BroncoLinks.Com Header Image
FORD BRONCO -> CLIMATE CONTROL; heater, AC, blower motor/resistor -> Heater & Hoses
WELCOME to MIESK5's BIG BRONCO LINKS - We now have over 26,000 LINKs!
This is a Ford Bronco, Truck & Van Technical & Parts LINKS site developed by the MIESK5 Family & is not affiliated with the Ford Motor Co. in any manner.
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
Select A Category:
Heater Core Failure, Repeated TSB 01-15-06 for 85-96
Heater Core Leak Test Procedure TSB 89-14-9 for 88-89 Bronco, Aerostar, Bronco II, Econoline, F-150, F-250, F-350, Ranger, etc.
Heater Core Replacement TSB 92-17-11 for 92 Bronco & F Series
Hoses
Insufficient Heat TSB 88-09-10 for 87-88 Bronco & F Series
Lack of Heat, Temperature Blend Door Cam Spring Does Not Blend Door to Seat Properly TSB 92-4-13 for Vehicles Built Prior to 11/11/91, 92 Bronco & F Series & F-47
Low or No Heat/Air Conditioning, High Effort to Turn Temperature Control Knob, Poor Temperature Modulation TSB 96-13-7 for 92-95 Bronco, F Series, F-47
Water Valve
Select A Link:
"...The heater hose connected to the intake manifold or t-stat outlet flows AWAY from the engine. The heater hose connected to the water pump flows TO the pump... In most engines, coolant ALWAYS flows thru the heater core circuit. The outlet for the heater core is beside the t'stat, so the t'stat can never restrict flow to the heater core. This serves 2 purposes: it allows an unrestricted failsafe coolant flow (although the heater core isn't nearly large enough to cool the engine if the radiator becomes restricted), and it allows the cabin to receive heat as soon as it becomes available, irrelevant of the radiator temperature, ambient temp, t'stat, fan, or clutch/relay. Even if the coolant level becomes critically low, the heater circuit will still generally have coolant in it since it takes less coolant to sustain flow within its smaller capacity. In some vehicles, a problem has been recognized in which high engine RPM during warmup can result in excessive pressure within the heater core, resulting in rupture. The fix is to retrofit a slight restriction (an orifice plate) into the circuit upstream of the heater core to limit the flow, and thereby, the pressure. Returning coolant is typically routed directly into the water pump. If the heater core fails, it is safe to loop a hose from the outlet directly back to the return indefinitely. It may also be beneficial to occasionally reverse the hoses at the heater core to keep it flushed out. The direction of flow in the heater core is irrelevant..."
Source: by Steve83 (Steve, That dirty old truck) at fourdoorbronco.com
Air Conditioning & Heater Vacuum Diagram in 92-96; "...'80-91 similar, except '87-early '88 w/factory air..."
Source: by Ford via Steve83 (Steve, That dirty old truck) at SuperMotors.net
Air Conditioning & Heater Vacuum Diagram in a 95
Source: by Chilton
Box Drain Clog causes a Wet Floor
Source: by Jim G at alldata.com
Box Replacement (w/dealer installed AC) in an 83
Source: by Michael C (collinsperformance, The Money Monster) at SuperMotors.net
Cable Routing Diagrams in a 78 w/Nomenclature; scroll through Indy's Diagrams to see more
Source: by Indybronco (Lula Mae) at SuperMotors.net
Chilton Manual for 66 - 81 Bronco, Scanned Copy
Source: by Chilton via broncocity.com
Climate Control System Wiring Diagrams in a 96; Heater, A/C & Heater Blower Motor Connector, Blower Motor Switch Resistor Connector, A/C-Heater Control Assembly Connector, A/C Cycling Switch Connector, A/C Pressure Cut-Off Switch Connector Pin-Out Diagrams from 1996 F-150, F-250, F-350, F-Super Duty and Bronco, F-Super Duty Motorhome Chassis Workshop Manual
Source: by Ford via thedieselstop.com
Control Assembly Connector Location, Behind Instrument Panel Diagram in a 96, Page 2
Source: by Ford via Chilton
Control Assembly Illumination Connector Location Behind Dash in a 90
Source: by Seattle FSB (SeattleFSB) at SuperMotors.net
Control Overview in 80-86; "Off- Vacuum is applied to da Outside Recirc Door Vac Motor, closing that door to outside Air. Normal A/C - Outside-Recirc Door is open to outside air. The panel door directs air to the instr panel registers. The Temperature Control Lever moves a cable connected to da Temp Blend Door that mixes heated & un-heated air In Defrost Mode; with No vacuum to any vacuum "motor" (cannisters looking thangs), air Flows to Defroster outlets (& air compr clutch is engergized) Vent - Outside-Recirc Door is open to outside air, as in Normal A/C. Vacuum is applied to the Panel Door Vacuum Motor, letting air flow only to the instr panel registers. In the same way, the defroster outlets are closed by the Floor/Defrost Vacuum Motor. Floor - The Outside-Recirc Door is Open to outside air. With No Vacuum at the Panel Door Vacuum Motor. The Panel Door directs air to the floor outlets. Mix - Vacuum is applied only to Port A of the Floor/Defrost Vacuum Motor positioning the Floor/Defrost Door at mid-position. Air Flow is split between the floor & windshield. There is no vac at the Panel Door Vacuum"
Source: by miesk5 at FSB
Control Panel Diagram in a 78
Source: by Indybronco (Lula Mae) at SuperMotors.net
Control Panel Diagrams & Overview in 92-96
Source: by Ford via Steve83 (Steve, That dirty old truck) at SuperMotors.net
Control Panel Illumination Connector Location, Behind Instrument Panel Diagram in a 96, Page 2
Source: by Ford via Chilton
Control pics in a 78
Source: by Indybronco (Lula Mae) at SuperMotors.net
Controls Overview in an 83 from Owner's Manual
Source: by Steve83 (Steve, That dirty old truck) at SuperMotors.net
Controls Overview in an 86 from Owner's Manual
Source: by Steve83 (Steve, That dirty old truck) at SuperMotors.net
Core & Box Swap pics in a 78
Source: by Tony E (shadowcaster II) at SuperMotors.net
Core & Motor Replacement in 73-79 F Series & 78-79 Bronco with Factory A/C or Hi/Lo Heaters
Source: by Trent (Picador, a Four Door 79, InfoFord) at ncspecialties.com
Core & Motor Replacement in 78-79 & 73-79 F Series
Source: by Ford via Broncobill78 (Dave) at Ford Bronco Zone Forums
Core Bypass Installation in an 88
Source: by 88rustsurvivor (monster) at FSB
Core Failure, Repeated Article about TSB 01-15-06 for 85-96
Source: by Ford via Gary G via Tomorrow's Technician, August 2006 via web.archive.org
Core Failure, Repeated TSB 01-15-06 for 85-96
Source: by Ford via miesk5 at miesk5's Home Page of Bronco Links
Core Location in Parts Break-Out Diagram in 80-86
Source: by Steve83 (Steve, That dirty old truck) at SuperMotors.net
Core Parts Break-Out Diagram in 80-96 w/ Nomenclature; Case is shown front-down
Source: by Steve83 (Steve, That dirty old truck) at SuperMotors.net
Core Replacement (w/AC) in an 86 5.0
Source: by Sixlitre (Malcolm H, Eddie Bauer) at SuperMotors.net
Core Replacement (w/AC) in an 86 5.0
Source: by Sixlitre (Malcolm H, Eddie Bauer) at FSB
Core Replacement in a 92
Source: by KGunner (poopy_pants) at FSB
Core Replacement in a 92
Source: by KGunner (poopy_pants) at SuperMotors.net
Core Replacement in a 93 F 250 (also for 87-92 Broncos & 87-96 F series)
Source: by rebelranger at FSB
Core Replacement in a 95
Source: by Ford via justanswer.com
Core Replacement in an 89 5.0
Source: by Brahma502 at SuperMotors.net
Core Replacement Info Video in an 86
Source: by JKossarides ("The Bronco", Jean) at SuperMotors.net
Core Replacement Instructions in a 92 (scroll)
Source: by 2carpros.com
Core Replacement Instructions in a 94; "...from Mitchell on Demand: Drain cooling system.Disconnect heater hoses. Remove glove box for access.Remove 7 screws attaching heater access to cover to plenum.Disconnect vacuum source. Leave harness attached to cover. Remove cover. Remove heater core from plenum. To instali, reverse removal procedure. Labor time 1.1 Hours Ford part # E9TZ 18476 B list $78.79..."
Source: by bnkrtstk (SOLD, Steve B, Camo Clunker) at FSB
Core Replacement pics in a 78
Source: by crawler (Andrew T, custom_78) at SuperMotors.net
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 Ford via Chris B (Blue, bronco boy) at telus.net
Engine Coolant Concerns TSB 93-24-08 for 84-94 Bronco, F Series, Aerostar, Econoline & many others; See table to check if Heater Core is Plugged; "...ISSUE: Engine performance concerns such as hesitation or stall, rough idle, and/or poor fuel economy may be caused by the thermostat stuck in an open position or opening at a temperature lower than specified. ACTION: Use the following "Cooling System Diagnosis" procedure to diagnose a cooling system that may not be reaching normal operating temperature. Follow the "Thermostat Diagnosis" procedure to determine if the thermostat may be at fault. Check the thermostat without removing it from the vehicle by using Rotunda Service Coolant Temperature Monitor Harness 007-00064. DIAGNOSIS PROCEDURE; A new cooling system diagnosis procedure has been developed for engines that do not reach normal operating temperature. A new thermostat diagnosis procedure also has been developed, using a new service coolant temperature monitor harness. See chart for proper diagnostic procedure. NOTE: THIS PROCEDURE WILL DIAGNOSE ONLY COOLING SYSTEMS THAT MAY NOT BE REACHING NORMAL OPERATING TEMPERATURE. IT WILL NOT DIAGNOSE A THERMOSTAT THAT CAUSES AN ENGINE OVERHEAT CONDITION. THERMOSTAT DIAGNOSIS; NOTE: DISCONNECTING THE POWERTRAIN CONTROL MODULE (PCM) TO ATTACH A BREAKOUT BOX OR AN EEC IV MONITOR WILL ERASE THE ADAPTIVE LEARNING FROM MEMORY AND MAY "HIDE" A DRIVE CONCERN TEMPORARILY UNTIL THE ADAPTIVE LEARNING IS RE-LEARNED. NOTE: THIS PROCEDURE IS MOST ACCURATE IF PERFORMED INDOORS AT LESS THAN 100°F (38°C) AMBIENT TEMPERATURE. THIS TEST MAY BE PERFORMED WITH OR WITHOUT THE HOOD OPEN AND WITH THE ENGINE WARM OR COLD. CAUTION: ALWAYS VENT THE EXHAUST TO THE OUTSIDE WHEN PERFORMING THIS TEST. 1. Check the coolant level in the radiator and coolant recovery reservoir. 2. With the key in the "off" position, proceed as follows: a. Remove the engine coolant temperature (ECT) sensor harness connector. b. Attach Rotunda Service Coolant Temperature Monitor Harness 007-00064 as a jumper between the PCM and the ECT. c. Attach Rotunda 73 Digital Multimeter 105-00051 or equivalent to the thermostat monitor harness. Voltage values (0-5vdc) may now be monitored while the sensor retains its connection to the wiring harness. NOTE: A ROTUNDA NEW GENERATION STAR TESTER (NGS) 007-00500 OR THE ROTUNDA SERVICE BAY DIAGNOSTIC SYSTEM (SBDS) 001-00001 MAY BE USED TO MONITOR THE ECT ON VEHICLES EQUIPPED WITH DATA COMMUNICATIONS LINK (DCL). THE SBDS SEQUENCE TO USE FOR THE SCREEN IS "TOOLBOX - ELECTRONIC ENGINE CONTROL AND DCL - ITEM". 3. Vehicles equipped with electric engine cooling fan(s) must have a fan running during this test (high or low speed may be used). Two methods may be used to turn the fan(s) on: a. Disconnect the A/C compressor clutch power supply and turn the climate control to A/C "ON". Or b. Disconnect the power supply to the cooling fan and supply 12 volts direct to the fan connector from the battery. NOTE: A GROUND MAY BE REQUIRED FOR SOME APPLICATIONS. 4. Place transmission in "park" or "neutral". NOTE: RUNNING THIS TEST WITH THE VEHICLE IN GEAR OR WITH THE A/C COMPRESSOR CLUTCH ENGAGED (RUNNING) WILL CAUSE IMPROPER DIAGNOSIS 5. Start the engine and allow to idle throughout this test: a. Allow engine to run for 2 minutes, then record ECT voltage. b. From now on, record ECT voltage every 60 seconds. c. When the ECT voltage trend changes direction or changes only slightly (0.03 volts or less) from the previous reading, record this as the thermostat opening voltage. d. Use the "Voltage and Corresponding Temperature Chart" shown below to obtain actual coolant temperatures. 6. If the opening voltage is GREATER than 0.75 volts (less than 180° F/ 82° C), or 0.85 volts (170° F/ 77° C) for 2.3L HSC engine only, replace the thermostat. Refer to the dealer Master Parts Catalog for correct thermostat usage. 7. If the thermostat opening voltage is LESS than 0.75 volts (greater than 180° F/ 82° C), or 0.85 volts (170° F/ 77° C) for 2.3L HSC engine only, the thermostat is good and should NOT be replaced. The "Cooling System Diagnosis Chart" should be referenced for further instructions. NOTE: The 10° F opening temperature difference for the 2.3L HSC engine is due to the ECT sensor location. OTHER APPLICABLE ARTICLES: NONE SUPERSEDES: 93-14-04 WARRANTY STATUS: INFORMATION ONLY..."
Source: by Ford via Steve83 (Steve, That dirty old truck) at SuperMotors.net
Fan Switch Connector, Burnt pic in an 88
Source: by Ironclad (Jeff J, da Money Pit) at SuperMotors.net
Fan Switch Replacement in 78-79 & 73-79 F Series
Source: by Ford via Broncobill78 (Dave) at Ford Bronco Zone Forums
Floor Panel Door, Temperature Blend Door (Cable Controlled), Floor & Defrost Door etc. Location w/Vacuum Line Colors in Parts Break-Out Diagram in a 96 from Workshop Manual
Source: by Ford via thedieselstop.com
Heater Core Leak Test Procedure TSB 89-14-9 for 88-89 Bronco, Aerostar, Bronco II, Econoline, F-150, F-250, F-350, Ranger, etc.
Source: by Ford via miesk5 at FSB
Heater Core Pic in 96 Bronco. Fits all '92-96 F-Series & Bronco
Source: by Steve83 (Steve, That dirty old truck) at SuperMotors.net
Heater in Center Console Info & pics in an 88
Source: by John G at fte
Heater Outlet Nipple Fabrication (from the t'stat cover to the heater core) in an 83
Source: by Steve83 (Steve, That dirty old truck) at SuperMotors.net
Heater, Auxiliary, JC Whitney Installation Info & pics in a 90
Source: by Chris S (Swat, Carcass, Blown, CLYDE) at FSB
Heater, Auxiliary, JC Whitney Installation pics in a 90
Source: by Chris S (Swat, Carcass, Blown, CLYDE) at SuperMotors.net
Leak Detection, General
Source: by aa1car.com
More Heat in a 90; "...So the '87-'91 trucks with factory A/C have a recirculation door in their HVAC system, it's there to cut off outside air and keep running only in-cab air through the blower. It's vacuum controlled, and only cuts outside air when you put the control lever to "off" or "max A/C". I found on FSB board that the problem with this is when you have -10 ambient temperature with some -20 windchill, heating up that air good could be a challenge for a truck with an aging heater core or tired blower fan. Just to see how much of difference it actually makes I zip-tied my recirculation door closed, thus running inside air through the HVAC system all winter long - things got real warm real quick, noticeable improvement even when truck is stationary. For the warmer days tho I want the recirculation door open so I can get fresh air in the cab as I drive... So I devised and implemented a solution in my '90 truck - I zip tied the vacum pot closed which means I can get tons of heat in the winter even with some -20 degree temperature sand summer time i can snip it off! the '92-'96 trucks utilize the same recirculation door setup as the '87-'91, so it should be possible to do this mod to one of these truck as well..."
Source: by 90bronco at Maritime Off-Road
More Heat; "...the 87-91 trucks with factory A/C have a recirculation door in their HVAC system, it's there to cut off outside air and keep running only in-cab air through the blower. It's vacuum controlled, and only cuts outside air when you put the control lever to off or max A/C. The problem I see with this is when you have 15F ambient temperature with some -20 windchill, heating up that air good could be a challenge for a truck with an aging heater core or tired blower fan. Last year just to see how much of difference it actually makes I zip-tied my recirculation door closed, thus running inside air through the HVAC system all winter long - things got real warm real quick, noticeable improvement even when truck is stationary. For the warmer days tho I want the recirculation door open so I can get fresh air in the cab as I drive... So I devised and implemented a solution in my 90 truck - I now have a manually controlled recirculation door that I can open and close to my liking, which means I can get tons of heat in the winter even with some nasty ambient temperatures..."
Source: by M.L.S.C. at FSB
Parts Break-Out Diagram in a 78 w/ out Nomenclature
Source: by broncohq.com
Parts Break-Out Diagram in a 78 without Nomenclature
Source: by Indybronco (Lula Mae) at SuperMotors.net
Repair Price Estimator, Bronco from 90-96 and other Fords; including labor & parts, shops in area, by Zip Code
Source: by RepairPal
Symbols in Wiring Diagrams
Source: by Steve83 (Steve, That dirty old truck) at SuperMotors.net
Temperature Door Location in Parts Break-Out Diagram in 80-86
Source: by Steve83 (Steve, That dirty old truck) at SuperMotors.net
Vacuum Hose Harness Pic in 80-96; "...80-96 similar, except 87-early 88 w/factory air; The 80-86 vacuum tank is a plastic ball on the R wheelwell..."
Source: by Steve83 (Steve, That dirty old truck) at SuperMotors.net
Vacuum Motor Locations in Parts Break-Out Diagram in 80-86
Source: by Steve83 (Steve, That dirty old truck) at SuperMotors.net
Vacuum Motor Replacement in a 90
Source: by 90bronco at Maritime Off-Road
Wiring Diagram in an 84 (diagram #3)
Source: by toddcomputer.com
Wiring Harness & Component Location Diagram, Ford Part Numbers, Depictions, etc. from Ford Workshop Manual in 96 Bronco, F-150, F-250, F-350, F-Super Duty Chassis Cab & Motorhome Chassis; use your Browser's SEARCH (or FIND) function to locate what you seek in each Diagram, such as Air Conditioning, Heater, Defroster Plenum and Duct, etc.
Source: by Ford via thedieselstop.com