GM Service Manual Online
For 1990-2009 cars only

Step

Action

Yes

No

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

1

Did you perform the Lighting System Diagnostic System Check?

Go to Step 2

Go to Diagnostic System Check - Lighting Systems

2

  1. Turn the ignition switch to the ON position.
  2. Turn the headlamp switch to the HEAD position.
  3. Push the turn signal switch forward to turn the high beam headlamps on.
  4. Verify that the high beam headlamps operate properly.

Do the high beams operate properly?

Go to Step 3

Go to Headlamps Inoperative - High Beams

3

  1. Disconnect the BCM connector C1.
  2. Pull and hold the Flash-to-Pass switch.
  3. Probe the high beam On/Off circuit (M50) of the BCM C1 connector with a test light that is connected to a known good ground.

Does the test lamp illuminate?

Go to Step 7

Go to Step 4

4

  1. Disconnect the turn signal switch connector
  2. Probe the battery supply voltage circuit (A8) of the turn signal switch with a test light that is connected to a known good ground.

Does the test lamp illuminate?

Go to Step 6

Go to Step 5

5

Repair an open or high resistance in the battery supply voltage circuit (A8) of the turn signal switch. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 8

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6

Replace the turn signal switch. Refer to Turn Signal Switch Replacement - On Vehicle in Steering Wheel and Column - Tilt.

Did you complete the repair?

Go to Step 8

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7

Replace the BCM. Refer to Body Control Module Replacement in Body Control System.

Did you complete the repair?

Go to Step 8

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8

  1. Connect all connectors and components that were disconnected.
  2. Verify that the flash to pass system operates properly.

Does the flash to pass system operate properly?

System OK

Go to Step 2