GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

1

Was the Lighting System Diagnostic System Check performed?

--

Go to Step 2

Go to the Lighting System Diagnostic System Check

2

With the fog lamps turned on, test for positive battery voltage at terminal B of the fog lamp that is not working.

Is battery voltage present?

--

Go to Step 3

Go to Step 4

3

Test terminal A of the fog lamp for continuity to ground.

Is ground present

--

Go to Step 5

Go to Step 6

4

Repair the open in CKT 34

Is the repair complete?

--

System OK

--

5

Replace the fog lamp bulb.

Is the repair complete

--

System OK

--

6

Repair the open in CKT 150.

Is the repair complete?

--

System OK

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