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P1647

P1647-HYDRAULIC COOLING FAN CONTROL CIRCUIT HIGH

P1647-Hydraulic Cooling Fan Control Circuit High:






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
- (Z823) Ground circuit open
- (K173) Hydraulic radiator fan solenoid control circuit shorted to voltage
- Integrated power module
- Front control module

Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding.

Diagnostic Test

1. HYDRAULIC COOLING FAN OPERATION

Ignition on, engine not running.
Using the scan tool, perform the Hydraulic Fan Solenoid Test.

Q: Does the Hydraulic Cooling Fan operate properly?

YES: Refer to the INTERMITTENT CONDITION Diagnostic Procedure. Component Tests and General Diagnostics
NO: Go To 2




2. (Z823) GROUND CIRCUIT CHECK

Turn the ignition off.
Disconnect the Hydraulic Cooling Fan Module harness connector.
Using a 12-volt test light connected to B+, probe the (Z823) Ground circuit in the Hydraulic Cooling Fan Module harness connector.

Q: Does the test light illuminate brightly?

YES: Go To 3
NO: Repair the open in the (Z823) Ground circuit. Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test




3. (K173) HYDRAULIC RADIATOR FAN SOLENOID CONTROL CIRCUIT SHORTED TO VOLTAGE BETWEEN THE FAN AND IPM FCM 49 WAY HARNESS CONNECTOR

Disconnect the IPM FCM 49 way connector.
Ignition on, engine not running.
Measure the voltage on the (K173) Hydraulic Radiator Fan Solenoid control circuit at the Hydraulic Fan Module harness connector.

Q: Is the voltage above 0 volts?

YES: Go To 4
NO: Go To 5. Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test




4. (K173) HYDRAULIC RADIATOR FAN SOLENOID CONTROL CIRCUIT SHORTED TO VOLTAGE IN THE IPM

Turn the ignition off.
Disconnect the C2 IPM 40 way harness connector.
Ignition on, engine not running.
Measure the voltage on the (K173) Hydraulic Radiator Fan Solenoid control circuit at the Hydraulic Fan Module harness connector.

Q: Is the voltage above 0 volts?

YES: Repair the short to voltage in the (K173) Hydraulic Radiator Fan Solenoid control circuit between the Hydraulic Cooling Fan Module harness connector and the C2 IPM harness connector. Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test
NO: Replace the Integrated Power Module. Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test

5. 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.

Q: Were there any problems found?

YES: Repair as necessary. Perform BODY VERIFICATION TEST VER - 1. Body Verification Test
NO: Replace and program the Front Control Module. Perform BODY VERIFICATION TEST VER - 1. Body Verification Test