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

Disconnect the fog lamp switch.

Did the fog lamps turn off?

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Go to Step 3

Go to Step 4

3

Replace the fog lamp switch. Refer to Fog Lamp Switch replacement Fog Lamp Switch Replacement .

Is the repair complete?

--

System OK

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4

Replace the fog lamp relay with a known good one.

Did the fog lamps turn off?

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Go to Step 5

Go to Step 6

5

Replace the fog lamp relay. Refer to Fog Lamp Relay Replacement .

Is the repair complete?

--

System OK

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6

Remove the fog lamp relay.

Check for continuity to ground at terminal 85 of the fog lamp relay receptical.

Is ground present?

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Go to Step 7

Go to Step 8

7

Repair short to ground in the fog lamp switch output circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and repair the condition?

--

System OK

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8

Repair the short to power in the fog lamp feed circuit. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

System OK

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