GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

1

Did you perform the Interior Lamps System Check?

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Go to Step 2

Go to Interior Lamps System Check

2

  1. Disconnect the interior lamp switch connector.
  2. Connect a fused jumper between the interior lamp switch connector cavity 7 (DK BLU) and ground.

Do the courtesy lamps light?

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Go to Step 3

Go to Step 4

3

Test CKT 150 (BLK) for an open. Refer to Testing for Continuity in Wiring Systems.

Is CKT 150 OK?

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Go to Step 5

Go to Step 7

4

Test CKT 1393 (DK BLU) for an open or short to ground. Refer to Testing for Continuity or Testing for Short to Ground in Wiring Systems.

Is CKT 1393 OK?

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Go to Step 6

Go to Step 7

5

Replace the interior lamp switch. Refer to Instrument Cluster Trim Panel Replacement in Instrument Panel, Gauges and Console.

Is the repair complete?

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Go to Interior Lamps System Check

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6

Replace the body control module (MALL). Refer to Body Control Module Replacement in Body Control System.

Is the repair complete?

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Go to Interior Lamps System Check

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7

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

Is the repair complete?

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Go to Interior Lamps System Check

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