Circuit Operation

Fog Lamps
Visually inspect the fog lamps. Check the resistance through the lamp.
Check connections / terminals for damage or corrosion.
Repair/replace as needed.
If this component is good, go to the next item indicated on the Complaint-Condition Chart.

Fog Lamp Relay
The Window, RR Defog, Fog Lamp and A/C relays are interchangeable with each other.
Substitute another relay to see if the problem is fixed.
Replace as needed.
If this component is good, go to the next item indicated on the Complaint-Condition Chart.

Headlamp Switch
Refer to Lever Combination Switch (LCS) for testing.Testing and Inspection
Repair/replace as needed.
If this component is good go to the next item indicated on the Complaint-Condition Chart.

Fog Lamp Switch
Check the fog lamp switch illumination bulb. It should be lit when the headlamp switch is in PARK or HDLP. It should not be lit if the headlamp and fog lamp switches are Off. The fog lamp relay should click when the fog lamp switch is turned ON and click again when the fog lamp switch is turned Off.
Repair/replace as needed.
If this component is good, go to the next item indicated on the Complaint-Condition Chart.

I/P Dimmer
Perform the following checks at the instrument panel dimmer harness connector, with the instrument panel dimmer disconnected.
Pin A - Continuity to ground
Pin B - Battery voltage with park lights On
Pin C - Battery voltage with park lights On
Repair/replace as needed.