Diagnostic Test

Turn the ignition on.

With the scan tool, clear all BCM DTC's.

Turn the Fog Lamps on.

With the scan tool, read the DTC information.

Does the scan tool read: Rear Fog Relay Circuit Low? 

Yes 

1. Go to step  2).

No 

1. The condition is not present at this time. Monitor scan tool parameters while wiggling the related wire harness. Refer to any Technical Service Bulletins that may apply. Visually inspect the related wiring harness and connector terminals.
2. Perform BODY VERIFICATION TEST .

Turn the ignition off.

Disconnect the Rear Fog Relay.

Measure the resistance between ground and the Rear Fog Relay Control circuit.

Is the resistance below 5.0 ohms? 

Yes 

1. Repair the Rear Fog Relay Control circuit for a short to ground.
2. Perform BODY VERIFICATION TEST .

No 

1. Go to step  3).

Turn the ignition off.

Disconnect the Rear Fog Relay harness connector from the Junction Block.

Measure the voltage of the Rear Fog Relay harness connector coil side feed circuit to ground.

Is the voltage above 10.0 volts? 

Yes 

1. Replace the Rear Fog Lamp Relay.
2. Perform BODY VERIFICATION TEST .

No 

1. Replace the Body Control Module.
2. Perform BODY VERIFICATION TEST .