Schematic Reference: Fog Lights Schematics .

Connector End View Reference: Component Connector End Views , or Master Electrical Component List

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle

Verify the front fog lamps are inoperative.

Do the front fog lamps operate normally?

Go to Testing for Intermittent Conditions and Poor Connections

Go to Step 3

Is only one front fog lamp inoperative?

Go to Step 4

Go to Step 6

Inspect the inoperative bulb and socket for an open filament or poor terminal contact and repair or replace as necessary. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

System OK

Go to Step 5

Test the ground circuit of the inoperative lamp for a high resistance or an open.

Did you find and correct the condition?

System OK

Repair the fog lamp supply circuit of the inoperative lamp. Refer to Wiring Repairs .

Engine OFF, turn the key to RUN and the headlamp switch to PARK.

Do the courtesy lamps illuminate?

Go to Step 7

Go to Courtesy Lamps Inoperative

Inspect the fog lamp fuse.

Is the fuse open?

Repair the fog lamp supply circuit of the inoperative lamp for a short to ground. Refer to Wiring Repairs .

Go to Step 8

1. Place the front fog lamp switch in the ON position.
2. Test for a ground signal at the front fog lamp relay control circuit terminal in the underhood fuse block connector. Refer to Circuit Testing and Wiring Repairs .

Was a ground signal present?

Go to Step 11

Go to Step 9

Test the front fog lamp switch signal and ground circuits for an open or high resistance. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct a condition?

System OK

Go to Step 10

1. Remove the fog lamp switch.
2. Place a fused jumper between the fog lamp switch signal and ground connector terminals.
3. Test for a ground signal at the front fog lamp relay control circuit terminal in the underhood fuse block. Refer to Circuit Testing and Wiring Repairs .

Was a ground signal present?

Replace the front fog lamp switch. Refer to Headlamp Switch Replacement .

Go to Step 12

Test for an open or high resistance in the front fog lamp supply voltage circuit. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct a condition?

System OK

Replace the underhood fuse block. Refer to Underhood Electrical Center or Junction Block Replacement .

Test the fog lamp relay control circuit for an open high resistance or a short to voltage. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

System OK

Go to Step 13

Inspect for poor connections at the harness connector of the body control module (BCM). Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

System OK

Replace the BCM. Refer to Control Module References , for replacement, setup, and programming.