GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

1

  1. Turn the ignition OFF.
  2. Connect a scan tool.
  3. Turn the ignition to the ON position.
  4. Using the scan tool, check for any DTCs in the body control module (BCM).

Does the scan tool show any DTCs?

--

Go to Diagnostic System Check - Body Control System in Body Control System

Go to Step 2

2

Turn the park lamps ON.

Do the park lamps function properly?

--

Go to Step 3

Go to Park Lamps Inoperative

3

  1. Remove the inoperative bulb.
  2. Inspect the filament.

Is the lamp open?

--

Go to Step 4

Go to Step 5

4

Replace the bulb. Refer to Rear License Lamp Replacement in Bumper.

Is the repair complete?

--

System OK

--

5

Connect a test lamp from terminal A to ground.

Does the test lamp light?

--

Go to Step 7

Go to Step 6

6

Locate and repair CKT 2509 (BRN) LT side or CKT 2609 (BRN/WHT) RT side for an open between the lamp and the rear lamps bussing block.

Is the repair complete?

--

System OK

--

7

Locate and repair CKT 1750 (BLK) for an open to ground.

Is the repair complete?

--

System OK

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