A/C HIGH PRESSURE SENSOR (F65)
A/C High Pressure Sensor sends a digital signal to A/C Control Module. The A/C High Pressure Sensor needs to sense a pressure between 26 psi (1.8 bar) 464 psi (32 bar) for the A/C system to turn on. The Coolant Fan Control Module (J293) regulates coolant fan speed.
AFTER-RUN COOLANT PUMP
Note. Models with 4.2L V8 engines are not equipped with an After-Run Coolant Pump.
3.0L V6
Note. After Run Coolant Pump (V51) is operated by Coolant Fan Control Module. There is no diagnostic information available from the manufacturer for Coolant Fan Control Module.
Models with 3.0 V6 engine are equipped with an After Run Electric Coolant Pump (V51). After Run Electric Coolant Pump (V51) is actuated by the Coolant Circulation Pump Relay (J151). Coolant Circulation Pump Relay (J151) needs a ground signal from the ECM (J220) to accurate After Run Electric Coolant Pump (V51).
When engine is turned off and coolant temperature is above 195°F (91°C) After-Run Coolant Pump and Coolant Fan will be turned on. The After-Run Coolant Pump (V51) and 2nd speed Coolant Fan (V177) are generally activated for 3 to 10 minutes about 15 seconds after ignition is shut off.
COOLANT FAN CONTROL MODULE
Note. No diagnostic information is available from the manufacturer. Cooling Fan Control Module (J293) always has positive battery voltage (B+) and Cooling Fan(s) has a permanent ground.
Coolant Fan Control Module (J293) controls Coolant Fan and After-Run Coolant Pump (V51). Coolant Fan Control Module (J293) utilizes input from Coolant Fan Control Thermo Switch, A/C High Pressure Sensor (G65) and ECM (J220).
4.2L V8
Coolant Fan Control Module (J293) controls Coolant Fans No.1 (V7) and No. 2 (V177). Coolant Fan Control Module (J293) utilizes input from Coolant Fan Control Thermo Switch, A/C High Pressure Sensor (G65) and ECM (J220).
Coolant Fan Control Thermo Switch is a 2-stage thermo switch. At a preset temperature, (Coolant Fan Thermo Switch specific) Coolant Fan Thermo Switch completes a ground circuit to the Coolant Fan Control Module (J293). The first ground signal is to actuate Coolant Fan No.1 (V7). At a higher preset temperature Coolant Fan Thermo Switch completes a second ground circuit to the Coolant Fan Control Module (J293). The second ground signal is to actuate Coolant Fan No.2 (V177).
3.0L
Coolant Fan Control Thermo Switch is a 2-stage thermo switch. At a preset temperature, (Coolant Fan Thermo Switch specific) Coolant Fan Thermo Switch completes a ground circuit to the Coolant Fan Control Module (J293). The first ground signal is to actuate Coolant Fan 1st speed. At a higher preset temperature Coolant Fan Thermo Switch completes a second ground circuit to the Coolant Fan Control Module (J293). The second ground signal is to actuate Coolant Fan 2nd speed.
COMPONENT LOCATIONS
| Component | Location | |
|---|---|---|
| A/C High Pressure Sensor (F65) | ||
| 4.2L V8 | Right Front Corner Of Engine Compartment, Lower Left. (Scheme 1) | |
| 3.0L V6 | Right Front Corner Of Engine Compartment, Lower Left. (Scheme 2) | |
| After Run Coolant Pump | Under Vehicle, Behind Left Side Of Oil Pan. (Scheme 3) | |
| Climatronic (Auto A/C) Control Module (E87) | Integrated with A/C Control Panel | |
| Coolant Fan Control Module (J293) | ||
| 4.2L V8 | Front Of Engine Compartment, Lower Left. (Scheme 5) | |
| 3.0L V6 | Front Of Engine, By Cooling Fan. (Scheme 6) | |
| Coolant Fan Ground Point | Left Lower A Pillar | |
| Coolant Fan Thermo Switch | In Lower Right Corner In Radiator Hose/Tube Fitting Close To Radiator Tank. (Scheme 7) | |
| Eight-Fold Auxiliary Relay Panel | Under Left Side Of Dash, Behind Trim Panel. (Scheme 8) | |
| Fuse Locations | ||
| 3.0L V6 | Eight-Fold Auxiliary Relay Panel. (Scheme 8) (1) | |
| 4.2L V8 | Eight-Fold Auxiliary Relay Panel. (Scheme 8) (2) | |
| Passenger Compartment Fuse Panel | Behind Access Cover On Far Left End Of Dash. (Scheme 9) | |
| (1) Fuse locations on Eight Fold Relay Panel. For Coolant Fan Control Module (J293). Models with the 3.0L V6 engine; for MY 2002 fuse positions are No. 20 Coolant Fan (60A) and No. 21 (5A), for MYs 2003 and 2004 fuse positions are No. 19 Coolant Fan (60A) and No. 21 (5A). (2) Fuse locations on Eight Fold Relay Panel. For Coolant Fan Control Module (J293). Models with the 4.2L V8 engine; Power to Coolant Fan Control Module (J293) are fuse positions No. 20 Coolant Fan (60A) and No. 21 (5A) on Eight Fold Relay Panel. | ||
| (1) | Fuse locations on Eight Fold Relay Panel. For Coolant Fan Control Module (J293). Models with the 3.0L V6 engine; for MY 2002 fuse positions are No. 20 Coolant Fan (60A) and No. 21 (5A), for MYs 2003 and 2004 fuse positions are No. 19 Coolant Fan (60A) and No. 21 (5A). |
| (2) | Fuse locations on Eight Fold Relay Panel. For Coolant Fan Control Module (J293). Models with the 4.2L V8 engine; Power to Coolant Fan Control Module (J293) are fuse positions No. 20 Coolant Fan (60A) and No. 21 (5A) on Eight Fold Relay Panel. |
COMPONENT LOCATIONS
Scheme 1
Scheme 2
Scheme 3
Scheme 4
Scheme 5
Scheme 6
Scheme 7
Scheme 8
Scheme 9
SYSTEM TESTS
System testing information is not available from manufacturer. To assist in circuit diagnosis, see WIRING DIAGRAMS . Ensure all fuses are okay before proceeding with any testing. If a fuse is blown, check for a short circuit and repair before replacing fuse.
A/C HIGH PRESSURE SENSOR
The 3-wire sensor pin values are as follows
- Pin 1: Ground
- Pin 2: Duty Cycle signal to A/C Control Head (E87)
- Pin 3: Power when ignition is on (15+)
Duty cycle reading can be used to diagnose A/C high pressure sensor. Turn ignition on, with engine off. See A/C HIGH PRESSURE SENSOR SPECIFICATIONS table.
| Duty Cycle | Possible Cause | Corrective Action |
|---|---|---|
| 12 % to 87.5% | Sensor OK | None. Sensor reading is normal. |
| 88% | Faulty Sensor | Replace Sensor |
| 11% | Low Refrigerant | Recharge A/C System |
| 11% | Faulty Sensor | (1) Replace Sensor |
| (1) Ensure refrigerant system is fully charged before assuming sensor is faulty. | ||
| (1) | Ensure refrigerant system is fully charged before assuming sensor is faulty. |
A/C HIGH PRESSURE SENSOR SPECIFICATIONS
COOLANT FAN
Note. There are no Coolant Fan diagnostic information available from the manufacture for the 3.0L V6 engine.
3.0L V6 & 4.2L V8
Note. There is no diagnostic information available from the manufacturer for Coolant Fan(s), single coolant fan or No. 1 coolant fan (V7), No. 2 coolant fan (V177).
COOLANT FAN CONTROL THERMO SWITCH
Note. There are no Coolant Fan Control Thermo Switch specifications available from the manufacture for the 3.0L V6 and 4.2 L V8 engine. Temperature may be marked on side of switch, (on hexagon).
The 3.0L V6 does not have a Coolant Fan Control Thermo Switch. Coolant Fan Control Module (J293) receives a signal from ECM (J220) to turn on Coolant Fan (V7).
Note. There are no Coolant Fan Control Thermo Switch specifications available from the manufacture for the 3.0L V6 and 4.2 L V8 engine. Temperature may be marked on side of switch, (on hexagon).
If coolant Fan Control Thermo Switch is suspect, check wiring to Coolant Fan Control Thermo Switch open or short circuits. See WIRING DIAGRAMS . If wiring is okay, replace Coolant Fan Thermo Time Switch. If wiring is not okay, repair wiring as necessary.
The Coolant Fan Control Module controls the Coolant Fan(s) and the After-Run Coolant Pump. There is no diagnostic information available from the manufacturer for Coolant Fan Control Module.
Note. The Coolant Fan Control Module (J293) controls the Coolant Fan(s) and the After-Run Coolant Pump. There is no diagnostic information available from the manufacturer for After-Run Coolant Pump (V51).
TORQUE SPECIFICATIONS
| Application | Ft. Lbs. (N.m) |
|---|---|
| Coolant Fan Control Thermo Switch | 26 (35) |
| INCH Lbs. (N.m) | |
| A/C High Pressure Sensor | (1) 44 (5) |
| (1) A/C refrigerant does not need to be discharged. Use new "O" ring. | |
| (1) | A/C refrigerant does not need to be discharged. Use new "O" ring. |
TORQUE SPECIFICATIONS
2002
See 3.0L under COOLING FAN in SYSTEM WIRING DIAGRAMS in ELECTRICAL.
See 4.2L under COOLING FAN in SYSTEM WIRING DIAGRAMS in ELECTRICAL.
2003
See 3.0L under COOLING FAN in SYSTEM WIRING DIAGRAMS in ELECTRICAL.
See 4.2L under COOLING FAN in SYSTEM WIRING DIAGRAMS in ELECTRICAL.
2004
See 3.0L under COOLING SYSTEM in SYSTEM WIRING DIAGRAMS in ELECTRICAL.
See 4.2L under COOLING FAN in SYSTEM WIRING DIAGRAMS in ELECTRICAL.
See also:
• WIRING DIAGRAMS