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

Inspect CKT 640 (ORN) for an open between S340 and the inoperative vanity mirror. Refer to Testing for Continuity in Wiring Systems.

Is CKT 640 OK?

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Go to Step 3

Go to Step 5

3

Inspect CKT 1250 (BLK) for an open between S339 and the inoperative vanity mirror. Refer to Testing for Continuity in Wiring Systems.

Is CKT 1250 OK?

--

Go to Step 4

Go to Step 5

4

Replace the vanity mirror. Refer to Vanity Mirror Lamp Replacement in Lighting Systems.

Is the vanity mirror replacement complete?

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Go to Step 6

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5

Repair the suspect wiring. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

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Go to Step 6

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6

Operate the system in order to verify the repair. Did you correct the condition?

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System OK.

Go to Step 2