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P0480

P0480-COOLING FAN 1 CONTROL CIRCUIT

P0480-Cooling Fan 1 Control Circuit:






WHEN MONITORED
With the ignition on. Battery voltage greater than 10 volts.

SET CONDITION
An open or shorted circuit is detected in the radiator fan relay control circuit. One Trip Fault. Three good trips to turn off the MIL.

POSSIBLE CAUSES
- (A201) Fused (B+) feed circuits
- (N201) Radiator fan control relay control circuit open
- (N201) Radiator fan control relay circuit short to ground
- Radiator fan control relay
- Front control module

Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding.

Diagnostic Test

1. RADIATOR FAN CONTROL RELAY OPERATION

NOTE: When actuating the radiator fan relays, the Radiator Fan(s) may have a delay in operation and ramp up slowly.

Ignition on, engine not running.
With a scan tool, select Radiator Cooling Fan Relay #1 Control State to actuate the Radiator Fan Control Relay.

Q: Is the Cooling Fan Relay operating?

YES: Refer to the INTERMITTENT CONDITION Diagnostic Procedure. Intermittent Condition
Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test
NO: Go To 2




2. (A201) FUSED B+ CIRCUITS

Turn the ignition off.
Remove the Radiator Fan Control Relay.
Using a 12-volt test light connected to ground, probe the (A201) Fused B+ circuits.

Q: Is the voltage above 11.0 volts?

YES: Go To 3
NO: Repair the open or short to ground in the (A201) Fused B+ circuits. Inspect the related fuse and repair as necessary. Perform BODY VERIFICATION TEST VER - 1. Body Verification Test




3. RADIATOR FAN CONTROL RELAY CONTROL CIRCUIT

Turn the ignition on, engine not running.
With a scan tool, select Radiator Cooling Fan Relay #1 Control State, Toggle, to actuate the Radiator Fan Control Relay.
Using a 12-volt test light connected to battery voltage, probe the Radiator Control Relay Control circuit in the PDM.

Q: Does the test light illuminate and flash on and off?

YES: Replace the Radiator Fan Control Relay. Perform BODY VERIFICATION TEST VER - 1. Body Verification Test
NO: Go To 4




4. (N201) RADIATOR FAN CONTROL RELAY CONTROL CIRCUIT OPEN

Turn the ignition off.
Remove the FCM from the PDM.
Measure the resistance of the (N201) Radiator Fan Control Relay Control circuit from the Relay to the FCM PDM 49 way connector.

Q: Is the resistance below 5.0 ohms?

YES: Go To 5
NO: Replace the PDM. Perform BODY VERIFICATION TEST VER - 1. Body Verification Test




5. (N201) RADIATOR FAN CONTROL RELAY CONTROL CIRCUIT SHORTED TO GROUND

Measure the resistance between ground and the (N201) Radiator Fan Control Relay Control circuit at the Relay connection.

Q: Is the resistance below 100 ohms?

YES: Replace the PDM. Perform BODY VERIFICATION TEST VER - 1. Body Verification Test
NO: Replace Front Control Module. Perform BODY VERIFICATION TEST VER - 1. Body Verification Test