GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

1

Did you perform the Lighting Systems Diagnostic System Check?

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Go to Step 2

Go to Diagnostic System Check - Lighting Systems

2

  1. Turn the ignition switch to the ON position.
  2. Turn the headlamp switch to the HEAD position.
  3. Turn the headlamp dimmer switch to the LOW position.
  4. Turn the fog lamp switch to the ON position.
  5. Using a test light, backprobe the fog lamp switch harness fog lamp feed circuit to a known good ground.

Is the test lamp on?

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Go to Step 3

Go to Step 5

3

Connect a test lamp between the fog lamp switch harness fog lamp feed circuit and the fog lamp switch ground circuit at the fog lamp switch connector.

Is the test lamp lit?

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Go to Step 4

Go to Step 6

4

Replace the fog lamp switch. Refer to one of the following procedures:

Is the repair complete?

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System OK

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5

Repair the open in the fog lamp feed circuit between the fog lamp switch and the fog lamp relay.Refer to Wiring Repairs .

Is the repair complete?

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System OK

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6

Repair the open in the fog lamp switch ground circuit.Refer to Wiring Repairs Is the repair complete?

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System OK

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