GM Service Manual Online
For 1990-2009 cars only

Step

Action

Yes

No

Schematic Reference: Headlights/Daytime Running Lights (DRL) Schematics

Connector End View Reference: Lighting Systems Connector End Views or Computer/Integrating Systems Connector End Views in Computer/Integrating Systems

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle in Vehicle DTC Information

2

Verify that the flash to pass (FTP) is inoperative.

Does the FTP operate normally?

Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems

Go to Step 3

3

Do the high beam headlamps operate normally?

Go to Step 4

Go to Symptoms - Lighting Systems

4

  1. Turn the key to RUN with the engine OFF.
  2. Connect a fused jumper from ground to the flash to pass switch signal terminal of the turn signal/multifunction switch connector.

Do the high beam headlamps illuminate?

Go to Step 6

Go to Step 5

5

Test the flash to pass signal circuit for an open or high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct a condition?

Go to Step 10

Go to Step 7

6

Inspect for poor connections at the harness connector of the turn signal/multifunction switch. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 10

Go to Step 9

7

Inspect for poor connections at the harness connector of the body control module (BCM). Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 10

Go to Step 8

8

Replace the BCM. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming.

Did you complete the replacement?

Go to Step 10

--

9

Replace the turn signal/multifunction switch. Refer to Turn Signal Multifunction Switch Replacement in Steering Wheel and Column.

Did you complete the repair?

Go to Step 10

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10

  1. Use the scan tool in order to clear any induced DTCs.
  2. Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 3