P0481

P0481-COOLING FAN 2 CONTROL CIRCUIT





For a complete wiring diagram Refer to the Wiring Information.

- 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.





Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Pre-Diagnostic Troubleshooting Procedure.

1. HIGH SPEED RADIATOR FAN RELAY OPERATION
1. Ignition on, engine not running.
2. With a scan tool, actuate the High Speed Radiator Fan Relay.

Is the Cooling Fan Relay operating?

Yes

- Refer to the INTERMITTENT CONDITION Diagnostic Procedure. Intermittent Condition Test.

No

- Go To 2

2. FUSED B+ CIRCUITS




1. Turn the ignition off.
2. Remove the Radiator Fan High Relay.
3. Using a 12-volt test light connected to ground, probe the Fused B+ circuits in the Relay connection.

Does the test light illuminate brightly?

Yes

- Go To 3

No

- Repair the open or short to ground in the Fused B+ circuits. Inspect the related fuse and repair as necessary.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.

3. RADIATOR FAN HIGH RELAY RESISTANCE
1. Measure the resistance of the Radiator Fan High Relay Coil.

Is the resistance between 60 to 80 ohms?

Yes

- Go To 4

No

- Replace the Relay.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.

4. RADIATOR FAN HIGH RELAY CONTROL CIRCUIT OPEN




1. Disconnect the FCM 49 way harness connector.
2. Measure the resistance of the Radiator Fan High Relay Control circuit from the Relay connection to the C3 FCM harness connector.

Is the resistance below 5.0 ohms?

Yes

- Go To 5

No

- Repair the open in the Radiator Fan High Relay Control circuit.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.

5. RADIATOR FAN HIGH RELAY CONTROL CIRCUIT SHORTED TO GROUND




1. Measure the resistance between ground and the Radiator Fan High Relay Control circuit at the Relay connection.

Is the resistance below 100 ohms?

Yes

- Repair the short to ground in the Radiator Fan High Relay Control circuit.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.

No

- Go To 6

6. FRONT CONTROL MODULE (FCM)
1. Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Radiator Fan and the Front Control Module (FCM).
2. Look for any chafed, pierced, pinched, or partially broken wires.
3. Look for broken, bent, pushed out or corroded terminals. Verify that there is good pin to terminal contact in the Radiator Fan High Relay and Front Control Module connectors.
4. Search for any Technical Service Bulletins that may apply.

Were there any problems found?

Yes

- Repair as necessary.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

No

- Replace the Front Control Module.
- Perform the BODY VERIFICATION TEST. Body Verification Test.