P1646-HYDRAULIC COOLING FAN CONTROL CIRCUIT LOW
For a complete wiring diagram Refer to Section 8W.
- When Monitored:
Ignition on and engine running.
- Set Condition:
An open or shorted condition in the Hydraulic Fan Solenoid Control circuit is detected by the Front Control Module.
| Possible Causes |
| (A916) FUSED B+ CIRCUIT |
| (K173) HYDRAULIC RADIATOR FAN SOLENOID CONTROL CIRCUIT OPEN |
| (K173) HYDRAULIC RADIATOR FAN SOLENOID CONTROL CIRCUIT SHORTED GROUND |
| INTEGRATED POWER MODULE |
| FRONT CONTROL MODULE |
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING) .
Diagnostic Test
1. HYRDRAULIC COOLING FAN OPERATIONIgnition on, engine not running.
Using the scan tool, perform the Hydraulic Fan Solenoid Test.
Does the Hydraulic Cooling Fan operate properly?
Yes
- Refer to the INTERMITTENT CONDITION Diagnostic Procedure.
No
- Go To 2
2. (A916) FUSED B+ CIRCUIT CHECK
Turn the ignition off.
Disconnect the Hydraulic Cooling Fan Module harness connector.
Using a 12-volt test light connected to ground, probe the (A916) Fused B+ circuit in the Hydraulic Cooling Fan Module harness connector.
Does the test light illuminate brightly?
Yes
- Go To 3
No
- Repair the open or short to ground in the (A916) Fused B+ circuit
- Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)
3. (K173) HYDRAULIC RADIATOR FAN SOLENOID CONTROL CIRCUIT OPEN BETWEEN THE FAN AND IPM C2 HARNESS CONNECTOR
Disconnect the IPM C2 40 way connector.
Measure the resistance of the (K173) Hydraulic Radiator Fan Solenoid control circuit from Fan Module harness connector to the IPM C2 40 way harness connector.
Is the resistance below 5.0 ohms?
Yes
- Go To 4
No
- Repair the excessive resistance in the (K173) Hydraulic Radiator Fan Solenoid Control circuit.
- Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)
4. (K173) HYDRAULIC RADIATOR FAN SOLENOID CONTROL CIRCUIT SHORTED TO GROUND BETWEEN THE FAN AND IPM C2 HARNESS CONNECTOR
Measure the resistance between ground and the (K173) Hydraulic Radiator Fan Solenoid Control circuit in the Fan Module harness connector.
Is the resistance below 100 ohms?
Yes
- Repair the short to ground in the (K173) Hydraulic Radiator Fan Solenoid Control circuit.
- Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)
No
- Go To 5
5. (K173) HYDRAULIC RADIATOR FAN SOLENOID CONTROL CIRCUIT OPEN BETWEEN THE FAN AND IPM FCM 49 WAY HARNESS CONNECTOR
Connect the IPM C2 40 way connector.
Disconnect the IPM FCM 49 way harness connector.
Measure the resistance of the (K173) Hydraulic Radiator Fan Solenoid control circuit from Fan Module harness connector to the IPM FCM 49 way harness connector.
Is the resistance below 5.0 ohms?
Yes
- Go To 6
No
- Repair the excessive resistance in the (K173) Hydraulic Radiator Fan Solenoid Control circuit in the IPM.
- Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)
6. (K173) HYDRAULIC RADIATOR FAN SOLENOID CONTROL CIRCUIT SHORTED TO GROUND BETWEEN THE FAN AND IPM FCM 49 WAY HARNESS CONNECTOR
Measure the resistance between ground and the (K173) Hydraulic Radiator Fan Solenoid Control circuit in the Fan Module harness connector.
Is the resistance below 100 ohms?
Yes
- Repair the short to ground in the (K173) Hydraulic Radiator Fan Solenoid Control circuit in the IPM.
- Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)
No
- Go To 7
7. FRONT CONTROL MODULE
NOTE: Before continuing, check the FCM harness connector terminals for corrosion, damage, or terminal push out. Repair as necessary.
Using the schematics as a guide, inspect the wire harness and connectors. Pay particular attention to all Power and Ground circuits.
Were there any problems found?
Yes
- Repair as necessary.
- Perform BODY VERIFICATION TEST. (Refer to 8 - ELECTRICAL/ELECTRONIC CONTROL MODULES - STANDARD PROCEDURE)
No
- Replace and program the Front Control Module per Service Information.
- Perform BODY VERIFICATION TEST. (Refer to 8 - ELECTRICAL/ELECTRONIC CONTROL MODULES - STANDARD PROCEDURE)