GM Service Manual Online
For 1990-2009 cars only

Step

Action

Yes

No

Schematic Reference: Exterior Lights Schematics

1

Did you perform the Lighting Diagnostic System Check?

Go to Step 2

Go to Diagnostic System Check - Lighting Systems

2

Verify the fault is present.

Does the system operate normally?

Go to Testing for Electrical Intermittents in Wiring Systems

Go to Step 3

3

  1. Turn ON the ignition with the engine OFF.
  2. Turn ON the right turn signal.

Does the turn signal function properly?

Go to Step 4

Go to Turn Signal Lamps Inoperative - Left or Right Side

4

  1. Connect the Scan Tool .
  2. With the scan tool, read the right turn signal input in the Body Control Module (BCM).

Does the scan tool show ON?

Go to Step 5

Go to Step 8

5

  1. Disconnect the instrument cluster. Refer to Instrument Cluster Replacement in Instrument Panel, and Gauges and Console.
  2. Connect a test lamp between the turn signal lamp feed circuit and a good ground.

Does the test lamp illuminate or flash?

Go to Step 6

Go to Step 7

6

  1. Inspect the instrument cluster printed circuit and the right turn signal indicator filament.
  2. Repair as needed. Refer to Instrument Cluster Bulb Replacement in Instrument Panel, Gauges and Console.

Did you find and correct the condition?

Go to Step 10

Go to Step 9

7

Repair the open in the turn signal lamp feed circuit between the body wiring harness junction block and the instrument cluster. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 10

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8

Repair the open in the turn signal lamp feed circuit between the body wiring harness junction block and the BCM. Refer to Wiring Repairs in Wiring Systems. If no open is found, replace the BCM. Refer to Body Control Module Replacement in Body Control System.

Did you complete the repair?

Go to Step 5

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9

Repair the open in the instrument cluster ground circuit. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 10

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10

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 3