P0480

P0480-FAN CLUTCH

P0480 - Fan Clutch:

WHEN MONITORED
When the ignition is on.

SET CONDITION
The PWM signal to the fan clutch does not match the PWM signal from the fan clutch.

POSSIBLE CAUSES
- Fan clutch
- Wire harness damaged
- Open fan clutch (K160) driver circuit
- (K160) Driver circuit shorted to (K690) return circuit
- (K160) Driver circuit shorted to battery negative
- Intermittent condition
- ECM

Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding.

Diagnostic Test

1. FAN CLUTCH





Disconnect the fan clutch harness connector.
Check connectors - Clean/repair as necessary.
Measure the resistance between the fan clutch (K160) driver circuit and the fan speed (K690) sensor return circuit on the fan clutch assembly.

Q: Is the resistance less than 10 Ohms?

YES: Replace the fan clutch. Perform the POWERTRAIN VERIFICATION TEST VER - 1 (DIESEL). Powertrain Verification Test - Ver 1
NO: Go To 2

2. FAN CLUTCH





Disconnect the Fan Clutch harness connectors.

NOTE: Check connectors - Clean/repair as necessary.

Measure the resistance between the fan clutch (K160) driver circuit and the fan clutch (F504) battery supply circuit on the fan clutch assembly.

Q: Is the resistance less than 6 Ohms or greater than 10 Ohms?

YES: Replace the fan clutch. Perform the POWERTRAIN VERIFICATION TEST VER - 1 (DIESEL). Powertrain Verification Test - Ver 1
NO: Go To 3

3. OPEN FAN CLUTCH (K160) DRIVER CIRCUIT





Disconnect the ECM harness connectors.
Check connectors - Clean/repair as necessary.
Measure the resistance of the fan clutch (K160) driver circuit between the ECM harness connector and the fan clutch harness connector.

Q: Is the resistance less than 10 Ohms?

YES: Go To 4
NO: Repair the open fan clutch (K160) river circuit. Perform the POWERTRAIN VERIFICATION TEST VER - 1 (DIESEL). Powertrain Verification Test - Ver 1

4. (K160) DRIVER CIRCUIT SHORTED TO (K690) RETURN CIRCUIT





Measure the resistance between the fan clutch (K160) driver circuit and the fan speed sensor (K690) return circuit at the sensor harness connector.

Q: Is the resistance greater than 100K Ohms?

YES: Go To 5
NO: Repair the (K160) Driver circuit shorted to (K690) Return circuit. Perform the POWERTRAIN VERIFICATION TEST VER - 1 (DIESEL). Powertrain Verification Test - Ver 1

5. (K160) DRIVER CIRCUIT SHORTED TO BATTERY NEGATIVE





Measure the resistance between the fan clutch (K160) driver circuit and the battery negative.

Q: Is the resistance greater than 100k Ohms?

YES: Go To 6
NO: Repair the (K160) Driver circuit shorted to battery negative. Perform the POWERTRAIN VERIFICATION TEST VER - 1 (DIESEL). Powertrain Verification Test - Ver 1

6. ECM





Reconnect the ECM harness connectors.
Measure the resistance of the fan clutch (K160) driver circuit between the fan clutch connector and battery negative.

Q: Is the resistance greater than 100k Ohms?

YES: Refer to the INTERMITTENT CONDITION Symptom (Diagnostic Procedure).
NO: replace the ECM. Perform the POWERTRAIN VERIFICATION TEST VER - 1 (DIESEL). Powertrain Verification Test - Ver 1