GM Service Manual Online
For 1990-2009 cars only

Step

Action

Yes

No

Schematic Reference: Fog Lights Schematics

Connector End View Reference: Master Electrical Component List in Wiring Systems.

1

Did you perform the Lighting System Diagnostic System Check?

Go to Step 2

Go to Diagnostic System Check - Lighting Systems

2

  1. Turn the headlamp switch to the PARK position.
  2. Turn the fog lamp switch to the OFF position.

Are the fog lamps illuminated?

Go to Step 3

Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems

3

Remove the fog lamp relay.

Are the fog lamps illuminated?

Go to Step 7

Go to Step 4

4

Using a test lamp connected to ground, probe the control circuit of the fog lamp relay connector.

Does the test lamp illuminate?

Go to Step 5

Go to Step 10

5

  1. Disconnect the fog lamp switch.
  2. Using a test lamp connected to ground, probe the control circuit of the fog lamp relay connector.

Does the test lamp illuminate?

Go to Step 6

Go to Step 9

6

Test the fog lamp relay control circuit for a short to battery positive voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 11

Go to Step 8

7

Test the fog lamp supply voltage circuit for a short to battery positive voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 11

Go to Step 8

8

Replace the fuse block - underhood. Refer to Underhood Electrical Center or Junction Block Replacement in Wiring Systems.

Is the repair complete?

Go to Step 11

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9

Replace the fog lamp switch. Refer to Instrument Panel Multifunction Switch Assembly Replacement in Instrument Panel, Gages, and Console.

Did you complete the replacement?

Go to Step 11

--

10

Replace the fog lamp relay. Refer to Relay Replacement in Wiring Systems.

Is the repair complete?

Go to Step 11

--

11

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 2