GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

Important: The BCM monitors the courtesy lamp relay control CKT 690 (GRY/BLK) for faults. If this circuit is open or shorted to power or ground, a DTC will set.

1

Did you perform the Lighting Diagnostic System Check?

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Go to Step 2

Go to Diagnostic System Check - Lighting Systems

2

Inspect for the following related BCM data parameters. Refer to Scan Tool Data List in Body Control System for typical values and definitions.

    • The driver door jamb switch
    • The pass door jamb switch
    • The side door jamb switch
    • The courtesy lamp relay
    • The inadvertent power relay
    • The dome override switch

Did you find and correct a problem?

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Go to Step 6

Go to Step 3

3

Disconnect the courtesy lamp relay from the relay center.

Did the courtesy/dome lamps turn OFF?

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Go to Step 5

Go to Step 4

4

Repair the short to ground in CKT 156 (WHT).

Is the repair complete?

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Go to Step 6

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5

Replace the courtesy lamp relay.

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