, & as by rla2005 (Randy) wrote; carbon between EGR pintle valve and seat holding the valve off its seat. Remove the EGR valve and clean it with carbon remover. Prior to re-installing see if you can blow air through the flange side of the EGR by mouth. the egr is not closing properly which can cause detonation. remove the egr and clean off any carbon built up on it with carb cleaner and a brush if necessary..." read more
Source: by rla2005 (Randy) & miesk5 at FSB
DTC 34 - EGR voltage above closed limit - Failed sensor, carbon between EGR pintle valve and seat holding the valve off its seat. Remove the EGR valve and clean it with carbon remover. Prior to re-installing see if you can blow air through the flange side of the EGR by mouth. the egr is not closing properly which can cause detonation. remove the egr and clean off any carbon built up on it with carb cleaner and a brush if necessary.
Source: by miesk5 at Ford Bronco Zone Forums
DTC 41, 42, 85 OR THREE DIGIT CODES 171, 172, 173, 179, 181, 182, 183 & 565 are received , Check for proper HEGO Ground; in Catalytic Converter Diagnosis TSB 91-12-11 for 86-91 Bronco, F Series, & Econoline
Source: by Ford via Steve83 (Steve, That dirty old truck) at SuperMotors.net
DTC 41, 42, 85 OR THREE DIGIT CODES 171, 172, 173, 179, 181, 182, 183 & 565 are received , Check for proper HEGO Ground; in Catalytic Converter Diagnosis TSB 91-12-11 for 86-91 Bronco, F Series, & Econoline
Source: by Ford via Steve83 (Steve, That dirty old truck) at fourdoorbronco.com
DTC 41, 42, 91, 92, 136, 137,139, 144, 171, 172, 173, 175, 176, 177 & some Possible Causes for Rich & Lean HEGO The engine temperature must be greater than 50°F (10°C) to pass the KOEO Self-Test and greater than 180°F (82°C) to pass the KOER Self-Test. To accomplish this, the engine should be at normal operating temperature
Source: by Ryan M (Fireguy50) at fordfuelinjection.com
DTC 411 Idle speed system not controlling idle properly (generally idle too high); "...DTC 411 indicates a dirty/ bad or connector issue w/daIdle Air Control valve (IAC). inspect it for crapola. Some can be cleaned. But our's shouldn't since the TSB says; "...Cleaning is not required on sludge tolerant throttle body designs released for 1991 and newer model years...." in Idle Air Control (IAC) Sludge; Poor Idle TSB 91-25-07 for 85-92 Bronco & F Series & many others; "...Hard cold starts, hesitation and stalls on initial start-up or during idle or decel may be caused by sludge in the throttle body and/or idle by-pass valve. Sludge deposits or oil film on the throttle body bore and plate or the idle air by-pass valve may cause one or more of the following conditions. Hard Cold Start, Stall On Initial Start-Up, Stall During Idle, Stall During Decel, Rough Idle, Rolling Idle, Hesitation During Acceleration. A new idle air by-pass service kit (F2PZ-9F939-A) is now available for service use to correct sludge contamination concerns of the throttle bore and plate only. It eliminates the need to clean the majority of past model throttle body applications. Cleaning is not required on sludge tolerant throttle body designs released for 1991 and newer model years..."
Source: by miesk5 at FSB
DTC 412 Cannot control RPM during KOER self-test high RPM check. \"...indicates that during the Engine Running Self-Test, engine rpm could not be controlled within the Self-Test upper limit band. Possible causes: Open or shorted circuit. Throttle linkage binding. Improper idle airflow set. Idle Air Control (IAC) solenoid contamination. Items external to Idle Air Control system that could affect engine rpm. Damaged IAC solenoid. Damaged Powertrain Control Module (PCM). Turn the key \"OFF\", connect a tachometer. Then start the engine and disconnect the Idle Air Control (IAC) harness connector. Does the rpm drop or engine stall? If it does, turn the key \"OFF\" and disconnect the IAC. With an Digital Volt/Ohm Meter (DVOM) check the resistance of the IAC solenoid. It should be between 6.0 and 13.0 ohms. Due to diode in the solenoid, place the DVOM (+) lead on the VPWR pin and the (-) lead on the IAC pin. If it is not within specification, replace the IAC solenoid...\" miesk5 Note; Ford says the range is 7-13 ohms
Source: by Vincent C at autorepair.about.com
DTC 41; "...KOEO; No HEGO sensor switching detected or disconnected. HEGO is bad, not connected, or missing. KOER; HEGO sensor indicates system lean. HEGO is going bad, missing." read more
Source: by miesk5 at FSB
DTC 42 "...HEGO is going bad, fuel pressure regulator is set too high, or exhaust leak..."
Source: by WestCoastFords.com via web.archive.org
DTC 42 O2 sensor voltage was stuck high for too long. (Rich).; "...Bad O2, or it's connector/wiring bad MAP sensor, Bad fuel pressure regulator, pull vac hose off, any gas in it or gas aroma means it's bad; Leaking injectors,restriction in fuel return line,or exhaust leak or clogged exhaust, lowering vacuum..." read more
Source: by miesk5 at FSB
DTC 44 Problems in the Thermactor Air Control system. Check vacuum lines, air pump, diverter valve, and solenoids.
Source: by miesk5 at FSB
DTC 44 (KOER) - Right Thermactor Inoperative - The thermactor system injects air into the exhaust ports in the heads downstream from the valves. Air is supplied from the smog pump through tubing and the TAD/TAB valves to a copper pipe between the heads on the firewall side of the engine, and ultimately to the exhaust passages. If your smog pump is disabled, or your disconnected the tubing or blocked the thermactor holes in the back of the heads, or if the TAD/TAB valves are bad, you will get these codes. My car has all of this stuff removed and used TFS Track Heat heads (with no thermactor provision), and naturally pulls these codes.
Source: by Matthew at corral.net
DTC 44 (KOER); Right Thermactor Inoperative; "...I had a similar issue that turned out to be the vacuum line to the Thermactor Air Bypass Valve. No CEL, just a code; 1. First check that the two vacuum lines are connected to the Vacuum Reservoir (coffee can) and the resevoir is in good repair with no leaks on the bottom. Frequently the can leaks or the vacuum lines are accidentally knocked off. Check the vacuum hose to the bottom of the Bypass Valve. Check the vacuum hose to the Diverter Valve. Check the vacuum hoses to the TAB/TAD Solenoids. Then check your TAB/TAD Solenoids. These are common easy to miss problems. Once these are ruled out all that is left is: Thermactor Air Supply Hoses. One-way Check Valves. Main TAB/TAD Valves..."
Source: by Seattle FSB (SeattleFSB) at FSB
DTC 44 (KOER); Right Thermactor Inoperative; "...indicates a Thermactor Air System leak which could be anywhere from the smog pump up front to include EGR solenoiids over on the right inside fender liner and all the way to the back of the engine which is what you see in the photos. There is also a smog tube that runs along the passenger side engine below the valve cover which runs to the back of the FI plenum up to a Air Bypass Valve (plastic) crossing over to the cross-over tube (exhaust) which is connected to that and the CAT, check valve and tube below. the Thermactor system is designed to capture spent gases and ultimatley send them down to the CAT to burn off etc. If you look closely you'll see the chek valve and CO tube is pipe threaded, use some anti-seize and don't over tighten and when putting the valve on the tube, you don't need a gasket for the CO tube ends but rather just use some bearing grease which melts and forms a nice gasket seal. this is a tip from Steve83; gaskets burn off and go away after a while and you're back with another vacuum leak etc..."
Source: by JKossarides ("The Bronco", Jean) at FSB
DTC 45/95 Thermactor air system inoperative-right side: "...The code 45/95 is an Air Management fault. These particular codes are used for the Thermactor Air Diverter (TAD)/Thermactor Air Bypass (TAB) valve system (Fig. 3). In following the diagnostic tree we were to first check for vacuum lines that could possibly be broken or disconnected. One line was found disconnected. One line was found disconnected. We also discovered that this particular vacuum line got its source vacuum at the same place the MAP sensor did. This leak, we believed, was the cause of the erratic readings that set the MAP sensor code 72. At this point the codes were cleared and the emissions were checked. The emissions were lower, but not good enough. And a code 95 was still present. We continued with the diagnostic tree and determined that the diverter valve was not at fault. We entered the output state check and cycled both the TAB and TAD solenoids on/off. They both worked correctly. Finally, we supplied vacuum to the solenoid to make sure that the vacuum did not leak down. The TAD solenoid would not hold vacuum. It slowly bled off. We replaced the solenoid. We then performed a KOEO and KOER test. No codes were present and emissions looked excellent. HCs were averaging about 97 to 112 ppm, and the CO was down around .2%. We concluded that the emissions readings were being affected by the vacuum bleeding off of the TAD solenoid. This allowed vacuum to be applied to the diverter valve at the TAD portion continuously. This resulted in the air always being diverted to the manifold before the oxygen sensor. The oxygen sensor would read lean, because of the extra oxygen, and therefore the computer would enrich the mixture. This is why the vehicle failed emissions..."
Source: by tomco-inc
DTC 452 Erratic Harsh Shift; PSOM Operates Correctly, OD light blinks in a 95; "...test the other sensor and it is way out of wack 1855Ohms. So this has to be the problem. Tomorrow I will replace it with a new one from the ford dealer..."
Source: by miesk5 and JRose 89 at Ford Bronco Zone Forums
DTC 452 Erratic Harsh Shift; Short Circuits, Common Locations TSB 95-02-11 on 94-95 Bronco & Trucks; SEE D: Code 452 - see Poss. Short Locations: 1. Driver's side A pillar trim screws may have been installed thru da 17K745 Sun Visor wire assy & .. bullet connector; 3. Scuff plate screws (driver's side) may pinch the 14A504 wire assy; 4 14401 wire assy may be trapped/pinched between Half car beam & instrument panel attachment (repeated as #7. the wire harness may be pinched/shorted behind the dash where the 14401 wire assy may come in contact w/a sharp edge on dash panel wall 5. shift cable assy near tranny may chaf the wire harness; the wire harness ; 7. repeated above..brake pedal-to-dash panel wall weld.
Source: by Ford via Chilton
DTC 46; "...Thermactor air unable to dump to atmosphere. Suspect diverter valve, solenoids, harness. Related Thermactor switch is bad or there is a vacuum leak in the line going to the valve closest from the smog pumps air output..."
Source: by miesk5 at FSB
DTC 51 - ECT sensor signal is greater than the Self-Test maximum of 4.6 volts...
Source: by miesk5 at Ford Bronco Zone Forums
DTC 511 (ROM failure) is quite rare. Usual causes for DTC 511; jump starting the vehicle, charging the battery w/ high output, pin point checks performed at the PCM and inadvertently grounding (shorting) a voltage sense line, and static electricity discharge. Be advised that ROM failure usually results in low EPC signal during light throttle cruise conditions
Source: by miesk5 at FSB
DTC 512 "...indicates the PCM has experienced a power interrupt in its Keep Alive Memory (KAM) circuit. If KAPWR is interrupted to the PCM, for example when installing a breakout box, or when battery is disconnected, DTC 512 may be stored in Continuous Memory. Key off. Disconnect Powertrain Control Module (PCM). Inspect for damaged or pushed out pins, corrosion, loose wires, etc. Service as necessary. Install breakout box, leave PCM disconnected. Measure voltage between Test Pin 1 and Test Pin 40 or 60 at the breakout box. While observing DVOM, grasp the EEC-IV harness and wiggle, shake or bend a small section while working from the PCM to the dash panel. Does DVOM indicate less than 10.5 volts? Make sure you have a good ground at G101 (Passenger side of engine compartment, near battery). If so I think I would go ahead and change the PCM as I do not know of any thing else out side the PCM to cause this...."
Source: by subford (Bill K) at fte
DTC 512 (M) Memory power (PCM pin 1) was interrupted; Was battery disconnected?
Source: by thorssell.net
DTC 522 & 654 indicate the gear selector was not in Park during Self-Test; "...Possible causes: Misadjusted linkage. Open or short in harness circuits. Damaged TR sensor. Damaged Powertrain Control Module (PCM) . OR CHECK THIS OUT, TECHNICAL BULLETIN # 230A, TRANSMISSION: E4OD SUBJECT: No upshift 4th gear starts, harsh upshifts, neutrals out after shifts APPLICATION: Ford-E/F Series, Bronco DATE: Jan 1995 NOTE: Click on image to make it larger. All of these concerns can be the result of an inappropriate Manual Lever Position (MLP) sensor signal. The MLP sensor consists of six resistors connected in series (ganged). The resistance of the MLP sensor will vary based on which range the transmission is in. The MLP circuit can be checked using the following steps. (Step 1) Check the MLPS ground: Turn the ignition on. The voltage on pin 46 (sensor ground ) should not exceed .1v. If the voltage is excessive, add an additional ground to the existing ground wire (figure 2). NOTE: Click on image to make it larger. Figure 2 Splice an additional ground from the existing ground wire to a known good ground.The negative post of the battery is the best. This view is of the pins of the MLP connector pins. NOTE: Click on image to make it larger. (Step 2) Check the MLPS voltage: The voltage at pin 30 should vary-in increments- according to the position of the manual lever (figure 3). MLP voltage (ignition on) should be within 20% of these specifications. Note It is recommended that you use a break-out box. If a break-out box is not available, you will need to pierce the wires to pins 30 and 46 for these tests. NOTE: Click on image to make it larger. (Step 3) Check the resistance of the MLPS: The resistance of the MLPS (pins 30 and 46) should change-in increments-with the position of the manual lever (figure 4). Note If this test is being done with a break-out box, disconnect the computer first (make sure the ignition is off). If this test is being done without a break-out box, disconnect the MLPS from the vehicle harness. Note Testing beyond this point will include tests of the harness. Consult the appropriate repair manual for this..."
Source: by fordbronco1995 ("JUICE") at FSB
DTC 53 (KOEO) TP sensor out of range TP sensor is stuck/sticking or just plain bad
Source: by miesk5 at Ford Bronco Zone Forums
DTC 536 - Brake On/Off circuit failure / switch not actuated during KOER test or shorted to ground
Source: by miesk5 at Ford Bronco Zone
DTC 536 - Brake On/Off circuit failure / switch not actuated during KOER test or shorted to ground
Source: by miesk5 at FSB
DTC 538 Insufficient RPM change during dynamic response test. "...This is another code generated when the dynamic response or "goose" test as some refer to it is not performed during the KOER test. The KOER test requires that after a certain length of time the throttle be opened to bring the idle above 2000 rpm for a short period of time. If the dynamic response test is not performed or the rpm's do not peak ABOVE 2000 rpm's this code will be generated. (Computer needs to compare changes in sensor readings at different RPM's to determine system operation and efficiency)..."
Source: by miesk5 at Ford Bronco Zone Forums
DTC 54 (orc*): ACT (Air Charge Temperature)/IAT (Intake Air Temperature) sensor voltage too high, indidcating -40degF. - suspect shorted sensor, harness
Source: by miesk5 at Ford Bronco Zone Forums
DTC 542 "...indicates that one of the following has occurred: No Start: Inertia Fuel Shutoff (IFS) switch not reset or electrically open (if in secondary circuit). Open circuit between the fuel pump and FPM circuit connection to the power-to-pump circuit. Poor fuel pump ground. Fuel pump electrically open..."
Source: by Ford via subford (Bill K) at fordf150.net
DTC 542 "...No Start: Inertia Fuel Shutoff (IFS) switch not reset or electrically open. Open circuit between the fuel pump and FPM circuit connection to the power-to-pump circuit. Poor fuel pump ground. Fuel pump electrically open. Engine Starts: Fuel pump secondary circuit short to power. Fuel pump relay contacts always closed. Open in FPM circuit between PCM and connection to the power-to-pump circuit. Left/front HO2S short to power (dual HO2S applications) Damaged Powertrain Control Module (PCM). Does the engine start? (For trucks with dual fuel tanks, verify tank selector is in the same position it was when KOEO DTC 542 was received.) Yes GO to J11. No GO to J15..."
Source: by SigEpBlue (Steve) at FSB
DTC 542 (KOEO & Memory code) Fuel pump circuit open; PCM to motor ground
Source: by Steve83 (Steve, That dirty old truck) at fordf150.net
DTC 542 (KOEO & Memory code) Fuel pump open, bad ground or always on
Source: by thorssell.net
DTC 542 (O,M) Fuel pump open, bad ground or always on; Check inertia fuel shutoff switch; behind passenger side kick panel. No Start: Inertia Fuel Shutoff (IFS) switch not reset or electrically open. Open circuit between the fuel pump and FPM circuit connection to the power-to-pump circuit. Poor fuel pump ground. Fuel pump electrically open. Engine Starts: Fuel pump secondary circuit short to power. Fuel pump relay contacts always closed. Open in FPM circuit between PCM and connection to the power-to-pump circuit. Left/front HO2S short to power (dual HO2S applications). Damaged Powertrain Control Module (PCM).
Source: by miesk5 at Ford Bronco Zone Forums
DTC 553 (O) Air management 2 circuit failure (AM1/TAD, AIRD) AIRD solenoid/circuit failure Testing
Source: by Ford via miesk5 at FSB
DTC 556 (O,M) Fuel pump relay primary circuit fault in a 90 4.9 F 150; "...You will need to trouble shoot the circuit to see if it is a EEC or FP relay, the inertia switch or corroded wiring, relay sockets, etc. The fuel pressure should be in the 45-60 psi range.Fuel Pressure Regulator (FPR) Delay TSB 93-22-14 for 90-93 4.9L (Cold Start & Idle Stall)..." READ MORE
Source: by miesk5 at Ford Bronco Zone Forums
DTC 56 (KOEO) TOT sensor output is greater than Self-Test maximum value of 4.8 volts.
Source: by miesk5 at Ford Bronco Zone Forums
DTC 565 Pin-Point Testing & Possible Causes
Source: by Ford via miesk5 at FSB
DTC 565 Pin-Point Testing & Possible Causes
Source: by Ford via miesk5 at Ford Bronco Zone Forums
DTC 61 - ECT sensor is less than the Self-Test minimum of 0.2 volt; indicates coolant temp greater than 250 deg F.
Source: by miesk5 at Ford Bronco Zone Forums
DTC 617 - 1-2 shift error. "...IF this code persists and you have noticed shift problems while driving, its going to be a shift servo inside the E4OD tha has failed. (Computer needs to control when the tranny is shifting)..."
Source: by greystreak92 (Joe B) at fte
DTC 62 E4OD 4/3 or 3/2 pressure switch circuit failed open
Source: by miesk5 at Ford Bronco Zone Forums
DTC 62, 628 and/or 1728 Transmission Shifts Hard TSB 98-4-19 in 90-96
Source: by Ford via miesk5 at FSB
DTC 622, Shift Solenoid 2: Improper gear selection depending on failure mode and manual lever position; refer to the Shift Solenoid Operation Chart. May flash transmission control indicator lamp. Diagnostic Trouble Codes: 617, 618, 619, 622, P0755, P0781, P0782, P0783, P0756. (Output circuit check, generated only by electrical conditions. May also be generated by other non-electronic related transmission hardware condition.)
Source: by Ford via miesk5 at FSB
DTC 624, 625, P1746, P1747 The Electronic Pressure Control solenoid is a variable force solenoid. The variable-force type solenoid is an electro-hydraulic actuator combining a solenoid and a regulating valve. It supplies electronic pressure control which regulates transmission line pressure and line modulator pressure. This is done by producing resisting forces to the main regulator and the line modulator circuits. These two pressures control clutch application pressures. Failed off — maximum electronic pressure control pressure, harsh engagements and shifts. May flash transmission control indicator lamp. CAUTION: The electronic pressure control pressure output from the variable force solenoid is NOT adjustable. Any modification to the electronic pressure control solenoid will affect the transmission warranty. (*Output circuit check, generated only by electrical condition.) Possible causes, Damaged harness connector. Damaged EPC solenoid. Damaged MLP sensor. Intermittent harness continuity. Damaged PCM connector pins. Pin Point testing; READ MUCH MORE
Source: by Ford via miesk5 at FSB
DTC 626, 628, 643, 652, P0741, P0743, P1754; "...Coast Clutch Solenoid (CCS) 7M107; The Coast Clutch Solenoid provides coast clutch control by shifting the coast clutch shift valve. The solenoid is activated by pressing the transmission control switch or by selecting the 1 or 2 range with the transmission gearshift selector lever. In manual 1 and 2, the coast clutch is controlled by the solenoid and also hydraulically as a fail-safe to ensure engine braking. In reverse, the coast clutch is controlled hydraulically and the solenoid is not on. NOTE: On certain applications, the coast clutch is controlled by the PCM in the overdrive position (TCS OFF) in gears 1, 2, and 3. Symptoms: Failed on â Third gear engine braking with (D) range selected. Failed off â No third gear engine braking in overdrive cancel..."
Source: by Ford via Steve83 (Steve, That dirty old truck) at SuperMotors.net
DTC 628; "...code 628 can be caused by a mechanical problem or electrical problem. First thing to do is to check power to the solenoid connector at the transmission. These solenoids are 12 volt solenoids, not 5 volts......I have attached a few pictures for reference. Unplug the transmission connector and check the VPWR wire for 12 volts first with the key on at the harness itself. Then if OK, check the solenoid resistance with an OHM meter on the 200 OHM scale through the pin on the connector coming out of the transmission marked TCC & VPWR pins. Should be 0.98 to 1.6 OHMS as MTB has said. I usually used a special transmission tester tool, but this is the only way you can do it. I have seen many of these code 628 in the past, and I'm sorry to say 95% have been internal Mechanical failure. These tests for the solenoids are only going to tell you if the solenoid is open or within spec. It will not tell you if a piece of junk is stuck in the solenoid causing it to bleed pressure to the TCC, therefore giving you a rough running engine, shuddering feeling or stall in 2nd, 3rd, or 4th gear caused by the Torque converter clutch being applied at the wrong time..."
Source: by Fordace at lincolnsonline.com
DTC 628; "...I did things in a stupid-simple way when the 628 came up: I tapped into the TCC line, and attached a voltmeter between that line and chassis ground. While driving, I could watch for it to go between zero volts (meaning the PCM was commanding the converter to lock) and battery voltage (meaning the converter should be unlocked). It sounds counterintuitive at first, but that's a matter of perspective, I suppose. Anyhow, if you see the PCM trying to lock the TCC and nothing happens to the engine speed, or if you can give it a little more throttle and the engine speed rises while it's commanded to lock, then you're assured a problem exists. If there was an electrical problem, then the PCM should also be giving you a code 627 as well. The 628 indicates excessive converter slippage. At a steady cruise, say your 60 mph, if you tap the brake the engine speed should rise slightly, and then come back down as the TCC re-engages. This condition can be intermittent, and it's more of a mechanical problem than an electrical one. The fix for a slipping TCC is to replace the torque converter and stator shaft seal, nothing more. You'd be out a little over a hundred bucks probably, and a few hours' labor, if you get one through a reputable transmission shop. I wouldn't buy anything but an OE-type replacement. You may even be able to get a Motorcraft/Ford replacement through a local dealership, but I've no clue how much their price would be..."
Source: by SigEpBlue (Steve) at FSB
DTC 629,* P0741,** P0743,** P1743, P1742, P1744. "...(*Output circuit check, generated only by electrical condition. **May also be generated by other non-electronic related transmission hardware condition.) Symptoms: Failed on — engine stalls in drive at idle low speeds with brake applied or manual 2. Failed off — converter clutch never engages. May flash transmission control indicator lamp. Torque converter clutch solenoid provides torque converter clutch control by shifting the converter clutch control valve to apply or release the torque converter clutch..." from 1996 All F-Series and Bronco with E4OD Automatic Transmission Workshop Manual
Source: by Ford via thedieselstop.com
DTC 63 Throttle Position Sensor (TPS) voltage too low. Suspect open TP sensor, harness
Source: by miesk5 at FSB
DTC 632 - O/D Cancel switch, Overdrive cancel switch did not change state during KOER; is possibly the result of the test being done incorrectly. When you do a KOER test, you need to do a Dynamic Response Check is used to verify operation of the Throttle Position Sensor (TPS), Mass Air Flow (MAF), Manifold Absolute Pressure(MAP), and Knock Sensor (KS) during a brief wide open throttle condition. The famed "Goose test".
Source: by Vincent C at autorepair.about.com
DTC 632 - OD cancel switch not changing state. "...During the KOER test, AFTER the initial recognition code is generated, the brake pedal must be applied, the OD switch must be turned off and then back on and finally the "goose" test must be performed. This code is generated when the person performing the KOER test fails to deactivate and reactivate the OD cancel switch at the end of the shift lever. It does NOT indicate a problem unless the switch WAS INDEED deactivated and reactivated and the code still came up. (Computer needs to know if the tranny is in OD or not)..."
Source: by greystreak92 (Joe B) at fte
DTC 634; "...Hard 1-2 shift after she warms up...1-2 accumulator problem. Also the line modulator valve can cause intermittent harsh shifts, but generally it would happen on more than one gear change..."
Source: by Baumann Electronic Controls, LLC becontrols.com
DTC 636 Transmission Fluid Temp (TFT) higher or lower than expected; "...Can be caused by a bad connector or harness (an open circuit, or short to Ground / Batt), or the transmission was overheated. Once you remove the pan locate the sensor in the valve body and remove the electrical connector very carefully. The sensor is about the size of a pen cap. To remove the sensor carefully unlock the stop tab and twist it, pull down to remove it. It comes out before a full quarter turn is made. Put it back in the reverse order. When you get the sensor to come out be prepared to catch the trans fluid that follows behind it, you will get less than a quart out of it. It is located in da Pack between Converter Clutch Control (CCC) Solenoid & the Coast Clutch Solenoid. try the connections first. They are usually the root of the problem..."
Source: by miesk5 at FSB
DTC 636 Transmission Fluid Temp (TFT) higher or lower than expected; "...Can be caused by a bad connector or harness (an open circuit, or short to Ground / Batt), or the transmission was overheated. Once you remove the pan locate the sensor in the valve body and remove the electrical connector very carefully. The sensor is about the size of a pen cap. To remove the sensor carefully unlock the stop tab and twist it, pull down to remove it. It comes out before a full quarter turn is made. Put it back in the reverse order. When you get the sensor to come out be prepared to catch the trans fluid that follows behind it, you will get less than a quart out of it. It is located in da Pack between Converter Clutch Control (CCC) Solenoid & the Coast Clutch Solenoid. try the connections first. They are usually the root of the problem..."
Source: by miesk5 at Ford Bronco Zone
DTC 636 Transmission Fluid Temp (TFT) higher or lower than expected; "...The DTC 636 is the only one I'd be worried about at this point. You probably smoked the torque converter clutch running..."
Source: by SigEpBlue (Steve) at FSB
DTC 636, P1711 TFT Sensor Out of On-Board Diagnostics Range; 637, 638, P0712, P0713 TFT Sensor Circuit Open/Grounded; 657, P1783 Transmission Overtemp Indicated (149°C [300°F]); Transmission Oil Temperature Sensor (TOT) Pinpoint Test & Connector Pin-Out Diagram from 1996 All F-Series and Bronco with E4OD Automatic Transmission Workshop Manual
Source: by Ford via thedieselstop.com
DTC 637 - TOT sensor circuit above maximum voltage possible causes: Damaged TOT sensor. Open harness circuit(s). Damaged processor. or the transmission was overheated. The transmission fluid temperature sensor is located on the solenoid body assembly in the transmission sump. It is a temperature-sensitive device called a thermistor. The resistance value of the transmission fluid temperature sensor will vary with temperature change. The powertrain control module monitors voltage across the transmission fluid temperature sensor to determine the temperature of the transmission fluid. The powertrain control module uses this signal to determine whether a cold start shift schedule is necessary. The cold start shift schedule lowers shift speeds to allow for the reduced performance of cold engine operation. The powertrain control module also uses the transmission fluid temperature sensor input to adjust electronic pressure control pressure for temperature effects and inhibit torque converter clutch operation during the warm-up period. Symptoms: Torque converter clutch and stabilized shift schedule happens too soon after a cold start. Codes P1783 or 657 indicate transmission fluid temperature exceeds 132°C (270° F), results in increased EPC pressure and torque converter clutch engagement. May flash transmission control indicator lamp. Diagnostic Trouble Codes: 636, 637, 638, 657, P0712, P0713, P1711, P1783.
Source: by Ford via miesk5 at FSB
DTC 64 Intake Air Temp (IAT)/ (Air Charge Temperature (ACT) prior to 1992); sensor out of range (signal voltage too low), sensor is bad/dirty or wiring is grounded
Source: by miesk5 at FSB
DTC 67 & 634 indicate the MLP sensor is out of Self-Test range when the gear selector is in PARK; "...Possible causes: Misadjusted linkage. Open or short in harness circuits. Damaged MLP sensor. Damaged PCM. miesk5 NOTE;... for Escort/Tracer tranny MLPS etc.; but the Bronco troubleshooting process will be similar exc for connector pins, etc. read more on testing
Source: by Ford via thedieselstop.com
DTC 67 & DTC 634; E4OD Nagging Neutral Nonsense & Pinpoint Test, Manual Lever Position (MLPS) also called Transmission Range (TR) Sensor. "...One of the most-difficult problems to diagnose on a Ford car or truck is a sudden neutral condition while the vehicle is cruising in 4th gear. Now this can have a number of causes, depending on which transmission is in the car or truck, but the cause we are going to discuss here is that #(~! *&A% Manual Lever Position Sensor – that’s right, the old MLPS. This sensor is responsible for more malfunctions than any other sensor in the system, and the kicker is that it seldom stores a code 67 or 634. Actually there is a standing joke in our industry that says, “You got a problem with a Ford, change the MLPS; it fixes everything,” which ain’t that funny because it’s not that far from the truth. Some of the problems the MLPS can cause are wrong gear starts, TCC hunting, no 4th gear, engine stalling, high or erratic line pressure and the problem that this article is about – a sudden neutral condition. Whether the MLPS is attached to an E4OD, AXODE, AODE or CD4E, the operating characteristics are the same. What that means is the MLPS is classified as a step-down resistor. The MLPS is supplied 5 volts from the computer as a reference voltage, and as the shift lever is moved from park toward manual low, the voltage in each gear-shift position will decrease as shown in Figure 1. The MLPS also can be checked for correct resistance, also shown in Figure 1. This way, if the resistance checked good on the bench but the voltage does not check good in the vehicle, you know there must be a wiring or ground problem. I know what you are thinking: You replace the MLPS on every job you do, so why should you check the resistance on a new part? Well, that’s fine, but one thing has become very clear lately: NEW DOES NOT MEAN GOOD! Now, let’s get to the meat of the problem. As you can see in Figure 1, the voltage in the drive/overdrive position can be 1.88 to 2.30 volts. The O.D. Cancel button, on those vehicles equipped with one, has no effect on the voltage seen in the drive position, nor does it matter whether the vehicle has a gas or diesel engine. This would be the voltage seen in the D or D position if it were available on the scan-tool screen in the data mode. Unfortunately, this information is not always available, and this “glitch” may occur faster than the scan-tool’s update capability so the voltage jump would be missed. Therefore, a digital multimeter must be used to monitor this voltage. This is of the utmost importance in diagnosing the sudden-neutral condition. This voltage should be monitored when the neutral condition occurs by placing the multimeter’s positive lead to computer terminal 30 if it is an EEC-IV system, as illustrated in Figure 2, or to terminal 64 if it is an EEC-V system. This wire is light blue/yellow on all applications except vehicles with the CD4E. On these the signal wire is red/black. Now, here is where this gets a little involved. The negative lead of the multimeter should be placed at the MLPS signal-return ground terminal at the MLPS. The reason is that the ground circuit for the MLPS can be shared by as many as FIVE other sensors, as seen in the wiring diagram in Figure 2. This means that there are factory splices in this ground circuit. If you check this ground at computer terminal 46 for the EEC- IV or computer terminal 91 for the EEC-V, the ground may check good but could be bad at the MLPS if there is a problem on the MLPS side of the splice, as also can be seen in the wiring diagram in Figure 2. The ground-circuit wire for 1989-90 F- and E-series trucks is black/white; all other vehicles use a gray/red ground wire except for CD4E applications, on which the ground wire is black/blue. Once the multimeter is connected to these circuits, as seen in Figure 3, place the meter where it can be seen while driving. When the transmission suddenly neutrals, be sure to have someone observe the multimeter, or use the meter’s MIN/MAX feature to record the highest and lowest voltage readings that occurred in the circuit. If the voltage jumps toward 3 volts as shown in Figure 3, and at that very moment the transmission neutrals, either the MLPS is faulty or the MLPS ground circuit is poor. Under normal conditions, this voltage reading SHOULD NOT CHANGE! When the voltage jumps toward 3 volts, this indicates a neutral-shift- lever position to the processor. This confuses the computer’s logic system, and therefore the computer is unable to fire the shift solenoids correctly (I think), and – BAM – you have a sudden-neutral condition. Why does the voltage jump because of a poor ground? The poorer the ground, the higher the resistance will be in that ground circuit. The higher resistance will cause the voltage in the overdrive or drive position to rise toward the 5-volt reference voltage, much like putting a bend in a garden hose would raise the pressure in the hose behind the bend. Ground- circuit integrity can be verified by placing the positive multimeter lead to the MLPS ground terminal at the MLPS and the negative multimeter lead to the negative battery post, as seen in Figure 4. With the multimeter set to DC volts and the engine running, the maximum voltage should be 0.1 volt. If more than 0.1 volt is seen on this ground circuit, it is NOT a good ground. In order to correct this condition, cut the ground wire close to the MLPS, attach it to a known good ground and recheck as previously described. Two things must be remembered here. One is that the return electricity will seek the path of least resistance. This path MUST be the ground circuit, NOT your multimeter. That’s why you should see a maximum of 0.1 volt on any 5-volt-reference ground circuit; 0.3 is acceptable on a 12-volt-reference voltage supply. The second thing to remember is that most electrical- fault phone calls I receive on the ATSG helpline are ground-related problems, so be sure to use the voltage-drop method of checking grounds as described. It may help to prevent you from falling into this trap..." See Diagrams & instructions
Source: by Pete L at transonline.com
DTC 67 & DTC 634; Manual Lever Position/Transmission Range (MLP/TR) Sensor Pin-Point Test in 92-96; from Ford EVTM; "...Check the resistance of the MLPS: The resistance of the MLPS (pins 30 and 46).." read more
Source: by Ford via alldata & justanswer.com
DTC 67 Neutral Drive Switch (NDS) Circuit Open; "...In some cases all of us at one time or another have had to "jiggle' the column shifter to get the vehicle to start because over time things losen up from DD useage.....in the Haynes Manual transmission section and www.broncolinks.com there's a diagram referring to "Point A" which is the column shift linkage and the transmission tab. A sure way to correct the "jiggling" is to go underneath the BKO on the drivers side and LOSEN the "nut" on column shift linkage and tranny tab JUST ENOUGH to click the tranny tab all the way back until it stops then 2 clicks forward and tighten the "nut".....now the column shift linkage and transmission are in sync when you go thru the grears, assuming the steering column is in resonable condition this should help correct that problem.......TOO MANY TIMES THE NSS IS DEEMED THE CULPRIT for none start when it isn't so this is a simple check to make sure. There is also another PRNDDL adjustment, but you need to remove the black plastic collar on the steering wheel, this is usually done when an actuator breaks and using pliers drive the rod downward with key on to start.....there is usually a white cable that wraps around and attached to a small mm screw IIRC that when lossened a bit it allows you to adjust the "needle" that registers on each letter of the PRNDDL..be careful because it's attached with a very fine wire loop and easily broken. The "upper ignition actuator" is another culprit because they're made of cheap pot metal.....and a PITA job to do..."
Source: by JKossarides at FSB
DTC 67 Neutral Drive Switch (NDS) Circuit Open; "...This probably is indicating that the neutral drive safety switch is faulty and needs replaced. The purpose of the switch is to prevent activation of the starter (by creating an open circuit) when the transmission is in any gear other than P (park) or N (neutral)..."
Source: by bluelightnin6 at 2carpros.com
DTC 67 Park/Neutral Position (PNP) switch circuit open - A/C on during Self-Test
Source: by freeautomechanic.com
DTC 67; "..One poss is that the NSS (or also called the MLPS) was ok...or connector was/is bad/corroded; or AC was left on, or transmission was in gear during the Self Test..." read more
Source: by miesk5 at fordfzone.com
DTC 77 system failed to recognise brief WOT dynamic resistance test. Need to press gas pedal during KOER; Operator didn't execute WOT when told to during self test.
Source: by miesk5 at FSB
DTC 84 EGR Vacuum Regulator (EVR); also called EGR Vacuum Solenoid failed; Bad or unplugged EGR solenoid,or circuit is bad
Source: by miesk5 at FSB
DTC 84/558: CHECK RESISTANCE OF EVR SOLENOID indicates a failure in the EGR Vacuum Regulator (EVR) solenoid circuit/Damaged EVR solenoid; Open harness, Shorted harness, Damaged Powertrain Control Module (PCM). Key off. Disconnect EVR solenoid. Measure solenoid resistance. Resistance Specification, 7.5L 100 to 135 ohms, All Others 20 to 70 ohms. Is resistance within specification ? Yes - GO to DN11,. No - REPLACE EVR solenoid assembly. RERUN Quick Test. DN11 CHECK VPWR CIRCUIT VOLTAGE, Key on, engine off. EVR solenoid disconnected. Measure voltage between battery negative post and VPWR circuit at the EVR solenoid vehicle harness connector. Is voltage greater than 10.5 volts? No - SERVICE open circuit. RECONNECT EVR solenoid.RERUN Quick Test. DN12 CHECK EVR CIRCUIT CONTINUITY, Key off. EVR solenoid disconnected. Disconnect PCM. Inspect for damaged or pushed out pins, corrosion, loose wires, etc. Service as necessary. Install breakout box, leave PCM disconnected. Measure resistance between Test Pin 33 at the breakout box and EVR circuit at the EVR solenoid vehicle harness connector. Is resistance less than 5.0 ohms? No - SERVICE open circuit. REMOVE breakout box. RECONNECT all components.RERUN Quick Test. Yes - GO to DN13. DN13 CHECK EVR CIRCUIT FOR SHORT TO POWER OR GROUND. Key off. EVR solenoid disconnected. Breakout box installed, PCM disconnected. Measure resistance between Test Pin 33 and Test Pins 37 and 57 at the breakout box. Measure resistance between Test Pin 33 and Test Pin 40, 46 and 60 at the breakout box. Is each resistance greater than 10,000 ohms? No - SERVICE short circuit. REMOVE breakout box. RECONNECT all components. RERUN Quick Test. If DTC is repeated, REPLACE EVR solenoid. Yes -REPLACE PCM. REMOVE breakout box. RECONNECT EVR solenoid. RERUN Quick Test.."
Source: by Ford via miesk5 at FSB
DTC 85 Canister purge solenoid circuit failure; CANP solenoid is bad or circuit is bad.; "...Ck vacuum line between the passenger side of da engine and the vapor canister on frame rail; could have hit the exhaust manifold..." READ MORE
Source: by miesk5 at Ford Bronco Zone Forums
DTC 87 - Fuel Pump Relay Circuit Failure: "...suspect inertia switch, fusible link, FP relay..."
Source: by miesk5 at Ford Bronco Zone Forums
DTC 87, 95 & 96; "...These codes relate to low or no power reaching the fuel pump. Start testing at the fuel pump relay. The relay must respond to the EEC processor and the relay contacts must be a low resistance path for fuel pump power. Relay testing can be done in a couple minutes with the fuel pump test table. Fuel pump relay testing;1. Use solenoid test at EEC pin 22 to check relay coil current draw. 2. Voltage at pump power terminal must be within .5v of battery power when relay is turned on with amp meter at pin 22. Check power from battery if voltage is low. Check the inertia switch and fuse if battery voltage is missing. Pin 22- (light blue-orange) Grounded to turn "on". Voltage will drop to about 1v when "on". Current draw will be 160 to 270mA Pin 8- fuel pump monitor (dark green-yellow) 0v engine off, battery voltage with engine running..."
Source: by Dustin S (Dustball, Mellow Yellow, Mr. Laser Boy) at FSB
DTC 91 & 92 in E4OD; "...1-2 Shift solenoid circuit failure; 93 Coast clutch solenoid circuit failure(e4od), 94 Converter clutch solenoid circuit failure, 99 Electronic pressure control circuit failure, and another with two descriptions. 56 TOT reads & minus 40deg. F or circuit open and 56 Vaf or MAF circuit amove maxium voltage; I'd try pulling & cleaning the shift solenoid pack connector, and then inspect the lines from the PCM to that connector for shorts and opens. All of those codes are pointing to a problem with the connections to the solenoid pack, in the harness, or in the solenoid pack itself. I wouldn't keep driving it like you are, though. The 'default' gear is 4th, so you're creating a lot of heat trying to get going..."
Source: by SigEpBlue (Steve) at FSB
DTC 95 - bad ground or always on. Possible bad fuel pump ground or open between fuel pump and pin 8 at PCM
Source: by miesk5 at Ford Bronco Zone Forums
DTC 96 Fuel Pump circuit failure, battery to processor; "check batty cables, connectors, grounds for corrosion; check voltage @ pump, etc..."
Source: by miesk5 at Ford Bronco Zone Forums
DTC 98 Hard fault present; "...Failure Mode Effects Management (FMEM) FMEM is an alternate system strategy in the PCM designed to maintain vehicle operation should one or more sensor inputs fail. When a sensor input is perceived to be out-of-limits by the PCM, an alternative strategy will be initiated. The PCM will substitute a fixed in-limit sensor value and will continue to monitor the faulty sensor input. If the faulty sensor operates within limits, the PCM will return to the normal engine running strategy. Engine Running DTC 98 or 998 will be displayed when FMEM is in effect. The Malfunction Indicator Lamp (MIL)/Message will remain on when FMEM is in effect. The MIL will come on while the engine is operating in Failure Mode Effects Management (FMEM) or Hardware Limited Operation Strategy (HLOS) modes. The light will stay on for at least 10 seconds, then stay on as long as the fault causing it is present. If the MIL flashes quickly (less than 10 seconds), the MIL circuit should be checked for concerns. Refer to «Quick Test». In FMEM mode, the PCM is receiving a sensor signal that is outside the limits set by the calibration strategy. In this mode, the PCM uses an alternate engine control strategy to maintain reasonable vehicle operation in spite of the fault. The DTC associated with this fault is stored in Keep Alive Memory (KAM). If the fault is no longer present, the light will turn off and the vehicle will return to the normal vehicle strategy. The DTC stored when the light was on is kept in Continuous Memory for the next 80 warm-up cycles (40 cycles on some applications) and then erased. This Continuous Memory DTC can be accessed by running the Key On Engine Off Self-Test..."
Source: by miesk5 at Ford Bronco Zone Forums
DTC 99 Transmission Control Indicator Lamp; "...That would probably be an EPC circuit failure. If this circuit fails line pressure should go to full at all times. The full line pressure puts a good deal of extra load on the engine, and will usually effect the idle. It is especially noticeable if your engine is already in need of a tuneup. You will need to check the electronic pressure control solenoid and its wiring. Either of these could be causing the EPC code..."
Source: by Baumann Electronic Controls, LLC becontrols.com
DTC P0171, P0172, P0174 & P0175, P1130, P1131, P1132, P1150, P1151, P1152; 181, 189 (Fuel system lean, Bank 1 or 2), 179, 188 (Fuel system rich, Bank 1 or 2); 171, 172, 173 (HO2S11 lack of switching, Bank 1); 175, 176, 177 (HO2S21 lack of switching, Bank 2); 184, 185 (MAF higher/lower than expected); 186, 187 (Injector pulse width higher/lower than expected) & Possible Causes in MAF Contamination TSB 98-23-10 for 94-96; NOTE: THE FOLLOWING PROCEDURE MAY ALSO BE USED TO DIAGNOSE VEHICLES THAT DO NOT HAVE FUEL SYSTEM/HO2S SENSOR DTCs. Symptoms: Lack of Power, Spark Knock/Detonation, Buck/Jerk Hesitation/Surge on Acceleration
Source: by Ford via miesk5 at FSB
DTCs 2 & 3 digits & some Possible Causes, MANY CODES!
Source: by freeautomechanic.com
DTCs 2 & 3 digits & some Possible Causes, MANY CODES!
Source: by minivanmadness via replay.web.archive.org/
DTCs 2 digits
Source: by Ryan M (Fireguy50) at fordfuelinjection.com
DTCs 2 digits & some Possible Causes
Source: by mustangpartstech.com
DTCs 2 digits & some Possible Causes, MANY CODES!
Source: by Tomco Inc. tomco-inc.com
DTCs 2 digits & some Possible Causes, MANY CODES!
Source: by minivanmadness via replay.web.archive.org
DTCs 2 digits & some Possible Causes; MANY CODES!
Source: by WestCoastFords.com via web.archive.org
DTCs 2 digits & some Possible Causes; MANY CODES!
Source: by Geargambler at svtsnake.com
DTCs 2 digits & some Possible Causes; MANY CODES!
Source: by whateverittakesracing.com
DTCs 2 digits & some Possible Causes; MANY CODES!; "... Fix any codes from the KOEO test before you do the running test (KOER, key on, engine running)..."
Source: by massdriven.com
DTCs 2 digits & some Possible Causes; SOME CODES! (under license from Delmar Publishers, comb of Chilton/Nichols/Delmar & Haynes); some may be incorrect, as reported by Seabronc, thanks Seabronc! NEW SITE URL!!! MUST REGISTER TO VIEW; select year, make, model, engine size and go to appropriate section
Source: by Chilton via AutoZone
DTCs 3 Digits
Source: by Ryan M (Fireguy50) at fordfuelinjection.com
DTCs 3 digits
Source: by Steve83 (Steve, That dirty old truck) at fordf150.net
DTCs 3 digits
Source: by Geargambler at svtsnake.com
DTCs 3 digits
Source: by whateverittakesracing.com
DTCs 3 digits & OBD II & Possible Causes & Repair Procedures for E4OD from 1996 All F-Series and Bronco with E4OD Automatic Transmission Workshop Manual
Source: by ford via thedieselstop.com
DTCs 3 digits & some Possible Causes - MOSTLY FOR DIESELS, MANY CODES!
Source: by Ford via thedieselstop.com
DTCs 3 digits & some Possible Causes, MANY CODES!
Source: by muscularmustangs.com
DTCs 3 digits & some Possible Causes, MANY CODES!
Source: by minivanmadness via replay.web.archive.org
DTCs 3 digits & some Possible Causes; MANY CODES (for Aussie Fords, but similar)
Source: by fordmods.com
DTCs 3 digits & some Possible Causes; MANY CODES!
Source: by thorssell.net
DTCs 3 digits & some Possible Causes; MANY CODES!
Source: by slingblade at The National Lightning Owners Club
E4OD Controls Overview, Sensors, DTC (s) & Diagram; Powertrain Control Module (PCM) 12A650: On vehicles equipped with gasoline engines, the operation of the E4OD automatic transmission is controlled by the powertrain control module. Many input sensors provide information to the powertrain control module, which then controls the actuators that affect transmission operation..." READ MUCH MORE
Source: by Ford via Steve83 (Steve, That dirty old truck) at SuperMotors.net
E4OD Limp Mode; "...If all the shifts are hard, the computer is going into limp mode which causes the trans to shift hard because the pressures are increased.The computer goes into limp mode when it senses an error in the transmission shifting or electrical system.The most common cause for this is the transmission range sensor.This is the sensor that is bolted to the drivers side of the transmission case with the shift lever arm going through the center of the sensor.Try disconnecting the battery for 15 minutes with the headlamps on.This should clear the limp mode and return the transmission to normal shift strategy. If it does then the problem is intermittent.If it still shifts hard then the fault is continuously occurring.It is possible that there is another input/output signal problem, but 99% of the time it is the range sensor especially if it clears limp mode proving the problem is intermittent..."
Source: by Kenny Z at justanswer.com
E4OD to C6 EEC Swap Info; "..."...I can make the electrical work Just the cost of the computer, $50-$200 depending on your shoping skills. 1994-95 5.0L Mustang (manual trans) F4ZF-12A650-EA T4M0, A1 CARDONE Part # 785918 ,STANDARD MOTOR PRODUCTS Part # EM10101..."
Source: by Ryan M (Fireguy50) at FSB
EEC for MAF conversion pics & part number in a 95 351W
Source: by Frank C (NDIXIE, AKMUD) at SuperMotors.net
EEC III Testing, Pin-Out, Wiring & Vacuum Diagrams in an 82; "...Woe was me, when I found out my 82 Ford Bronco was an EEC 3; had searched all over the engine compartment for the infamous "self test connector", only to find NONE..."
Source: by Tommy at home.comcast.net/~TommySpace/EEC3.html
EEC Info for EFI Swap for 302EFI to 351
Source: by urban_cowboy at FSB
EEC Installation for an EFI Swap in an 83 4.9 (also, scroll to many sub-topics on his swap)
Source: by Michael C (collinsperformance, The Money Monster) at SuperMotors.net
EEC IV "...was introduced in 1983 and has gone through several major physical changes, with the earliest models showing a fairly simple two board design using through hole soldered components. The last of the EEC-IV designs were much more current in technology, showing extensive use of surface mount components and a much more finished and complex appearance. In between, there appears to be a variety of mother/daughter board and other designs. Still, they are all called EEC-IV, although somewhere in its life there was a Ford P/N generational change..."
Source: by auto-diagnostics.info
EEC IV 5.0L 49 State & High Altitude Calibration Conversion (EEC IV Processor Change) TSB 92-16-9 for 92 Bronco, Econoline, F 150 & F 250
Source: by Ford via Chilton
EEC IV Pin-Outs (Partial) in 88-89 & 90-91 Bronco 4.9; 88-90, 91 & 92-93 Bronco 5.0; 88-91 & 92-93 Bronco 5.8; Looking Into Harness Connectors in Ford Electronic Engine Control Overview, Chapter 12, of Ford Fuel Injection and Electronic Engine Control: How to Understand, Service and Modify, 1988-1993
Source: by Charles O. Probst via yunost.ru
EEC IV Pin-Outs (Partial) Wiring Diagram in an 84
Source: by toddcomputer.com
EEC IV Replacement Cost in a 94 F 150; "...225 for PCM/ECU/EEC/whatever from a boneyard that they like to use; 1.3 hrs @ $95/hr for diagnostics = $123.50 1.5 hrs @ $95/hr for R&R = $142.50; $39.00 for "shop supplies".
Source: by wjr at fourdoorbronco.com
EEC IV Self Test Connector pic in a 95 (near driver's side hood hinge)
Source: by s8c2 (the wagon) at SuperMotors.net
EEC IV Strategies
Source: by Ford via miesk5 at broncolinks.com/gallery
EEC IV System Has NO Control Over the Following Items; "...Fuel quantity and quality; Damaged or faulty ignition components; Internal Engine Condition - rings, valves, Timing belt, etc.; Starter & Battery circuit; Dual Hall sensor; TFI or DIS module; Distributor condition or function; Camshaft sensor; Crankshaft sensor; Ignition or DIS coil; Engine governor module..."
Source: by Ford via arrc.epnet.com
EEC Processor, MIL On with DTC 173 in Continuous Memory w/Pass Code 111 in KOEO & KOER, Replace EEC TSB 92-18-12 for 91-92 5.8L Bronco, Econoline & F Series
Source: by Ford via Chilton
EEC Selection for Speed Density to Mass Air Conversion & Parts List with Cost. F150, Bronco, Mustang, Part 1
Source: by C. Asaravala at fordmuscle.com
EEC Selection Info for Speed Density to Mass Air Conversion & Parts List in an 89 F250 5.8 Manual Transmission
Source: by itsacrazyasian at FSB
EEC Selection Info for Speed Density to Mass Air Conversion & Parts List with Cost in a 93 F150, 5.0, E4OD; "...For this article, I will be doing a 93 Ford F-150, 5.0, E4OD trans. Because they don't make a kit for this, I will be re-wiring the harness, and using a PCM and MAF out of a 95 f-150, 5.0, E4OD. If you have a truck with a non-electronic Trans, like the old AOD's, or C-6's, etc, you can use a MAF conversion kit..." Read More
Source: by Mike C at eecperformance.com
EEC Selection Info for Speed Density to Mass Air Conversion & Parts List, Bronco, F 150
Source: by OX1 (OX, James O) at off-road.com
EEC Selection Info for Speed Density to Mass Air Conversion for Bronco & F 150; "...To convert SD trucks with E4OD/AODE transmissions to MAF, some people use the CA 5.8 MAF/E4OD (F5TF-12A650-BYA). Mike Wesley says he uses the F5TF-12A650-HB (95 CA 5.0 MAF/E4OD) on a 750+ HP daily driver 415 stroker Lightning with a Vortech S trim. It runs open loop, has been reprogrammed, drives like stock, gets 17 MPG and will run low 10’s at 130+ in the 1/4 mile and A/C and cruise work great. Both of these EEC’s are set to use 4.10 gears. If a smaller ratio is used, say 3.55, you could use the F5TF-12A650-GB. There are probably 15-20 EEC’s available to convert a SD (later model) to MAF (some of these may compromise the ability to stay emissions legal). If you have an early SD truck with AOD, re-wire to the Mustang EEC (Ford MotorSport sells this kit). You’ll have to move/add quite a few wires, and you might not like the results if you’re not able to re-calibrate the EEC (like the Pro-M ’low cost’ kit, Kenne Bell, LCA and Downs Ford come pre-re-calibrated). The engine shuts down at 85 MPH, shifting is fairly sloppy and too early (at least on a Lightning). All Ford EECs shift poorly -- except for the Lightning, which is only slightly firmer. To use the Mustang EEC on a truck with an E4OD/AODE, you would need to run two EECs in parallel. The Mustang EEC runs the engine, the existing truck EEC controls the trans. Pro-M sells a kit like this..." READ MUCH MORE
Source: by Tom C via Ryan M (Fireguy50) at fordfuelinjection.com
EEC Selection Info for Speed Density to Mass Air Conversion for EFI in a 393 91
Source: by Tiffany M (tmwalmart) at FSB
EEC Selection; 302 to 351 EFI Swap Tips
Source: by Ryan M (Fireguy50) at FSB
EEC Strategies "...Start / Crank, Cold Start & Warm Up, Cold Drive-Away, Warm Idle, Warm Cruise, Full-Throttle Acceleration, Deceleration; Failure Mode & Adaptive Strategy
Source: by Ryan M (Fireguy50) at fordfuelinjection.com
EFI Swap Using a “High-Output” Engine PCM with a non-HO Engine Camshaft; "...If you leave the injectors in the HO order you might notice a slight effect on idle quality..."
Source: by Ryan M (Fireguy50) at fordfuelinjection.com
Electrical and Vacuum Troubleshooting Manual (EVTM) for an 86 (Partial); Speed Control on pages 135-139, A/C & Heater on pages 140-145, Radio on pages 127-129
Source: by Chris B (Blue, bronco boy) at telus.net
Engine Compartment Relay Mounting Bracket Fabrication
Source: by Seattle FSB (SeattleFSB) at FSB
Engine Compartment Relay Mounting Bracket Fabrication pics
Source: by SeattleFSB (Seattle FSB) at SuperMotors.net
Engine Hesitation/Surge with No DTCS in 5.0 & 5.8 Engines & with DTC 179 in 4.9 Engines TSB 95-2-10 for 91-92 Bronco & 91-94 F & E Series
Source: by Ford by Ford via Chilton
Engine Management System Links, Ford
Source: by acc-electronics.com via web.archive.org
Explanation of 3-Digit Codes & MIL TSB 92-24-03 for 91-93 Bronco, F Series and Many Others
Source: by Ford via Steve83 & joshhath at FSB
Failure Mode "...is a stand in strategy in the EEC designed to maintain vehicle operation should one or more sensor inputs fail. When a sensor input is perceived to be out-of-limits by the EEC, memorized data from the computers KAM memory will be initiated. EEC continually checks the sensors against its records of normal readings during operating conditions similar to its current state. Hold on that sounds hard! Not really, randomly EEC looks at the past to see if the engine is somewhat where it usually is. If for some unknown reason a sensor is off the charts, it can’t be trusted. So instead of tuning the engine to a possible faulty sensor reading and harming the engine and drive-ability; EEC replaces the sensor reading with a best guess from a past memory. This is why unplugging the battery to fix something works against you. Unplug the battery causes EEC to memorize all the sensor data as base line and normal. If it memorizes a bad sensor it will take it longer to call it a liar. Ford did however give EEC a very broad idea of what the sensor should be reading in its permanent ROM memory, so it will catch on to failed equipment sooner..."
Source: by Ryan M (Fireguy50) at fordfuelinjection.com
Failure Mode Effects Management (FMEM) Overview; "...In FMEM mode, the computer is receiving a sensor signal that is outside the limits set by the calibration strategy. In this mode, the computer uses an alternate strategy to maintain reasonable vehicle operation in spite of the fault. The following chart lists the system faults which will turn on the CHECK ENGINE light in this mode. The error code associated with this system fault is stored in Keep Alive Memory (KAM). If the fault is no longer present, the light will turn off and vehicle will return to normal vehicle strategy. The error code stored when the light was on was not erased. This code is one of the continuous error codes and can be accessed by running the KOEO self-test..."
Source: by Ford via Steve83 (Steve, That dirty old truck) at SuperMotors.net
Failure Mode Effects Management (FMEM); FMEM is an alternate system strategy in the PCM designed to maintain vehicle operation should one or more sensor inputs fail. When a sensor input is perceived to be out-of-limits by the PCM, an alternative strategy will be initiated. The PCM will substitute a fixed in-limit sensor value and will continue to monitor the faulty sensor input. If the faulty sensor operates within limits, the PCM will return to the normal engine running strategy. Engine Running DTC 98 or 998 will be displayed when FMEM is in effect. The Malfunction Indicator Lamp (MIL)/Message will remain on when FMEM is in effect..."
Source: by miesk5 at Ford Bronco Zone Forums
Ford EEC IV Operation & Testing. Overview; "... ECT. MAP/BARO. TPS., etc. Used on most Fords. EGR Position (EVP) Feedback (PFE) EVP Linear Potentiometer..." PowerPoint Presentation READ MORE
Source: by Ryan M (FireGuy50) via powershow.com
Ford EEC IV Operation & Testing. Overview; "... ECT. MAP/BARO. TPS., etc. Used on most Fords. EGR Position (EVP) Feedback (PFE) EVP Linear Potentiometer..." PowerPoint Presentation READ MORE
Source: by Ryan M (FireGuy50) at fordfuelinjection.com
Fuel Pressure During KOER Self Test for 92; 4.9 (45-60 PSI), 5.0 (30-45 PSI), 5.8 (30-45 PSI) & 7.5 (30-45 PSI); read more for KOEO PSI
Source: by Steve83 (Steve, That dirty old truck) at SuperMotors.net
Fuel Pump Runs w/Ignition Switch Off; "...If it stays running with the truck off, then most likely you have a bad fuel pump relay; EEC Relay hanging closed; If the EEC relay goes bad, it could be sending the signal to the fuel pump relay to turn the fuel pumps on; One easy test for this is: Without the key in ignition, bump the starter over @ the starter relay using a screwdriver. If it is the EEC relay, the truck will start without the key in the ignition..." MIESK5 NOTE; from Ford EVTM; The Control Module (PCM) runs the pump{s} for one second when it receives an ignition- on signal. It also runs the pumps as long as it receives a PIP signal from the Hall-effect devices, it continues pump operation even after the key is released from START. If the PIP signals fall below 120RPM, the control module cuts off the signal to the fuel pump relay or the integrated relay control module. The pump will also run when the terminals of the fuel pump test connector are jumped. the Control module signals the pump when it receives a CRANK signal, and when the Control module gets PIP signals that the engine is running. the pump does not run if the PIP indicates the engine is not running even with ignition ON {except for that first one second}.
Source: by sackman9975 (Scott), Redwagon & miesk5 at FSB
Fuel Pump Runs w/Ignition Switch Off; "...The relay probably has the points welded. Here is a diagram of the circuit..."
Source: by Seabronc (Rosie, Fred W) at Ford Bronco Zone Forums
Fuel Pump Test & Diagram at the Diagnostic Link Connector in 84-95; "...Connect FP Relay to any ground to force the fuel pump(s) on when the key is in RUN..."
Source: by Steve83 (Steve, That dirty old truck) at SuperMotors.net
Fuel Trim; "...Fuel trim refers to adjustments being made dynamically to the base fuel table to get the proper ratio of fuel to air. Short term fuel trim refers to adjustments being made in response to temporary conditions. Long term fuel trim is used to compensate for issues that seem to be present over a much longer period. Fuel trims are expressed in percentages; positive values indicate lean (add fuel) and negative values indicate rich (subtract fuel). Fuel trim banks refer to the cylinder banks in a V style engine. Cylinder #1 is always in bank 1. Fuel trim is generally calculated by using a wide set of data values, including front O2 sensors, intake air temperature/pressure (or the more elegent air mass sensor), engine (coolant) temp, anti-knock sensors, engine load, throttle position (and change in throttle position), and even battery voltage can effect fuel trim. Long term fuel trim generally should not exceed +- 10%. Generally, and for OBD II,The HO2S detects the presence of oxygen in the exhaust and provides the PCM with feedback indicating a rich or lean condition. A correction factor is added to the fuel injector pulsewidth calculation according to the Long and Short Term Fuel Trims as needed to compensate for variations in the fuel system..."
Source: by miesk5 at FSB
Fuse "E" Inoperative could exhibit any one of the following conditions: ABS Light On, Back-Up Lamps Inoperative, Daytime Running Lamp (DRL) Inoperative, MIL On, Speedometer Inoperative, DTC 172, 173 or 41 for HO2S Failure in TSB 95-5-21 for 92-95 Bronco & F Series; On some vehicles the HO2S wires in the 12A690 (subassembly of the 14B060 battery cable) harness may become chafed READ MORE
Source: by Ford via Chilton
Fuse E Blown, ABS Light On, Back-Up Lamps Inoperative, Daytime Running Lamp (DRL) Inoperative, MIL On, Speedometer Inoperative TSB 95-02-11 for 92-95 Bronco & F Series; Miesk5 Note; also see TSB 95-5-21 for 92-95 Bronco & F Series
Source: by Ford via Steve83 (Steve, That dirty old truck) at SuperMotors.net
Ground Location pic in an 89; "...Those wires eventually connect back to the EEC case (which is grounded) and the pins on the connector that need to be grounded...but then again every ground connects to each other on a Bronco..."
Source: by kf4amu (Will H, The Beast) at FSB
Hardware Limited Operation Strategy (HLOS) Overview; "...HLOS mode is used when the system fault(s) is too extreme for the FMEM mode to handle. In HLOS mode, all software operations have stopped and the computer is running on hardware control only. The default strategy for this mode has a minimal calibration just to allow the vehicle to operate until it can be serviced. NOTE: IN HLOS MODE YOU WILL NOT GET ERROR CODES. The MIL light is turned on as a bulb check when the ignition key is first turned ON. The EEC IV computer turns off the bulb as soon as it receives the PIP (crank) signal. If the light stays on during cranking, the computer is not receiving the PIP signal..."
Source: by Ford via Steve83 (Steve, That dirty old truck) at SuperMotors.net
High Idle & Dieseling Troubleshooting Chart in a 94, from PCED Chart 7 for a 94; Preliminary Checks; Overheating or not Reaching Normal Operating Temperature, Vacuum Leaks, Throttle Plate & Linkage, Speed Control Chain Binding/Sticking, Air Intake Tube/ Intake Manifold Leaks; Check for Codes..." READ MORE
Source: by Ford via Steve83 (Steve, That dirty old truck) at SuperMotors.net
Identification, Bronco & Ford
Source: by Ryan M (Fireguy50) at fordfuelinjection.com
Identification, Bronco & Ford
Source: by smileybry at FSB
Identification, Bronco & Ford. Program Code; "Every computer has a main sticker on the 60-pin connector that identifies the computer and holds the most information about the computer. If you have an EEC in your hands and wonder what it came out of this list is for you. If you are looking for an EEC in a junkyard or swap meets this is for you too. If you just wondered what computers Ford used in which vehicle this is also for you. I would not be upset if you printed this page off for your records, in fact I recommend taking it with you so you have an advantage finding that special EEC..."
Source: by Ryan M (Fireguy50) at fordfuelinjection.com
Idle Speed Check & Adjustment
Source: by Steve83 (Steve, That dirty old truck) at FSB
Inferred Mileage Sensor Wiring Diagram in 87-89 Bronco & F series
Source: by equivalent (Beetlejuice) at SuperMotors.net
INNOVA Ford EEC IV (OBD I) Review - pics are gone
Source: by Ronnie at FSB via web.archive
Installation pics (C3P3) in a 90
Source: by BlueBeast (The Beast, JP N) at SuperMotors.net
Limp Mode; "...Fail Code conditions or Limp Mode happens when the vehicle computer recognizes a problem in it's logic. When an expected signal value from a sensor is sent to the computer and is not within the computer's programmed specifications, secondary programs are activated by the computer to strive to protect the transmission from damage the improper sensor signal might cause to occur. In other words, the computer is always expecting certain signal values from certain sensors i.e. the temperature sensor, the speed sensor, the throttle position sensor, etc. As long as these signals are what it would normally expect for the conditions and is normal based on all the other signals it is receiving from other sensors, it acts normally and accordingly. If the computer, all of a sudden, receives some crazy signal from one of the sensors that is out of the normal range expected from this sensor, it will go to emergency or secondary measures. These emergency measures vary depending on the severity of the defective signal. All this is preprogrammed into the computer's logic by the manufacturer. The manufacturer has decided that as long as a certain parameter of a particular signal is sent from a sensor to the computer, all is well. The manufacturer decided that if this signal is higher than their highest parameter or lower than their lowest parameter, something is wrong with that sensor and the computer should make someone aware of the situation and take action to try to save the vehicle systems or powertrain. Perhaps the computer will simply cause the check engine light to come on. The signal variation wasn't severe or critical to cause any mechanical failures but the vehicle's operator is made aware that he or she should have the vehicle checked out electronically to see if a minor sensor has broken down or is starting to send the odd irratic signal. This type of condition is commonly referred to as a soft code. Normal functions are not affected but if the repair is not made, performance or fuel efficiencies might suffer. Perhaps the sensor only malfunctioned one time and all other times was fine. This might be an early warning of a sensor that is beginning to fail or has a loose connector or connection. Other times the signal needed to perform operations normally is so far out of specification that the computer has no choice but to go into survival mode. With transmissions, the computer will cause the internal tranny fluid line pressure to default to high to protect clutches and bands. The transmission also turns off the shift solenoids to cause the unit to default to a single gear, usually second or third. All normal instructions to control line pressure are overridden so a hazardous slipping condition cannot occur easily. This theoretically is so that the vehicle's driver can get the damaged vehicle to the next town for repairs. This condition is commonly called Limp Mode for this reason. You limp to the next town in second or third gear only, at full line pressure so the tranny guts won't slip on your trip in. By the way, interestingly and just as a side note, if the cable harness going to your transmission was ever to become detached, severed or damaged, your transmission would also go to limp mode. The vehicle's computer would immediately sense that it has lost contact with the transmission and would set the codes and send limp mode signals to the tranny. But because the harness is severed between the computer and the transmission, no computer signals will reach the transmission. These sent signals, however, would have had the identical affect on the transmission as what taking away supplied power to the shift and line pressure solenoids has as in the case of a transmission harness being detached or cut. Due to the engineered voltage strategies of the solenoids, the transmission simply defaults to a single gear and line pressure defaults to high, all in order to limp you home. A Throttle Position Sensor that improperly sends a reading that it is wide open when in fact it is physically closed would be detected by the computer when it compared this reading with the vehicle speed sensor that perhaps is showing very slow vehicle speed. The signal, by itself can't be considered wrong but when put against all the other sensor signals of the system might cause a computer concern. The computer, at this point, unable to trust the collection of signals because together they are not making sense in it's logic, will simply go to limp mode in the transmission to protect it and make the operator aware that something is wrong with one of the sensors and a mechanic's attention is needed to correct the situation. This Fail Code Condition will show up as a code reading on a mechanic's scanner. This code will be cross referenced to a table from the manufacturer and represent a problem with a particular sensor or a group of sensors or system. It gives the mechanic a better idea of where the problem has showed up and which systems or sensors are involved in the malfunction. The table of codes and what each one means, is commonly programmed right into the scanner tool that the mechanic uses for easy reference. i.e. the scanner tool might tell the mechanic that the computer has thrown a code 35 which is the transmission fluid temperature sensor and might give the mechanic the recommended values this sensor should provide and what it in fact provided. In your electronic transmission, many important functions are controlled by the computer. Shift timing, sequence, feel, line pressure are controlled. The information from the vehicle speed sensor affects fuel injection, fuel mixture, ABS, transmission operation, etc. Load information of your engine is commonly taken primarily from the TPS (throttle position sensor) or the MAP sensor (manifold absolute pressure). This controls transmission shifting and downshifting when stepping on the gas or climbing hills. A regular scanning of the computer for any set hard or soft codes is something routinely done by most good tuneup shops these days..."
Source: by Greg O at autotransinc.com via webarchive.org
Limp Mode; "...The linkage to a throttle position sensor should use most of the rotating range of the throttle position sensor. This can be adjusted by changing the ratio of the linkage. Also, please make sure that a small amount of the sensor's travel is being used at idle. You will want a TPS voltage at idle of at least 0.35 volts. This is done to allow the TCS to detect problems with the TP sensor. For instance, if the sensor becomes disconnected or the linkage falls off, the TPS voltage will fall below the set idle threshold. If the TPS voltage goes below the idle threshold, the TCS assumes that the TPS is bad and will switch to failsafe line pressure and default shift points. This is done to prevent damage to the transmission from low line pressure and will provide a safe limp home mode..."
Source: by optishift.com
Limp Mode; "...The throttle position sensor signal takes the place of the throttle kickdown linkage on older mechanical automatics. So if the TPS is reading high or low, or has a dead spot, it can affect transmission kickdown shifts when accelerating, as well as normal upshifts and downshifts, too. If the TCM cannot get a good TPS signal, it may substitute a "calculated" throttle angle provided by the PCM over the data bus. Or, if this signal is not available, it may substitute a fixed value for the TPS signal. This will obviously affect the way it shifts (transmission typically hunts for shift points) but not necessarily cause it to go into a limp-in mode. A faulty throttle position sensor will not always set a fault code. The PCM has to be smart enough to figure out when the TPS is working properly and when it is not. Its diagnostic strategies may compare the TPS signal against engine rpm, MAP signal and/or airflow to determine if the TPS signal makes sense. If the TPS signal does not correspond to other sensor inputs that can be used to measure engine load, the PCM may set a fault code. Then again, it might not. It all depends on the self-diagnostic strategy, how sensitive it is to faults and how easily the PCM can detect problems. Under certain conditions, which may include the loss of one or more vital inputs to the TCM, the transmission will go into some kind of limp-in or defaul mode. When a serious fault is diagnosed (such as loss of an internal speed sensor signal) or a problem occurs in the wiring circuit to any of the shift solenoids, the TCM will kill the power to the transmission control relay and deenergize all of the shift solenoids. This usually causes the transmission to freeze in 2nd or 3rd gear. The transmission will remain in limp-in mode until (1) the problem is diagnosed and repaired, or (2) power to the TCM is momentarily turned off to reset the computer. This may restore normal operation temporarily, but as soon as the TCM detects the fault again, it will go back into limp-in mode..."
Source: by Larry C at aa1car.com
Location pic in 84-86
Source: by Ryan M (Fireguy50) at fordfuelinjection.com
Location pic in 87-96
Source: by Ryan M (Fireguy50) at fordfuelinjection.com
Locations in 87-91 (also see EEC Locations by Ryan M (Fireguy50) at fordfuelinjection.com; right panel)
Source: by hypertech.com via web.archive.org
Locations, Bronco & most Fords
Source: by Ryan M (Fireguy50) at fordfuelinjection.com
Malfunction Indicator Light (MIL) Introduction TSB 88-05-07 for 88 Bronco, F series, & all others
Source: by Ford via Steve83 (Steve, That dirty old truck) at fourdoorbronco.com
MPGuino Installation & Review; is an Arduino based open source fuel economy computer for most vehicles with electronic fuel injection and a vehicle speed sensor
Source: by joshhath at FSB
MPGuino Overview; is an Arduino based open source fuel economy computer for most vehicles with electronic fuel injection and a vehicle speed sensor
Source: by ecomodder.com
Multi-Function Switch (MFS), Hazard & Brake Light Disengage E4OD Torque Converter Lockup; "...Alternative connections or wiring practices are not recommended as certain modifications may result in other circuits becoming nonfunctional...Do not splice into the Powertrain System (PCM PCMV). Connecting to any component or wires to this system may adversely affect Engine/transmission operation..." read more
Source: by fleet.ford.com
Multi-Function Switch (MFS), Hazard & Brake Light MAY Disengage E4OD Torque Converter Lock-up Discussion in 92-96
Source: by members at nloc.net
Multi-Function Switch (MFS), Hazard & Brake Light MAY Disengage E4OD Torque Converter Lock-up; "...I was living with the torque converter unlocking with the R/H turn signal. And low and behold after I changed the L/H brake/turn signal bulb the torque converter stopped unlocking with the R/H turn signal. Don't ask me but it did fix it..."
Source: by Mike G & Miesk5 at Ford Bronco Zone Forums
NO CODE; IN HLOS MODE YOU WILL NOT GET ERROR CODES. Hardware Limited Operation Strategy (HLOS) Overview; "...HLOS mode is used when the system fault(s) is too extreme for the FMEM mode to handle. In HLOS mode, all software operations have stopped and the computer is running on hardware control only. The default strategy for this mode has a minimal calibration just to allow the vehicle to operate until it can be serviced. NOTE: IN HLOS MODE YOU WILL NOT GET ERROR CODES. The MIL light is turned on as a bulb check when the ignition key is first turned ON. The EEC IV computer turns off the bulb as soon as it receives the PIP (crank) signal. If the light stays on during cranking, the computer is not receiving the PIP signal..."
Source: by Ford via Steve83 (Steve, That dirty old truck) at SuperMotors.net
No Start and or Misfire, etc.; Thick Film Ignition (TFI) Testing, Overview & Diagrams, Distributor Mounted Ignition Control Module (ICM); "...Part I; In This Fast Test you'll be able to pinpoint the problem to the Ignition Control Module or the Ignition Coil or the Profile Ignition Pickup Sensor (PIP Sensor) in four easy test steps. This test will only help you in a Cranks but Does Not Start Condition. So then, before starting the tests, it's critical that you have checked and verified that there's NO SPARK present at the Ignition Coil. Why? Well, because if the Ignition Coil is sparking, it would be a clear indication that it and the Ignition Coil and the Crankshaft Position Sensor (PIP Sensor) are working. This article applies to both the Gray colored Ignition Control Module and the Black colored Ignition Control Module. The Gray colored Ignition Control Module is called the Push Start Module and the Black colored Ignition Control Module is called the Computer Controlled Dwell Module. These ignition control modules are not interchangeable. If you need the tests for the Ford Fender Mounted Ignition Control Module (ICM), click here. How Does the Ignition Control Module Work? Here's a little background information to help you diagnose this no spark condition. In a nutshell, when the system is working properly, at CRANK-UP and at all engine speeds, the Ignition Control Module controls the Ignition Coil. How? This is primarily done thru' the Profile Ignition Pickup Sensor Signal which is received by the Ignition Control Module (and also the ECM). The Ignition Control Module (ICM) upon receiving this signal, starts switching the Ignition Coil's Ground On and Off. As you may already know, it's this action that makes the Ignition Coil spark away. The Profile Ignition Pickup Sensor signal (more commonly called the PIP Signal) is critical for the Ignition Control Module to start sparking the Ignition Coil at START UP and at all engine speeds. The Profile Ignition Pickup Sensor is a Hall Effect type Crankshaft Position Sensor and produces a digital (On/Off) signal that can be seen with an LED or an oscilloscope. On an oscilloscope, it produces a digital square waveform. This sensor is located in the Distributor. What Tools do I Need for the Ignition Module Test? There are several ways to test this Ignition Control Module. An oscilloscope is the best way to check all of the input and output signals but it's not the only way. I'll show you just how. Anyway, if you have access to an oscilloscope, I have included photos of what the waveforms should look like. Whether you use a multimeter or an Oscilloscope, you'll be able to successfully diagnose this NO START CONDITION! So, here's the basic list: An LED Light. Test Light. Multimeter. A cheapie one will do. Repair Manual. For whatever other information this article does not cover. Helper. To help you crank the engine while you observe the LED light (or Test Light or Multimeter). By the way, you don't need an Automotive Scan Tool for any of these tests. We'll first check for the basics like Battery voltage and Engine Ground to the Ignition Control Module. Then we'll test the Ignition Coil Switching Signal that the Module generates in action and from the results you get you'll be able to pinpoint the problem to the Ignition Control Module (ICM) or the Ignition Coil or the Profile Ignition Pickup (PIP) Sensor or completely eliminate these as the cause of the No Start Condition. IMPORTANT- All of the tests are ON CAR TESTS, do not remove the Ignition Control Module Assembly from the vehicle (all of the figures show the Module Assembly off of the vehicle but this is just for illustration purposes only). Also, the Battery must be in a fully charged condition for all tests in this article. And lastly, this Fast Test only tests for a NO SPARK / No Start Condition. TEST INFO Circuit Descriptions; Here are brief descriptions of the circuits that we'll be testing. You'll notice that there are no wire color descriptions. This is intentional. The color of the wires in the illustration will not match the ones on your vehicle. The good news is that no matter what color the wires are (on the vehicle), the circuit descriptions DO NOT CHANGE. You will be able to successfully diagnose this NO START CONDITION with this information. IMPORTANT- It will be necessary to test some of these circuits while the engine is being cranked. Be careful, use common sense and take all necessary safety precautions. Ignition Control Module Connector; 1- Profile Ignition Pickup (PIP) Signal. 2- Spout. 3- 12 V at START. 4- 12 Volts (gray module) or IDM circuit (black module). 5- Ignition Coil Control Signal. 6- Ground. TEST 1 Checking for Power (12 V); We'll begin by checking that the Ignition Control Module is receiving 12 volts. I recommend using a wire piercing probe to accomplish all of the tests in this article. (click here to see a picture of this tool). Whatever method you use, the key here is to be careful. Remember to use common sense and take all safety precautions . IMPORTANT- The Ignition Coil, Ignition Control Module and the PIP Sensor receive 12 Volts from the same circuit. So if you test one, you test the others. 1 Put the multimeter in VOLTS DC mode. 2 It's not necessary to disconnect the Ignition Control Module (ICM). You'll probe the number 4 circuit of the Ignition Control Module Connector. 3 With the RED multimeter test lead and a suitable tool, probe the number 4 circuit wire of the Connector. 4 With the BLACK lead of the multimeter probe the BATT (-) NEGATIVE terminal. 5 Turn Key On with the Engine Off. Your Multimeter should register 12 Volts DC. CASE 1 If the Multimeter registered 12 Volts DC, All is good in the neighborhood, GO TO TEST 2. CASE 2 If the Multimeter DID NOT register 12 Volts DC, You must find out why you're missing this voltage. Without this voltage the Module, Ignition Coil, and the PIP Sensor will not work. TEST 2 Testing the Ground Circuit; Here we'll check that the Ignition Control Module (ICM) is receiving a good GROUND. This is done thru' the number 6 circuit of the Igntion Module Connector. 1 Put the multimeter in VOLTS DC mode. 2. With the BLACK multimeter test lead and a wire piercing probe, probe the Ignition Module Connector's number 6 circuit wire. 3 With the RED lead of the multimeter probe the BATT (+) POSITIVE terminal. Your Multimeter should register 12 Volts DC. CASE 1 If the Multimeter registered 12 Volts DC, All is good in the neighborhood, GO TO TEST 3. CASE 2 If the Multimeter DID NOT register 12 Volts DC, This means there is open in this circuit. Without this ground the Ignition Module will not function. Repair the circuit. EST 3 Ignition Coil Switching Signal; Now that you have verified the basics, in this test you're gonna' verify that the Ignition Control Module (ICM) is activating the Ignition Coil. Here you're going to use an LED test tool. Click here for a picture of this tool and how to make it. You can also use a Test Light for this test. Use an appropriate tool to pierce the wire and attach the LED test tool (to this tool). Be careful and use all necessary precautions. By the way, in case you want to see a more specific Ford Ignition Coil test, I’ve written one for troubleshootmyvehicle.com and you can see it here: Ford Ignition Coil Test. 1 Connect the RED wire of the LED to the Battery Positive Terminal. 2 Connect the BLACK wire of the LED to the number 5 circuit of the Ignition Control Module Connector 3 Have an assistant crank the engine. the LED test tool (or Test Light) should blink on and off as the engine is being cranked. Did this occur? CASE 1 The LED Light blinked On and Off as the engine was cranking, This means that the Ignition Control Module is triggering the Ignition Coil. So then, the Ignition Control Module is good and can been eliminated as the cause of the NO START condition. By a process of elimination, we can assume that the Ignition Coil is faulty and is the source of the NO START condition. Replace the Ignition Coil. CASE 2 The LED Light DID NOT blink On and Off as the engine was cranking, Re-check all of your connections and retry the test again. If still no light pulses on the test LED, GO TO TEST 4. TEST 4 Testing the PIP Signal; Here we'll check that the Profile Ignition Pickup Sensor (PIP) is being received by the Ignition Control Module (ICM). The PIP Signal is just Ford’s name for the Crankshaft Position Sensor Signal. Now, in case you’re wondering... the PIP Sensor is located inside the Distributor. This will be achieved by using the same LED test tool. Click here for a picture of this LED tool and how to make it. Do not use a Test Light for this test; With a suitable tool and with the key in the Off position, pierce the number 1 circuit wire of the Ignition Control Module Connector. Connect the BLACK wire of LED to the tool that is piercing the wire. Connect the RED wire of the LED to the BATTERY (+) POSITIVE terminal. Have an assistant crank the engine while you observe the LED. The LED should start to blink on and off as the engine is cranked. Is the LED blinking on and off as the engine is cranked? CASE 1 If the LED blinked On and OFF as your helper cranked the engine The Ignition Control Module (ICM) is BAD. Replace the Ignition Control Module. Here’s why: As you’re already aware, the Ignition Control Module needs: 1.) power in the form of 12 Volts. 2.) It needs a good path to ground. 3.) It needs the PIP Signal to start creating the Switching Signal the Ignition Coil needs to start sparking.. So, up until this point (in the testing) you have verified that the module does have power, that it does have ground and that it’s not creating a Switching Signal for the Ignition Coil. In this step you have confirmed that the PIP Sensor is generating a PIP Signal (as indicated by a blinking LED light). So, if the Ign. Module is getting power, ground and the PIP Signal (as evidenced by the blinking LED) is has to create a Switching Signal... if it doesn’t, it’s fried. CASE 2 The LED DID NOT blink On and OFF as your helper cranked the engine If you have no pulses, recheck all connections. Try again. If you still have no pulses. The Profile Ignition Pickup Sensor (PIP) is BAD and the cause of this NO START condition. You’ll need to replace the PIP Sensor to solve the No Start No Spark Condition on your Ford (or Mercury or Lincoln) vehicle. As mentioned earlier, the Profile Ignition Pickup (PIP) Sensor is just a Crankshaft Position Sensor located inside the Distributor. This is the Sensor that tells the Ignition Control Module (ICM) when to start activating the Ignition Coil to start Sparking away. So, if this PIP Signal is missing (as indicated by the LED not blinking on and off), the Ignition Control Module will not function..." SEE Site for Diagrams
Source: by easyautodiagnostics.com
No Start and or Misfire, etc.; Thick Film Ignition (TFI) Testing, Overview & Diagrams, Fender Mounted Ignition Control Module (ICM); "...Whether your Ford or Mercury car or truck CRANKS but DOES NOT START or runs with a MISFIRE Condition, this article is for you. With the tests I'm gonna' show you, you'll be able to pinpoint the problem to the Ignition Control Module or the Ignition Coil or the Profile Ignition Pickup Sensor (PIP Sensor) or the Spark Plug Wires or the Distributor Cap. This article applies to both the Gray colored Ignition Control Module and the Black colored Ignition Control Module. The Gray colored Ignition Control Module is called the Push Start Module and the Black colored Ignition Control Module is called the Computer Controlled Dwell Module. These Ignition Control Modules (ICM) are not interchangeable but are tested in the exact same way. Also, the photos (in the image viewer) show some of the tests performed on a V8 engine. This might make you think that they don’t apply to your 3.0L, 3.8L V6... well nothing could be further from the truth. All of these test steps apply to both the V8, V6 and L6 Ford engines. For a complete list of applications, see the list at the bottom of the page. As you can see from the image of the Ignition Control Module (in the image viewer on the left), the tests apply to the fender mounted Ford Ignition Control Module. If you need to test the Distributor Mounted Ford Ignition Control Module, click here: How to test the Ford Distributor Mounted Ignition Control Module (ICM). To test Ford Coil-on-Plug Ignition Coils (4.6L and 5.4L V8 engines), click here: Ford Coil-on-Plug (COP) Ignition Coil Tests. Here's a little background information to help you diagnose this no spark condition. In a nutshell, when the system is working properly and you turn the key to crank and start your Ford car or truck: 1.The Distributor shaft starts to rotate which causes the PIP (Profile Ignition Pickup) Sensor to start generating its Crankshaft Position Signal. 2.The Ignition Control Module (ICM), upon receiving this PIP Signal, starts to 'open and close' the Ignition Coil's primary current. As you might already be aware, it's this action that makes the Ignition Coil Spark.3.The Fuel Injection Computer also receives the PIP Signal at the same time that the Ignition Module does.4.Once the engine STARTS, the Fuel Injection Computer takes over the Ignition Timing.The PIP Sensor is at the heart of this Fender Mounted Ignition Control Module and Ignition System. Here are some useful facts that you should be aware of about the PIP (Profile Ignition Pickup) Sensor: 1.The PIP Sensor is located in the Distributor.2.It's a Hall Effect type Sensor.3.It produces a digital square wave if its Signal is tested on an Oscilloscope. 4.This signal can also be tested with an LED Light (which is the method I'll use in this article). 5. 5.If it goes BAD, the your Ford car or truck will CRANK but NOT START. No expensive tools are required to test this type of Ignition System. Now, having said that, there some very specific tools that I recommend to use for the tests. So, here's the basic list:".. READ MORE
Source: by easyautodiagnostics.com
No Start; "Here is a quick check for no-startcondition. Turn the ignition key to da ON position to see if the “Check Engine Light" (CEL) turns on. If the CEL does NOT Light Up & it has in past before this NO START condition began, check the EEC relay"
Source: by miesk5 at Ford Bronco Zone Forums
No Start; & Relay Connection pic in 92-96; "...The relay trigger wire (LG/R) comes from the ignition switch via the clutch switch or MLPS and should only be hot with the key in START and either the clutch fully depressed, OR the auto shifter in P or N. The solenoid trigger wire goes to the small terminal on the starter. If the relay fails, bridge between the 2 large studs to send power to the solenoid. If the starter still doesn't spin, crawl under the truck, remove the red plastic cover, and BRIEFLY bridge between the 2 large studs on the solenoid (using a heavy metal object with an insulated grip, like a screwdriver) to spin the starter (it won't engage the flywheel or crank the engine). If it still doesn't spin, replace the starter. 130A & heavier alternators use 2 fusible link wires. The Yellow wire goes to the stud on the side of the power distribution box, and feeds all other factory loads on the vehicle..."
Source: by Steve83 (Steve, That dirty old truck) at SuperMotors.net
Open Loop & Closed Loop Overview; "...Open Loop fuel control, the ECU takes its best guess at the injector Pulse Width (PW) to achieve a desired A/F ratio. With a Closed Loop system, the ECU can actually use Exhaust Gas Oxygen sensors to check and see how well it's doing for fuel control, and make adjustments as necessary, including updating its programming..." READ MUCH MORE
Source: by Ed H at musclemustangfastfords.com
Overview; "...The engine control systems are used in conjunction with either a throttle body (CFI) injection or multi-point (EFI and SEFI) injection fuel delivery system or feedback carburetor systems depending on the year, model and powertrain. Although the individual system components vary slightly, the electronic control system operation is basically the same. The major difference is the number and type of output devices being controlled by the ECA. One of these electronic test devices has become the on-board computer itself. The Powertrain Control Modules (PCM), sometimes called the Electronic Control Assembly (ECA), used on toadies vehicles has a built in self testing system. This self test ability is called self-diagnosis. The self-diagnosis system will test many or all of the sensors and controlled devices for proper function. When a malfunction is detected this system will store a fault code in memory that's related to that specific circuit. You can access the computer to obtain fault codes recorded in memory by using an analog voltmeter or special diagnostic scan tool. This will help narrow down what area to begin testing. There are 3 electronic fuel control systems used by Ford Motor Company. These systems all operate using similar components and on-board computers. Self-Diagnostic on these systems will vary, but, the basic fuel control operation is the same. Ford uses the following systems: EEC-IV and EEC-V engine control system: used on most domestic built Ford vehicles since 1984. Non-NAAO EEC engine control system: used on import built Ford vehicles, referred to as Non-NAAO cars.MCU feedback carburetor system: used on most Ford vehicles before 1984 and some later model vehicles equipped with a V8 engine and feedback carburetor. Most Ford vehicles made after 1983 use the 4th generation Electronic Engine Control system, commonly designated EEC-IV..." READ MORE for Reading Codes & Diagnostic Trouble Codes (DTC's)
Source: by Ford via arrc.epnet.com
Powertrain Electronic Control Strategy Book
Source: by Ford via Ryan M (Fireguy50) at fordfuelinjection.com
PSOM & Odometer Not Working "..due to Bad diode in the alternator that put a rf signal into the speed sensor line. It turned out to be a bad diode in the alternator that put a rf signal into the speed sensor line. I unplugged the alternator electrical connector and it went away. I am a mechanic by trade and this was on a 2001 superduty that would die when it hit 1100rpm. I was doing my key on engine running selftest when the scanner could not complete it due to excessive vss. So i monitered my vss and when my target rpm was hit the pcm would have the speed limiter kick in and since there was no laod on the engine it would stall. Naturally I started unplugging stuff untill my interferance signal went away..."
Source: by Mr Bell & miesk5 at FSB
Re-Wiring 460 EFI Swap in a 79; "...OK, as usual, you will need, of course, the engine and accessories (if you want to run a serpentine belt), the computer and wiring harness (preferably out of a late 80'sor early 90's with either a C6 or a Manual Trans, can be either E or F series), as well you will need a fuel system that will be adequate to handle 40+ psi of fuel pressure, and a fuel pump that will deliver that 40+ psi of pressure (recommend a factory pump setup, or an aftermarket hi-pressure in-line fuel pump) (side note: I am taking that you have already taken out the old engine and have done the nessasary steps to install the 460 if the vehicle has not already had a Big Block in it already - 351m and 400 not included as big block). To start, you will need to do some re-wiring in the engine compartment, and also with the engine wiring harness. V+ Constant - Black/Orange - Yellow (EEC Power Relay/Fuel Pump relay). Switched - Red/Lt.Green - White - Grey/Yellow - Brown/White (HEGO, Coil, EEC Power); Fuel Pump V+ - Pink/Black (or it can be Orange/Lt.Blue); V- - Black/Lt.Green - Black; Starter V+ - Red/Blue (it also connects to the distributor); Coolant Temp Sensor - Red/White, and Oil Pressure Sensor - White/Red; A/C Compressor - Black/Yellow (if you have no A/C, you can hook it up to a switch 12V, and use it as a bit of a high idle, I think that itwill take it up to 1100 - 1200 rpm; Speed Sensor - Dk.Green/White and Grey/Black (I don't use this, I only put this in here so you know about them), I have had no problems with the truck, not running the sensor, it has not kicked up some engine codes and or suffered any problems; Reverse Lights - Black/Pink and or Purple/Orange; Neutral Saftey Switch - Red/Blue; Check Engine Light - Brown, or Brown/Red;Well, that should be all the wiring color codes and attachments....now comes the actual swap..." READ MORE
Source: by Tom (origin, Mr.TroubleMaker) at nelson.macd.ca site via web.archive.org
Relay (BROWN Connector, next GREEN FP Relay Connector Under hood behind air cleaner assy) Location pic in a 90 and all up to 91
Source: by Need4racin (The 90 Bronco, Dean) at FSB
Relay (PCM) Wiring Diagram in a 95 (see #2)
Source: by Seabronc (Rosie, Fred W) at Ford Bronco Zone Forums
Relay Color Codes for Troubleshooting/Swapping to Bosch Style Relays in all pre-'92 EFI Bronco & F-series
Source: by Steve83 (Steve, That dirty old truck) at SuperMotors.net
Relay Connector Location Diagram in a 90
Source: by SeattleFSB (Seattle FSB) at SuperMotors.net
Relay Connector Location Diagram, Engine Area in a 91 4.9
Source: by Ford via chiltonlibrary.com
Relay is "...(BROWN Connector, next to GREEN FP Relay Connector Under hood behind air cleaner assy)..." Location pic in a 90 and all up to 91
Source: by Need4racin (The 90 Bronco, Dean) at FSB
Relay Location Depiction in 84-86
Source: by Ryan M (Fireguy50) at FSB
Relay Location Depiction in 84-86
Source: by Ryan M (Fireguy50) at fordfuelinjection.com
Relay Location in a 90; on driver's side fender apron
Source: by Seattle FSB (SeattleFSB) at SuperMotors.net
Relay Location in an 85; "...eec relay is behind the dash, roughly above the gas pedal and to the right a little behind the blower switch about 3 inches..."
Source: by Wolfgangpeanut at FSB
Relay Location in an 85; "...It is just behind the engine computer, above the gas pedal. Look in back of the rear defroster switch about 3 inches. When you find it check all you wiring to connector..."
Source: by JimDez at FSB
Relay Location in an 86; "...On some 86's (like mine) you will find the EEC Relay in the cab to thr right of the gas pedal...sorta where your ash tray would be..."
Source: by Xris at FSB
Relay Location in Power Distribution Box (PDB) in a 93 Bronco; Click next to see the Diagram
Source: by Troll Banned (Bronco Rob, BroncoRob) at SuperMotors.net
Relay Location in Power Distribution Box Diagram in a 92 Bronco & F-Series
Source: by Steve83 (Steve, That dirty old truck) at SuperMotors.net
Relay Location in Power Distribution Box Diagram in a 94 Bronco & F-Series
Source: by Steve83 (Steve, That dirty old truck) at SuperMotors.net
Relay Location in Power Distribution Box Diagram in a 95
Source: by Seabronc (Rosie, Fred W) at Ford Bronco Zone Forums
Relay Location in Power Distribution Box Diagram in a 95
Source: by Seabronc (Rosie, Fred W) at Ford Bronco Zone Forums
Relay Operational Sequence for Fuel Pump and Relay, Depiction & Wiring Diagram in a 94; "...When the ignition is switched to the ON position, it turns the EEC Power Relay on. The EEC Power Relay provides power to the EEC-IV processor and the control side of the fuel pump relay. Power for the fuel pump is supplied through a fuse link or high current fuse attached to the starter solenoid (battery side). From the fuse link or high current fuse, current flow is through the fuel pump relay and Inertia Fuel Shutoff (IFS) switch to the fuel pump. The IFS switch is a safety device used to shut off the fuel pump in the event of a collision. If the IFS switch is "tripped," it must be reset by depressing the white or red button on the top of the switch. The fuel pump relay is controlled by the Powertrain Control Module (PCM). When the ignition switch is turned to the ON position, the fuel pump will operate. If the ignition switch is not turned to the START position, the PCM will shut the fuel pump off after approximately one second. The PCM will operate the fuel pump when the ignition is in the START position to provide fuel while cranking.After the engine starts, the PCM will continue to operate the fuel pump unless the engine stops, engine speed drops below 120 rpm, or the IFS switch is "tripped." Note: Grounding the FP lead at the DLC will allow the pump to run continuously with the ignition switch on..." READ MORE
Source: by Ford via thedieselstop.com
Relay Overview, Depiction & Wiring Diagram in a 94
Source: by Ford via thedieselstop.com
Relay Pin-Outs (Partial) in 88-89 & 90-91 Bronco 4.9; 88-90, 91 & 92-93 Bronco 5.0; 88-91 & 92-93 Bronco 5.8; Looking Into Harness Connectors in Ford Electronic Engine Control Overview, Chapter 12, of Ford Fuel Injection and Electronic Engine Control: How to Understand, Service and Modify, 1988-1993
Source: by Charles O. Probst via yunost.ru
Relay Swap with Horn Relay in 92-96 to Test FP Relay
Source: by Steve83 (Steve, That dirty old truck) at FSB
Relay Swapping to Bosch Type & Color Codes in all pre-'92 EFI Bronco & F-series; "...Working on ONE relay at a time, remove the terminals from the stock connector & discard it. I collected these Bosch-style sockets in junkyards, but they're available at most parts stores, from Ford, or several online suppliers like RJMInjectionTech.com as crimp-on kits for a near-factory look. Being careful to connect the wires to the proper terminals (using the list below), securely connect the old wires to the terminals of the new sockets. Try to keep the wires the same length so there's not a huge ratnest. EEC PWR 30 - Y (battery always 12V) 87 - Bu, DB, R (out to EEC) 85 - Wh/LB, R/LG (12V in from ig.sw.) 86 - Bk/LG, Bk (ground); FP: 30 - Y (battery always 12V) 87 - Pk/Bk, Br, DG/Y (out to inertia sw.) 85 - R (12V in from EEC PWR relay) 86 - T/LG, LB/Or (ground from EEC)...It's OK to reverse 30 with 87, or 85 with 86 on either relay. It's possible to just use common insulated flat blade terminals to connect the bare wires to the relay terminals without a socket, but it's not as secure or convenient. Now the truck will be MUCH more reliable, and can use the cheaper, heavier-duty, more common ISO relays that are easier to swap. Tape up the harness & secure the relays to a safe mounting location. Not all relays have mounting tabs like these, but the sockets or harness can be zip-tied to something solid..."
Source: by Steve83 (Steve, That dirty old truck) at SuperMotors.net
Relay Swapping to Bosch Type in all pre-'92 EFI Bronco & F-series
Source: by Steve83 (Steve, That dirty old truck) at FSB
Relay Test, Ford (Bosch Type); "...Fuel pump relay switches, and other relays are similar to the starter solinoid, in that they make a high amperage connection through a switched low amperage connection. There are two smaller connections, and two larger connections. TO test it, apply 12v to one of the smaller connections, and ground the other smaller connection. (I used to small aligator clipped jumper wries separated by a small piece of cardboard to keep them from shorting against each other.) You should hear it click. Then check for continuity between the two larger connections.Now remove the power from the smaller connections and recheck continuity between the larger connections.With power, one should have continuity, without power it should be an open circuit (no continuity)..."
Source: by Poppy at fordforumsonline.com
Relay Wiring Diagram (Partial) in 92-95 Bronco & F Series
Source: by Steve83 (Steve, That dirty old truck) at SuperMotors.net
Relay Wiring Diagram for 84 Bronco & F-Series (partial); "...Similar to 80-91 Bronco & F-Series..."
Source: by Steve83 (Steve, That dirty old truck) at SuperMotors.net
Relay Wiring Diagram in a 90
Source: by Seattle FSB (SeattleFSB) at SuperMotors.net
Relay Wiring Diagram in a 94 from EVTM
Source: by Mikey350 at SuperMotors.net
Relay Wiring Diagram in a 95
Source: by SeattleFSB (Seattle FSB) at SuperMotors.net
Relay Wiring Diagram in an 84
Source: by toddcomputer.com
Relay Wiring Diagram in an 86 & Ford truck
Source: by Agnem (The Moosestang) at webshots.com
Relay Wiring Diagram in an 86 5.0
Source: by Ryan M (FireGuy50) at fordfuelinjection.com
Relay Wiring Diagram in an 89
Source: by SeattleFSB (Seattle FSB) at SuperMotors.net
Relay Wiring Diagram in an 89 5.0, 5.8 & 7.5
Source: by Seabronc (Rosie, Fred W) at Ford Bronco Zone Forums
Relay, Bosch Overview, Schematics, etc.
Source: by Craig U at classictruckshop.com
Relay; "...An inertia switch is used as a safety device in the fuel system. The inertia switch is located in the cab, generally under the dashboard on the right side. It is designed to open the fuel pump power circuit in the event of a collision. The switch is reset by pushing each of 2 buttons on the switch simultaneously (some models use switches with only one reset button). The inertia switch should not be reset until the fuel system has been inspected for damage or leaks. When the ignition switch is ON, it turns the EEC power relay ON. The EEC power relay provides power to the powertrain control module (PCM) and the control side of the fuel pump relay. Power for the fuel pump(s) is supplied through a fuse link or high current fuse attached to the starter solenoid (battery side). From the fuse link or high current fuse, current flows through the fuel pump relay and inertia switch to the fuel pump(s). The fuel pump relay is controlled by the PCM. When the ignition switch is turned ON, the fuel pump(s) will operate. If the ignition switch is not turned to the START position the PCM will shut the fuel pump(s) OFF after 1 second. The PCM will operate the fuel pump(s) operate the fuel pump(s) when the ignition switch is turn to START position to provide fuel while cranking. After the engine starts, the PCM will continue to operate the fuel pump(s) unless the engine stops, drops below 120 rpm or the inertia switch is tripped..." (under license from Delmar Publishers, comb of Chilton/Nichols/Delmar & Haynes); some may be incorrect, as reported by Seabronc, thanks Seabronc! NEW SITE URL!!! MUST REGISTER TO VIEW; select year, make, model, engine size and go to appropriate section
Source: by Chilton via AutoZone
Removal in a 95 7.3L C-350 (Centurion Conversions)
Source: by BJS at SuperMotors.net
Removal in a 95 7.3L C-350 (Centurion Conversions)(must register to view pics, so see his SM site for pics)
Source: by BJS at fourdoorbronco.com
Repair Price Estimator, Bronco from 90-96 and other Fords; including labor & parts, shops in area, by Zip Code
Source: by RepairPal
Replacement, when to and when not to Tips
Source: by AutoTap® autotap.com
Rotunda EEC-IV Monitor 007-0047F Description and Installation
Source: by Ford via techcapri.com
Rotunda EEC-IV Recorder Description and Installation
Source: by Ford via techcapri.com
Rotunda Superstar II 007-0041a Instructions
Source: by Ford via performanceprobe.com
Rotunda Test Equipment Depiction & Info from 94 PCED, EEC-IV Quick Test Procedures and Appendix
Source: by Ford via thedieselstop.com
Scan Tool Instructions; Actron, Auto X-Ray, KAL
Source: by tradervar.com
Scan Tool Won’t Initiate Self-Test Due to Poor Grounds, Corroded Wiring, etc.; read more on how to Ground the STI & Proceed w/ Test; miesk5 Note; Steve83 advises; "...If the CEL is burned out, connect CEL (C) to a 12V test light, and the light's other terminal to a 12V source on the same vehicle..."
Source: by Jeremy M (Big '92, jermil01) at SuperMotors.net
Scan Tool Won’t Initiate Self-Tests Troubleshooting in EEC-IV; SIG-RTN, Self-Test Output circuit, etc.; miesk5 Note; Steve83 advises; "...If the CEL is burned out, connect CEL (C) to a 12V test light, and the light's other terminal to a 12V source on the same vehicle..."
Source: by Ryan M (Fireguy50) at fordfuelinjection.com
Scan Tool Won’t Initiate Self-Tests, STO/MIL circuit shorting intermittently to ground; "...Occasionally, there are reports of the Malfunction Indicator Lamp (MIL) "Check Engine" or "Service Engine Soon" lamp being lit with no Self-Test codes in Continuous Memory; in MIL Explanation with No Self Test Codes TSB 92-24-3 by Ford for 91-93; The EEC processor will erase a Continuous Memory code if the concern that caused it has not been present for 40 or 80 warm-up cycles, depending on the vehicle. A warm-up cycle occurs when the vehicle is started with the coolant temperature below 120° F (49° C) and then shutdown with the coolant temperature above 150° F (66° C). If a vehicle is brought in for service with a MIL complaint and the vehicle is driven or otherwise allowed to warm-up before Self-Test is run, the code may be cleared before the technician tests it. 4) Grounded STO/MIL Circuit The processor controls the MIL by grounding the STO/MIL circuit (Pin 17). If this circuit shorts to ground, whether the processor is controlling it or not, the MIL will be lit. Starting in 1991, if the processor has lit the MIL, it will hold it on for a minimum of 10 seconds. If the MIL flashes quickly, the concern is probably the STO/MIL circuit shorting intermittently to ground..."; "...The self-test plugs were mounted on the passenger side fender on 1985-86 EFI trucks; The self-test plugs are located along the driver's side fender behind the air filter box on 87-95 EFI trucks..."; miesk5 NOTE; Self-Test Input (STI) is the Pin in the Lt gray Connector and Signal Return Ground (STO/SIGRET) is Pin E in black Connector in 87-95; The engine temperature must be greater than 50°F (10°C) to pass the KOEO Self-Test and greater than 180°F (82°C) to pass the KOER Self-Test. Run it around to heat the engine up and shift thru all gears incl Reverse. Then turn off all accesories/lights, etc. Make sure A/C is off and transmission is in Park (automatic) or in Neutral for a Manual & release clutch. Do Key On Engine Off (KOEO) portion first. Fix any codes from the KOEO test before you do the running test (KOER, key on, engine running). Look Codes up in my broncolinks.com site using the new Search function.; miesk5 Note; Steve83 advises; "...If the CEL is burned out, connect CEL (C) to a 12V test light, and the light's other terminal to a 12V source on the same vehicle..."
Source: by Ford via miesk5 at cc
Scan Tool Won’t Initiate Self-Tests; malfunctioning Electronic Engine Control (EEC) Relay in a 92; Jeremy wrote on Page 2; "...I was able to get codes the old fashioned way by counting the flashes on dashboard, so I think that would eliminate any prospect of it being something in the wiring; ....As luck would have, it appears that changing out the old EEC relay did the trick. At first I didn't think it would. Instead of using wire from the self test connector to the battery, I plugged it directly into the connector on the tool and went through the KOEO code retreival process and lo and behold I got codes..I even got the KOER test to work as well..."; miesk5 Note; Steve83 advises; "...If the CEL is burned out, connect CEL (C) to a 12V test light, and the light's other terminal to a 12V source on the same vehicle..."
Source: by Jeremy M (Big '92, jermil01) & miesk5 at FSB
Scan Tool Won’t Initiate Self-Tests; Vehicle Battery goes Dead, Short Solenoid Body Life, 4th Gear Starts in D/High Pressure may be caused by a malfunctioning Electronic Engine Control (EEC) Relay. The EEC relay is controlled by 12 volts from the ignition switch and is responsible for supplying voltage to the computer and solenoid body. If the relay contacts stick open, the complaints are as follows: Gas engine applications won’t start, Diesel will start and run, but have 4th gear starts in D, 2nd gear in 2 and 1, and maximum line pressure. If the contacts are stuck closed, the complaints may be as follows: Both gas and diesel engine application: Scan tool won’t work, vehicle battery goes dead, short solenoid body life. Note: Watch for corroded relay terminals and connectors on 89-91 E-series vans. The relay is very close to the right side battery and prone to corrosion problems especially on diesel ambulances..." read more, Diagrams are gone
Source: by ATC-Distribution Group Inc. atcdg.com via web.archive.org
Self Test & Diagnostic Trouble Codes (DTCs) 2 & 3 digits, Bronco & Ford; "...The self-test plugs were mounted on the passenger side fender on 1985-86 EFI trucks; The self-test plugs are located along the driver's side fender behind the air filter box on 87-95 EFI trucks..."; miesk5 NOTE; Self-Test Input (STI) is the Pin in the Lt gray Connector and Signal Return Ground (STO/SIGRET) is Pin E in black Connector in 87-95; The engine temperature must be greater than 50°F (10°C) to pass the KOEO Self-Test and greater than 180°F (82°C) to pass the KOER Self-Test. Run it around to heat the engine up and shift thru all gears incl Reverse. Then turn off all accesories/lights, etc. Make sure A/C is off and transmission is in Park (automatic) or in Neutral for a Manual & release clutch. Do Key On Engine Off (KOEO) portion first. Fix any codes from the KOEO test before you do the running test (KOER, key on, engine running). Look Codes up in my broncolinks.com site using the new Search function.; miesk5 Note; Steve83 advises; "...If the CEL is burned out, connect CEL (C) to a 12V test light, and the light's other terminal to a 12V source on the same vehicle..."
Source: by Steve via Havack (Ben P) at broncodata.com via replay.waybackmachine.org
Self Test & Diagnostic Trouble Codes (DTCs) 2 & 3 digits, Bronco & Ford; "...The self-test plugs were mounted on the passenger side fender on 1985-86 EFI trucks; The self-test plugs are located along the driver's side fender behind the air filter box on 87-95 EFI trucks..."; miesk5 NOTE; Self-Test Input (STI) is the Pin in the Lt gray Connector and Signal Return Ground (STO/SIGRET) is Pin E in black Connector in 87-95; The engine temperature must be greater than 50°F (10°C) to pass the KOEO Self-Test and greater than 180°F (82°C) to pass the KOER Self-Test. Run it around to heat the engine up and shift thru all gears incl Reverse. Then turn off all accesories/lights, etc. Make sure A/C is off and transmission is in Park (automatic) or in Neutral for a Manual & release clutch. Do Key On Engine Off (KOEO) portion first. Fix any codes from the KOEO test before you do the running test (KOER, key on, engine running). Look Codes up in my broncolinks.com site using the new Search function.; miesk5 Note; Steve83 advises; "...If the CEL is burned out, connect CEL (C) to a 12V test light, and the light's other terminal to a 12V source on the same vehicle..."
Source: by broncoii.org
Self Test - & Connector Location & pics, Bronco & Ford (under license from Delmar Publishers, comb of Chilton/Nichols/Delmar & Haynes); some may be incorrect, as reported by Seabronc, thanks Seabronc! NEW SITE URL!!! MUST REGISTER TO VIEW; select year, make, model, engine size and go to appropriate section; miesk5 Note; Steve83 advises; "...If the CEL is burned out, connect CEL (C) to a 12V test light, and the light's other terminal to a 12V source on the same vehicle..."
Source: by Chilton via AutoZone
Self Test - & Connector Location, Bronco & Ford; "...The self-test plugs were mounted on the passenger side fender on 1985-86 EFI trucks; The self-test plugs are located along the driver's side fender behind the air filter box on 87-95 EFI trucks..."; miesk5 NOTE; Self-Test Input (STI) is the Pin in the Lt gray Connector and Signal Return Ground (STO/SIGRET) is Pin E in black Connector in 87-95; The engine temperature must be greater than 50°F (10°C) to pass the KOEO Self-Test and greater than 180°F (82°C) to pass the KOER Self-Test. Run it around to heat the engine up and shift thru all gears incl Reverse. Then turn off all accesories/lights, etc. Make sure A/C is off and transmission is in Park (automatic) or in Neutral for a Manual & release clutch. Do Key On Engine Off (KOEO) portion first. Fix any codes from the KOEO test before you do the running test (KOER, key on, engine running). Look Codes up in my broncolinks.com site using the new Search function.; miesk5 Note; Steve83 advises; "...If the CEL is burned out, connect CEL (C) to a 12V test light, and the light's other terminal to a 12V source on the same vehicle..."
Source: by thorssell.net
Self Test - & DTCs 2 digits & some Possible Causes, MANY CODES!
Source: by Tomco Inc. tomco-inc.com
Self Test - & Connector Location & pics in a 90; "...All you need is a paper clip to pull codes on an EEC-IV system. Just short the 2 locations as shown, turn the key forward and count the CEL flashes. EASY. Check your Haynes manual or go to Fordfuelinjection.com for an explanation of codes. different angle just to make sure there is no mistake which ones to short. There are other ways to pull codes but this is by far the easiest..." MIESK5 NOTE; Self-Test Output (STO) is the Pin in the Lt gray Connector and Signal Return Ground (SIGRET) is Pin E in black Connector; miesk5 Note; Steve83 advises; "...If the CEL is burned out, connect CEL (C) to a 12V test light, and the light's other terminal to a 12V source on the same vehicle..."
Source: by Bob K (RLKBOB) at SuperMotors.net
Self Test - & Connector Location Diagram, Engine Area in a 92 5.0 & 5.8; "...The self-test plugs were mounted on the passenger side fender on 1985-86 EFI trucks; The self-test plugs are located along the driver's side fender behind the air filter box on 87-95 EFI trucks..."; miesk5 NOTE; Self-Test Input (STI) is the Pin in the Lt gray Connector and Signal Return Ground (STO/SIGRET) is Pin E in black Connector in 87-95; The engine temperature must be greater than 50°F (10°C) to pass the KOEO Self-Test and greater than 180°F (82°C) to pass the KOER Self-Test. Run it around to heat the engine up and shift thru all gears incl Reverse. Then turn off all accesories/lights, etc. Make sure A/C is off and transmission is in Park (automatic) or in Neutral for a Manual & release clutch. Do Key On Engine Off (KOEO) portion first. Fix any codes from the KOEO test before you do the running test (KOER, key on, engine running). Look Codes up in my broncolinks.com site using the new Search function.; miesk5 Note; Steve83 advises; "...If the CEL is burned out, connect CEL (C) to a 12V test light, and the light's other terminal to a 12V source on the same vehicle..."
Source: by Ford via Jem270 at Supermotors.net
Self Test - & Connector Location Info & pics in a 90; "...The self-test plugs were mounted on the passenger side fender on 1985-86 EFI trucks; The self-test plugs are located along the driver's side fender behind the air filter box on 87-95 EFI trucks..."; miesk5 NOTE; Self-Test Input (STI) is the Pin in the Lt gray Connector and Signal Return Ground (STO/SIGRET) is Pin E in black Connector in 87-95; The engine temperature must be greater than 50°F (10°C) to pass the KOEO Self-Test and greater than 180°F (82°C) to pass the KOER Self-Test. Run it around to heat the engine up and shift thru all gears incl Reverse. Then turn off all accesories/lights, etc. Make sure A/C is off and transmission is in Park (automatic) or in Neutral for a Manual & release clutch. Do Key On Engine Off (KOEO) portion first. Fix any codes from the KOEO test before you do the running test (KOER, key on, engine running). Look Codes up in my broncolinks.com site using the new Search function.; miesk5 Note; Steve83 advises; "...If the CEL is burned out, connect CEL (C) to a 12V test light, and the light's other terminal to a 12V source on the same vehicle..."
Source: by Gordon at Ford Bronco Zone Forums
Self Test - & Connector Location Info in 84-86; "...located on R wheelwell near starter relay..."; miesk5 Note; Steve83 advises; "...If the CEL is burned out, connect CEL (C) to a 12V test light, and the light's other terminal to a 12V source on the same vehicle..."
Source: by Steve83 (Steve, That dirty old truck) at SuperMotors.net
Self Test - & Connector Location Info in 87-95; "...The self-test plugs were mounted on the passenger side fender on 1985-86 EFI trucks; The self-test plugs are located along the driver's side fender behind the air filter box on 87-95 EFI trucks..."; miesk5 NOTE; Self-Test Input (STI) is the Pin in the Lt gray Connector and Signal Return Ground (STO/SIGRET) is Pin E in black Connector in 87-95; The engine temperature must be greater than 50°F (10°C) to pass the KOEO Self-Test and greater than 180°F (82°C) to pass the KOER Self-Test. Run it around to heat the engine up and shift thru all gears incl Reverse. Then turn off all accesories/lights, etc. Make sure A/C is off and transmission is in Park (automatic) or in Neutral for a Manual & release clutch. Do Key On Engine Off (KOEO) portion first. Fix any codes from the KOEO test before you do the running test (KOER, key on, engine running). Look Codes up in my broncolinks.com site using the new Search function.; miesk5 Note; Steve83 advises; "...If the CEL is burned out, connect CEL (C) to a 12V test light, and the light's other terminal to a 12V source on the same vehicle..."
Source: by Steve83 (Steve, That dirty old truck) at SuperMotors.net
Self Test - & Connector Location Info in an 86; "...My Test Connectors and Battery are on the "right side" (passenger) behind a black EGR Vacuum Reservoir, my BKO is an 86 but as long as the Code Reader and Test Connector Plugs are the same it should be fine..."
Source: by JKossarides ("The Bronco", Jean) at FSB
Self Test - & Connector Location pic in 84-86; "...located on R wheelwell near starter relay..."
Source: by Steve83 (Steve, That dirty old truck) at SuperMotors.net
Self Test - & Connector Location pic in a 93; labeled DLC
Source: by Steve83 (Steve, That dirty old truck) at SuperMotors.net
Self Test - & Connector Location pics & Connector Diagram w/Pin Numbers; "...The self-test plugs were mounted on the passenger side fender on 1985-86 EFI trucks; The self-test plugs are located along the driver's side fender behind the air filter box on 87-95 EFI trucks..."; miesk5 NOTE; Self-Test Input (STI) is the Pin in the Lt gray Connector and Signal Return Ground (STO/SIGRET) is Pin E in black Connector in 87-95; The engine temperature must be greater than 50°F (10°C) to pass the KOEO Self-Test and greater than 180°F (82°C) to pass the KOER Self-Test. Run it around to heat the engine up and shift thru all gears incl Reverse. Then turn off all accesories/lights, etc. Make sure A/C is off and transmission is in Park (automatic) or in Neutral for a Manual & release clutch. Do Key On Engine Off (KOEO) portion first. Fix any codes from the KOEO test before you do the running test (KOER, key on, engine running). Look Codes up in my broncolinks.com site using the new Search function.; miesk5 Note; Steve83 advises; "...If the CEL is burned out, connect CEL (C) to a 12V test light, and the light's other terminal to a 12V source on the same vehicle..."
Source: by Fireguy50 (Ryan M) at fordfuelinjection.com
Self Test - & Connector Location Video in an 86; "...My Test Connectors and Battery are on the "right side" (passenger) behind a black EGR Vacuum Reservoir..."
Source: by JKossarides ("The Bronco", Jean) at SuperMotors.net
Self Test - & Connector Pin-Out Diagram in 87-95; "...The self-test plugs were mounted on the passenger side fender on 1985-86 EFI trucks; The self-test plugs are located along the driver's side fender behind the air filter box on 87-95 EFI trucks..."; miesk5 NOTE; Self-Test Input (STI) is the Pin in the Lt gray Connector and Signal Return Ground (STO/SIGRET) is Pin E in black Connector in 87-95; The engine temperature must be greater than 50°F (10°C) to pass the KOEO Self-Test and greater than 180°F (82°C) to pass the KOER Self-Test. Run it around to heat the engine up and shift thru all gears incl Reverse. Then turn off all accesories/lights, etc. Make sure A/C is off and transmission is in Park (automatic) or in Neutral for a Manual & release clutch. Do Key On Engine Off (KOEO) portion first. Fix any codes from the KOEO test before you do the running test (KOER, key on, engine running). Look Codes up in my broncolinks.com site using the new Search function.; miesk5 Note; Steve83 advises; "...If the CEL is burned out, connect CEL (C) to a 12V test light, and the light's other terminal to a 12V source on the same vehicle..."
Source: by Steve83 (Steve, That dirty old truck) at SuperMotors.net
Self Test - & Connector; "..This is a cheap & easy upgrade to any EEC-IV vehicle: a simple jumper wire twisted into the harness behind the DLC makes pulling codes or triggering the fuel pump relay quick & convenient. ..."
Source: by Steve83 (Steve, That dirty old truck) at SuperMotors.net
Self Test - & Connectors Pic in an 86; "...My Test Connectors and Battery are on the "right side" (passenger) behind a black EGR Vacuum Reservoir..."
Source: by JKossarides ("The Bronco", Jean) at SuperMotors.net
Self Test - & DTCs 2 digits & some Possible Causes, MANY CODES!
Source: by muscularmustangs.com
Self Test - & DTCs 3 digits & some Possible Causes, MANY CODES!
Source: by muscularmustangs.com
Self Test - Clearing Keep Alive Memory: "...To clear the KAM, disconnect the battery negative terminal for five minutes or more (preferably 15 minutes). Adaptive Strategy Relearn Procedure: After repairs have been made and the KAM cleared drive the vehicle for at least ten miles to allow the PCM to relearn the values for optimum performance. Note: During the ten mile relearn drive, the vehicle may exhibit some driveability symptoms. These should be eliminated when the KAM has relearned the operating values..."
Source: by Ford via miesk5 at Ford Bronco Zone Forums
Self Test - Continuous Memory Codes; These codes are retained in memory for 80 warm-up cycles. To clear the codes for the purposes of testing or confirming repair, perform the KOEO test. When the fault codes begin to be displayed, de-activate the test by either disconnecting the jumper wire (meter, MIL or message center) or releasing the test button on the hand scanner. Stopping the test during code transmission will erase the Continuous Memory. Do not disconnect the negative battery cable to clear these codes; the Keep Alive memory will be cleared and a new code, 19, will be stored for loss of PCM power..." (under license from Delmar Publishers, comb of Chilton/Nichols/Delmar & Haynes); some may be incorrect, as reported by Seabronc, thanks Seabronc! NEW SITE URL!!! MUST REGISTER TO VIEW; select year, make, model, engine size and go to appropriate section
Source: by Chilton via Autozone
Self Test - Diagnostic Trouble Codes (DTCs) NO CODES Troubleshooting; "...The self-test plugs were mounted on the passenger side fender on 1985-86 EFI trucks; The self-test plugs are located along the driver's side fender behind the air filter box on 87-95 EFI trucks..."; miesk5 NOTE; Self-Test Input (STI) is the Pin in the Lt gray Connector and Signal Return Ground (STO/SIGRET) is Pin E in black Connector in 87-95; The engine temperature must be greater than 50°F (10°C) to pass the KOEO Self-Test and greater than 180°F (82°C) to pass the KOER Self-Test. Run it around to heat the engine up and shift thru all gears incl Reverse. Then turn off all accesories/lights, etc. Make sure A/C is off and transmission is in Park (automatic) or in Neutral for a Manual & release clutch. Do Key On Engine Off (KOEO) portion first. Fix any codes from the KOEO test before you do the running test (KOER, key on, engine running). Look Codes up in my broncolinks.com site using the new Search function. Hardware Limited Operation Strategy (HLOS) Overview; "...HLOS mode is used when the system fault(s) is too extreme for the FMEM mode to handle. In HLOS mode, all software operations have stopped and the computer is running on hardware control only. The default strategy for this mode has a minimal calibration just to allow the vehicle to operate until it can be serviced. NOTE: IN HLOS MODE YOU WILL NOT GET ERROR CODES. The MIL light is turned on as a bulb check when the ignition key is first turned "ON". The EEC IV computer turns off the bulb as soon as it receives the PIP (crank) signal. If the light stays on during cranking, the computer is not receiving the PIP signal..."
Source: by Ryan M (Fireguy50) at fordfuelinjection.com
Self Test - Dynamic Response Test during a KOER Self-Test (also called a GOOSE Test/CODE); "...After many tests the computer will flash once, indicating a Dynamic Response test. This single flash is prompting you briefly push the gas pedal all the way down (do not over rev the engine)..."
Source: by Ryan M (Fireguy50) at fordfuelinjection.com
Self Test - ENGINE ID - "...The engine ID in a running test is a series of pulses equal to one half the number of engine cylinders. A 4 cylinder engine ID is 2 pulses, a 6 cylinder ID is 3 pulses and an 8 cylinder ID is 4 pulses. A diesel ID is 5..."
Source: by muscularmustangs.com
Self Test - Erasing Codes; Codes automatically erase after 60-100 starts. Starting the memory test procedure, and unplugging the connections erases memory codes. Disconnecting the battery will also erase all the codes; however, this may trigger a code 19 (loss of PCM power).
Source: by broncoii.org
Self Test - GOOSE CODE - KEY ON ENGINE RUNNING (KOER) TEST; A "GOOSE" code (also called a dynamic response test) is output during an engine running test. This is a single pulse to signal you to quickly move the throttle approximately 1/2 way down and release. NOTE: Not all engines give a "GOOSE" code.
Source: Zen (Alex) at zenseeker.net
Self Test - Keep Alive Memory (KAM) "...within the processor must always have voltage supplied to it. This voltage is supplied by the Keep Alive Power (KAPWR) circuit (Pin 1) that connects directly to the battery. KAM contains adaptive parameter tables that allow the processor to adapt to different operating requirements. It also contains the Continuous Memory codes. Continuous Memory codes will be erased any time KAPWR is disconnected (i.e. battery disconnected, processor disconnected, breakout box installed, open in the wire, etc.). If KAM fails within the processor, all Continuous codes will also be erased. Powertrain Control Module KAM Test Error Indicates the PCM has experienced an internal memory fault. However there are external items that can cause this DTC. Reprogramming Battery terminal corrosion KAPWR to PCM interrupt/open Loose battery connection Damaged PCM (less likely) ...basically, if the truck is running fine, don't worry. Now, in my 96 and in many Ford vehicles, a Code Reader Will NOT Power up; 96 Bronco & all Ford; Check the fuse for the cigarette lighter. It is shared with the OBDII connector power and is commonly blown due to bad wire routing around ash tray framework by Ford! or by shorted/high amp draw by Lighter element..."
Source: by miesk5 at Ford Bronco Zone Forums
Self Test - Keep Alive Memory (KAM) "...within the processor must always have voltage supplied to it. This voltage is supplied by the Keep Alive Power (KAPWR) circuit (Pin 1) that connects directly to the battery. KAM contains adaptive parameter tables that allow the processor to adapt to different operating requirements. It also contains the Continuous Memory codes. Continuous Memory codes will be erased any time KAPWR is disconnected (i.e. battery disconnected, processor disconnected, breakout box installed, open in the wire, etc.). If KAM fails within the processor, all Continuous codes will also be erased..."
Source: by Ford via miesk5 at cc
Self Test - Keep Alive Memory (KAM); "...contains the adaptive factors used by the processor to compensate for component tolerances and wear. It should not be routinely cleared during diagnosis. If an emissions related part is replaced during repair, the KAM must be cleared. Failure to clear the KAM may cause severe driveability problems since the correction factor for the old component will be applied to the new component..." (under license from Delmar Publishers, comb of Chilton/Nichols/Delmar & Haynes); some may be incorrect, as reported by Seabronc, thanks Seabronc! NEW SITE URL!!! MUST REGISTER TO VIEW; select year, make, model, engine size and go to appropriate section
Source: by Chilton via Autozone
Self Test - Keep Alive Memory (KAM); DO NOT DISCONNECT THE BATTERY. IT WILL ERASE KEEP ALIVE MEMORY AND RESET LONG TERM FUEL TRIM AND BARO TO THEIR STARTING/BASE VALUES
Source: by Ford via miesk5 at cc
Self Test - Scan Tool Won’t Initiate Self-Test Due to Poor Grounds, Corroded Wiring, etc.; read more on how to Ground the STI & Proceed w/ Test
Source: by Jeremy M (Big '92, jermil01) at SuperMotors.net
Self Test - Scan Tool Won’t Initiate Self-Tests Troubleshooting in EEC-IV; SIG-RTN, Self-Test Output circuit, etc.
Source: by Ryan M (Fireguy50) at fordfuelinjection.com
Self Test - Scan Tool Won’t Initiate Self-Tests; Vehicle Battery goes Dead, Short Solenoid Body Life, 4th Gear Starts in D/High Pressure may be caused by a malfunctioning Electronic Engine Control (EEC) Relay. The EEC relay is controlled by 12 volts from the ignition switch and is responsible for supplying voltage to the computer and solenoid body. If the relay contacts stick open, the complaints are as follows: Gas engine applications won’t start, Diesel will start and run, but have 4th gear starts in D, 2nd gear in 2 and 1, and maximum line pressure. If the contacts are stuck closed, the complaints may be as follows: Both gas and diesel engine application: Scan tool won’t work, vehicle battery goes dead, short solenoid body life. Note: Watch for corroded relay terminals and connectors on 89-91 E-series vans. The relay is very close to the right side battery and prone to corrosion problems especially on diesel ambulances..." read more, Diagrams are gone
Source: by ATC-Distribution Group Inc. atcdg.com via web.archive.org
Self Test - Video, Bronco & Ford; using a multimeter; miesk5 NOTE; Self-Test Input (STI) is the Pin in the Lt gray Connector and Signal Return Ground (STO/SIGRET) is Pin E in black Connector in 87-95; The engine temperature must be greater than 50°F (10°C) to pass the KOEO Self-Test and greater than 180°F (82°C) to pass the KOER Self-Test. Run it around to heat the engine up and shift thru all gears incl Reverse. Then turn off all accesories/lights, etc. Make sure A/C is off and transmission is in Park (automatic) or in Neutral for a Manual & release clutch. Do Key On Engine Off (KOEO) portion first. Fix any codes from the KOEO test before you do the running test (KOER, key on, engine running). Look Codes up in my broncolinks.com site using the new Search function.
Source: by broncodriver.com
Self Test - WIGGLE TEST; "...Engine running or engine off tests; Hook up for a self test but do not hook up the self test trigger. Turn key to on. Hook up the trigger, wait 10 seconds and disconnect. Hook up trigger again . Tap suspected sensors (be careful if engine is running), wiggle the wiring harnesses etc. IF the PCM picks up a fault the self test output will pulse and a memory code will be stored..."
Source: by muscularmustangs.com
Self Test Connector Location Diagram, Engine Area in a 91 4.9
Source: by Ford via chiltonlibrary.com
Self Test Connector Pin-Out Diagrams & Color Codes
Source: by miesk5 at FSB
Self Test Connector Wiring Diagram in a 92
Source: by Jeremy M (Big '92, jermil01) at SuperMotors.net
Self Test Connector Wiring Diagram in an 84
Source: by toddcomputer.com
Shudders, Bogs, & Intermittent No-Spark: Spark w/SPOUT Connector Un-Plugged, but No-Spark w/SPOUT Connected, due to distributor, in a 93 & KOER test won't begin; "...The engine starts to bogg down and then it shudders before it downshifts and smooths out. (example, when rpm’s drop going up an incline it will shudder for a few seconds before the rpm’s increase and it drops out of OD). If I remove the SPOUT the shuddering downshift problems goes away; then, when I replace the SPOUT the shuddering downshift problems comes back; Distributor was causing the problem..."
Source: by buck45 at Ford Bronco Zone Forums
Spark Timing & EGR Flow in Section 8, Page 161 of Ford Fuel Injection and Electronic Engine Control: How to Understand, Service and Modify, 1988-1993
Source: by Charles O. Probst via miesk5 at FSB
Strategies "...Start / Crank, Cold Start & Warm Up, Cold Drive-Away, Warm Idle, Warm Cruise, Full-Throttle Acceleration, Deceleration; Failure Mode & Adaptive Strategy
Source: by Ryan M (Fireguy50) at fordfuelinjection.com
Symbols in Wiring Diagrams
Source: by Steve83 (Steve, That dirty old truck) at SuperMotors.net
Testing, Overview & Diagrams, Thick Film Ignition (TFI), Distributor Mounted Ignition Control Module (ICM); "...Part I; In This Fast Test you'll be able to pinpoint the problem to the Ignition Control Module or the Ignition Coil or the Profile Ignition Pickup Sensor (PIP Sensor) in four easy test steps. This test will only help you in a Cranks but Does Not Start Condition. So then, before starting the tests, it's critical that you have checked and verified that there's NO SPARK present at the Ignition Coil. Why? Well, because if the Ignition Coil is sparking, it would be a clear indication that it and the Ignition Coil and the Crankshaft Position Sensor (PIP Sensor) are working. This article applies to both the Gray colored Ignition Control Module and the Black colored Ignition Control Module. The Gray colored Ignition Control Module is called the Push Start Module and the Black colored Ignition Control Module is called the Computer Controlled Dwell Module. These ignition control modules are not interchangeable. If you need the tests for the Ford Fender Mounted Ignition Control Module (ICM), click here. How Does the Ignition Control Module Work? Here's a little background information to help you diagnose this no spark condition. In a nutshell, when the system is working properly, at CRANK-UP and at all engine speeds, the Ignition Control Module controls the Ignition Coil. How? This is primarily done thru' the Profile Ignition Pickup Sensor Signal which is received by the Ignition Control Module (and also the ECM). The Ignition Control Module (ICM) upon receiving this signal, starts switching the Ignition Coil's Ground On and Off. As you may already know, it's this action that makes the Ignition Coil spark away. The Profile Ignition Pickup Sensor signal (more commonly called the PIP Signal) is critical for the Ignition Control Module to start sparking the Ignition Coil at START UP and at all engine speeds. The Profile Ignition Pickup Sensor is a Hall Effect type Crankshaft Position Sensor and produces a digital (On/Off) signal that can be seen with an LED or an oscilloscope. On an oscilloscope, it produces a digital square waveform. This sensor is located in the Distributor. What Tools do I Need for the Ignition Module Test? There are several ways to test this Ignition Control Module. An oscilloscope is the best way to check all of the input and output signals but it's not the only way. I'll show you just how. Anyway, if you have access to an oscilloscope, I have included photos of what the waveforms should look like. Whether you use a multimeter or an Oscilloscope, you'll be able to successfully diagnose this NO START CONDITION! So, here's the basic list: An LED Light. Test Light. Multimeter. A cheapie one will do. Repair Manual. For whatever other information this article does not cover. Helper. To help you crank the engine while you observe the LED light (or Test Light or Multimeter). By the way, you don't need an Automotive Scan Tool for any of these tests. We'll first check for the basics like Battery voltage and Engine Ground to the Ignition Control Module. Then we'll test the Ignition Coil Switching Signal that the Module generates in action and from the results you get you'll be able to pinpoint the problem to the Ignition Control Module (ICM) or the Ignition Coil or the Profile Ignition Pickup (PIP) Sensor or completely eliminate these as the cause of the No Start Condition. IMPORTANT- All of the tests are ON CAR TESTS, do not remove the Ignition Control Module Assembly from the vehicle (all of the figures show the Module Assembly off of the vehicle but this is just for illustration purposes only). Also, the Battery must be in a fully charged condition for all tests in this article. And lastly, this Fast Test only tests for a NO SPARK / No Start Condition. TEST INFO Circuit Descriptions; Here are brief descriptions of the circuits that we'll be testing. You'll notice that there are no wire color descriptions. This is intentional. The color of the wires in the illustration will not match the ones on your vehicle. The good news is that no matter what color the wires are (on the vehicle), the circuit descriptions DO NOT CHANGE. You will be able to successfully diagnose this NO START CONDITION with this information. IMPORTANT- It will be necessary to test some of these circuits while the engine is being cranked. Be careful, use common sense and take all necessary safety precautions. Ignition Control Module Connector; 1- Profile Ignition Pickup (PIP) Signal. 2- Spout. 3- 12 V at START. 4- 12 Volts (gray module) or IDM circuit (black module). 5- Ignition Coil Control Signal. 6- Ground. TEST 1 Checking for Power (12 V); We'll begin by checking that the Ignition Control Module is receiving 12 volts. I recommend using a wire piercing probe to accomplish all of the tests in this article. (click here to see a picture of this tool). Whatever method you use, the key here is to be careful. Remember to use common sense and take all safety precautions . IMPORTANT- The Ignition Coil, Ignition Control Module and the PIP Sensor receive 12 Volts from the same circuit. So if you test one, you test the others. 1 Put the multimeter in VOLTS DC mode. 2 It's not necessary to disconnect the Ignition Control Module (ICM). You'll probe the number 4 circuit of the Ignition Control Module Connector. 3 With the RED multimeter test lead and a suitable tool, probe the number 4 circuit wire of the Connector. 4 With the BLACK lead of the multimeter probe the BATT (-) NEGATIVE terminal. 5 Turn Key On with the Engine Off. Your Multimeter should register 12 Volts DC. CASE 1 If the Multimeter registered 12 Volts DC, All is good in the neighborhood, GO TO TEST 2. CASE 2 If the Multimeter DID NOT register 12 Volts DC, You must find out why you're missing this voltage. Without this voltage the Module, Ignition Coil, and the PIP Sensor will not work. TEST 2 Testing the Ground Circuit; Here we'll check that the Ignition Control Module (ICM) is receiving a good GROUND. This is done thru' the number 6 circuit of the Igntion Module Connector. 1 Put the multimeter in VOLTS DC mode. 2. With the BLACK multimeter test lead and a wire piercing probe, probe the Ignition Module Connector's number 6 circuit wire. 3 With the RED lead of the multimeter probe the BATT (+) POSITIVE terminal. Your Multimeter should register 12 Volts DC. CASE 1 If the Multimeter registered 12 Volts DC, All is good in the neighborhood, GO TO TEST 3. CASE 2 If the Multimeter DID NOT register 12 Volts DC, This means there is open in this circuit. Without this ground the Ignition Module will not function. Repair the circuit. EST 3 Ignition Coil Switching Signal; Now that you have verified the basics, in this test you're gonna' verify that the Ignition Control Module (ICM) is activating the Ignition Coil. Here you're going to use an LED test tool. Click here for a picture of this tool and how to make it. You can also use a Test Light for this test. Use an appropriate tool to pierce the wire and attach the LED test tool (to this tool). Be careful and use all necessary precautions. By the way, in case you want to see a more specific Ford Ignition Coil test, I’ve written one for troubleshootmyvehicle.com and you can see it here: Ford Ignition Coil Test. 1 Connect the RED wire of the LED to the Battery Positive Terminal. 2 Connect the BLACK wire of the LED to the number 5 circuit of the Ignition Control Module Connector 3 Have an assistant crank the engine. the LED test tool (or Test Light) should blink on and off as the engine is being cranked. Did this occur? CASE 1 The LED Light blinked On and Off as the engine was cranking, This means that the Ignition Control Module is triggering the Ignition Coil. So then, the Ignition Control Module is good and can been eliminated as the cause of the NO START condition. By a process of elimination, we can assume that the Ignition Coil is faulty and is the source of the NO START condition. Replace the Ignition Coil. CASE 2 The LED Light DID NOT blink On and Off as the engine was cranking, Re-check all of your connections and retry the test again. If still no light pulses on the test LED, GO TO TEST 4. TEST 4 Testing the PIP Signal; Here we'll check that the Profile Ignition Pickup Sensor (PIP) is being received by the Ignition Control Module (ICM). The PIP Signal is just Ford’s name for the Crankshaft Position Sensor Signal. Now, in case you’re wondering... the PIP Sensor is located inside the Distributor. This will be achieved by using the same LED test tool. Click here for a picture of this LED tool and how to make it. Do not use a Test Light for this test; With a suitable tool and with the key in the Off position, pierce the number 1 circuit wire of the Ignition Control Module Connector. Connect the BLACK wire of LED to the tool that is piercing the wire. Connect the RED wire of the LED to the BATTERY (+) POSITIVE terminal. Have an assistant crank the engine while you observe the LED. The LED should start to blink on and off as the engine is cranked. Is the LED blinking on and off as the engine is cranked? CASE 1 If the LED blinked On and OFF as your helper cranked the engine The Ignition Control Module (ICM) is BAD. Replace the Ignition Control Module. Here’s why: As you’re already aware, the Ignition Control Module needs: 1.) power in the form of 12 Volts. 2.) It needs a good path to ground. 3.) It needs the PIP Signal to start creating the Switching Signal the Ignition Coil needs to start sparking.. So, up until this point (in the testing) you have verified that the module does have power, that it does have ground and that it’s not creating a Switching Signal for the Ignition Coil. In this step you have confirmed that the PIP Sensor is generating a PIP Signal (as indicated by a blinking LED light). So, if the Ign. Module is getting power, ground and the PIP Signal (as evidenced by the blinking LED) is has to create a Switching Signal... if it doesn’t, it’s fried. CASE 2 The LED DID NOT blink On and OFF as your helper cranked the engine If you have no pulses, recheck all connections. Try again. If you still have no pulses. The Profile Ignition Pickup Sensor (PIP) is BAD and the cause of this NO START condition. You’ll need to replace the PIP Sensor to solve the No Start No Spark Condition on your Ford (or Mercury or Lincoln) vehicle. As mentioned earlier, the Profile Ignition Pickup (PIP) Sensor is just a Crankshaft Position Sensor located inside the Distributor. This is the Sensor that tells the Ignition Control Module (ICM) when to start activating the Ignition Coil to start Sparking away. So, if this PIP Signal is missing (as indicated by the LED not blinking on and off), the Ignition Control Module will not function..." SEE Site for Diagrams
Source: by easyautodiagnostics.com
The Parameter Identification (PID) mode allows access to powertrain control module (PCM) information. This includes analog and digital signal inputs and outputs along with calculated values and system status. There are two types of PID lists available and both are used throughout this manual. The first is the Generic (J1979) OBDII PID list. This is a standard set of PIDs for all manufacturers all scan tools must be able to access. The second is a Ford specific (J2190) list which can be accessed by an adequate scan tool. When accessing any of these PIDs, the values will be continuously updated. The Generic or Ford PID list provides definitions and values in appropriate units. For more information, refer to the Society of Automotive Engineers (SAE) J2205 document. Read More
Source: by miesk5 at FSB
Waterproofing the EEC Discussion
Source: by members at FSB
Waveforms, PIP, SPOUT, IDM in Push Start & CCD, Page 122 in Ford Fuel Injection and Electronic Engine Control: How to Understand, Service and Modify, 1988-1993; Scroll Down on First Page, Click on each Section, then on next page, click on the pdf file; the complete book is over 85MB pdf and can be downloaded @ http://www.yunost.ru/docs/Ford-injectors-book/Book.pdf
Source: by Charles O. Probst via yunost.ru
Wiring Diagram for 84 Bronco & F-Series (partial); "...Similar to 80-91 Bronco & F-Series..."
Source: by Steve83 (Steve, That dirty old truck) at SuperMotors.net
Wiring Diagram in an 86 (see page 2)
Source: by Xris at SuperMotors.net
Wiring Diagram in an 87
Source: by Yardape (Mavman, Yard Ape) at broncozone.com
Wiring Diagrams (Partial, Bronco similar) for F 150 in 86, 89, 91 & 95; EEC, Start/Ignition, EFI/Fuel System, Emissions, E4OD, AOD/C6 (+ clutch interlock switch), etc. from Electrical & Vacuum Troubleshooting Manual (EVTM)
Source: by Ford via Ryan M (Fireguy50) at fordfuelinjection.com
Wiring Harness Conversion for a 1992 EFI 4.9 Installation in an 83 (also, scroll to many sub-topics on his swap)
Source: by Michael C (collinsperformance, The Money Monster) at SuperMotors.net