What fuse powers the A/C clutch circuit in this diagram?

Fuse panel position 9, a 30A fuse that is hot in run (fuse panel details on pages 17 and 22), feeding circuit 181 (BR/O wire).

What wire colors are used for the A/C clutch cycling pressure switch circuits?

Circuit 348 is LG/P (light green/purple) into the clutch cycling pressure switch, and circuit 347 is BK/Y (black/yellow) out of it to the A/C clutch field coil. Ground is circuit 57 (BK).

What are the blower resistor terminal wire colors?

The legend shows circuit 752 Y/R, circuit 260 R/O, circuit 261 O/BK, and circuit 754 LG/W.

Does the diagram differ between diesel and gasoline engines?

Yes. Circuit 348 splits at C289 into separate DIESEL and GASOLINE branches, each with its own clutch cycling pressure switch (C291), diode, and A/C clutch field coil. The gasoline side also includes a thermal limiter and a 4.9L-only feed to the Electronic Engine Control (page 37).

Is there any condition required for the A/C clutch cycling pressure switch to close?

Yes: a note states the blower must be on for the switch to close, and refers to page 128 for switch terminal details.

Home/ Registry/ Ford/ Bronco/ 1987-1991/ 1988 Ford Bronco/ Photo supermotors.net/registry/media/1017245

Ford Bronco/F-Series A/C-Heater Electrical Wiring Diagram - Clutch Circuit

A/C-heater electrical wiring diagram showing blower resistor, clutch cycling pressure switch and color-coded wires

‹ ›

Reference · 1987-1991 BroncoAll 175 wiring diagrams

Ford Bronco/F-Series A/C-Heater Electrical Wiring Diagram - Clutch Circuit

Ford 3G Alternator Wiring Diagram - Mega Fuse, Charge Lamp & Wire Colors

1973-1974 Ford Point-Type Ignition System Circuit Diagram - Coil & Distributor

Ford 4-Terminal Starter Relay Wiring Diagram - S & I Terminals, Coil & Starter

Ford 4-Terminal Starter Solenoid Wiring Diagram - S & I Terminal Functions

KC Driving Lights & LED Light Bar Relay Wiring Diagram - Ford Bronco Aux Lights

Connector faces page 150-22 with C128 VIP self-test connector pinouts and warning chime module

1986-95 Ford V8 Truck Speed Density EEC-IV Pinout Wiring Diagram

1990 Ford Bronco Speed Control Wiring Diagram 31-2 - Cruise Servo & Amplifier

1990 Ford Bronco Speed Control Wiring Diagram 31-1 - Cruise Control Circuit

Ford EEC-IV Self-Test Connector Diagram - STO, STI, SIGRTN & Fuel Pump Pins

1995 Ford Bronco 5.0L Engine Controls Wiring Diagram - MAP, HO2S, PCM (24-6)

175wiring diagrams1987-1991 Ford Bronco More reference

Manual steps 34-36 for checking TPS reference voltage and resistance with highlighted ohm specs

Service procedure

Ford 5.0 Fox Mustang Short Belt Routing Diagram - 84.5" & 70.5" vs Stock

Schematic

Welder Input Data Plate - Serial JH229505, Stock 901782, 200/230/460V Specs

Spec plate

Ford 5.0L V8 PCV Valve & Hose Routing Diagram - 9A474, 6B890, 6A664

Exploded parts

Ford 5.0L/5.8L Air Throttle Body Assembly Diagram - Canister Purge Ports & TPS

Manual page

Brochure

Blueprint

'89 Ford vehicle emission control information label with EEC IV/EFI timing steps and vacuum hose routing

Vacuum routing

1990 Ford Bronco Fuse Panel Diagram: Fuse Positions, Amps & Circuits (11-2)

Fuse chart

Ford V8 Intake Manifold Bolt Tightening Sequence Diagram - Stud Locations

Torque spec

A/C-heater electrical wiring diagram showing the clutch cycling pressure switch, blower resistor and color-coded circuits.

Part of 1987-1991 Ford Bronco Wiring Diagrams

AI caption April 2014 · Photo 38 of 68

This is a scanned page from a Ford factory-style electrical/vacuum troubleshooting manual (EVTM) showing the A/C-Heater (Electrical) wiring diagram. It covers the A/C clutch circuit fed from fuse panel position 9 (30 amp, hot in run) through circuit 181 (BR/O wire) and splice S603 to the A/C ON indicator switch at connector C157. From there, circuit 348 (LG/P) splits into two branches at connector C289: a DIESEL branch and a GASOLINE branch (highlighted with a red box by the uploader). Each branch passes through a clutch cycling pressure switch (connector C291), then circuit 347 (BK/Y) to the A/C clutch field coil and a suppression diode, returning to ground on circuit 57 (BK) through splices S583/S584 (diesel) and S562/S563/S554 (gasoline). A note indicates a lead "TO ELECTRONIC ENGINE CONTROL PAGE 37" applies to the 4.9L engine only, and the gasoline side also shows a thermal limiter. Legend text identifies blower resistor terminal circuits 752 Y/R, 260 R/O, 261 O/BK, and 754 LG/W. A caution states the blower must be on for the switch to close, referencing page 128 for switch terminals. Connectors and splices shown include C151, C157, C158, C175, C289, C291, S562, S583, S584, S603, S805, and S814.

Is this accurate? Sign in to help verify it.

Frequently asked questions

What fuse powers the A/C clutch circuit in this diagram?: Fuse panel position 9, a 30A fuse that is hot in run (fuse panel details on pages 17 and 22), feeding circuit 181 (BR/O wire).
What wire colors are used for the A/C clutch cycling pressure switch circuits?: Circuit 348 is LG/P (light green/purple) into the clutch cycling pressure switch, and circuit 347 is BK/Y (black/yellow) out of it to the A/C clutch field coil. Ground is circuit 57 (BK).
What are the blower resistor terminal wire colors?: The legend shows circuit 752 Y/R, circuit 260 R/O, circuit 261 O/BK, and circuit 754 LG/W.
Does the diagram differ between diesel and gasoline engines?: Yes. Circuit 348 splits at C289 into separate DIESEL and GASOLINE branches, each with its own clutch cycling pressure switch (C291), diode, and A/C clutch field coil. The gasoline side also includes a thermal limiter and a 4.9L-only feed to the Electronic Engine Control (page 37).
Is there any condition required for the A/C clutch cycling pressure switch to close?: Yes: a note states the blower must be on for the switch to close, and refers to page 128 for switch terminal details.