GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

1

Did you perform the Lighting System Diagnostic System Check?

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Go to Step 2

Go to Diagnostic System Check - Lighting Systems

2

  1. Turn the ignition to the ON position.
  2. Press the fog lamp switch to the OFF position.

Are the fog lamps off?

--

Go to Testing for Intermittent Conditions and Poor Connections

Go to Step 3

3

Remove the Fog Lamp Relay.

Do the fog lamps turn off?

--

Go to Step 4

Go to Step 5

4

Replace the Fog Lamp Relay.

Has the repair been made?

--

Go to Step 8

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5

  1. Reinstall the Fog LP Relay.
  2. Inspect for a short to B+ on the fog lamp switched B+. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find a short to B+ on the circuit?

--

Go to Step 7

Go to Step 6

6

Replace the Underhood Accessory Wiring Junction Block.

Has the repair been made?

--

Go to Step 8

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7

Repair a short to B+ on the fog lamps switched B+ feed circuit. Refer to Wiring Repairs in Wiring Systems.

Has the repair been made?

--

Go to Step 8

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8

Operate the system in order to verify the repair.

Did you correct the condition?

--

Go to Diagnostic System Check - Lighting Systems

Go to Step 2