P0481

P0481-COOLING FAN 2 CONTROL CIRCUIT





For a complete wiring diagram refer to Diagrams/Electrical.

- 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.

Diagnostic Test

1. HIGH SPEED RADIATOR FAN RELAY OPERATION

Ignition on, engine not running.

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

No

- Go To 2

2. FUSED B+ CIRCUITS





Turn the ignition off.

Remove the High Speed Radiator Fan Relay.

Using a 12-volt test light connected to ground, probe the Fused B+ circuits in the Relay connection.

Is the voltage above 11.0 volts?

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. HIGH SPEED RADIATOR FAN RELAY RESISTANCE

Measure the resistance of the High Speed Radiator Fan 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 CONTROL CIRCUIT OPEN





Disconnect the FCM 49 way harness connector.

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





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

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 the BODY VERIFICATION TEST. Body Verification Test

No

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