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

Verify the proper operation of the headlamps.

Are the headlamps operating properly?

Go to Step 3

Go to Headlamps Inoperative - Low Beams

3

  1. Turn the ignition switch to the ON position.
  2. Place the headlamp switch to the PARK position.
  3. Backprobe the headlamp switch indicator supply voltage circuit of the headlamp switch connector with a test lamp that is connected to a good ground.

Does the test lamp illuminate?

Go to Step 5

Go to Step 4

4

Repair an open or high resistance in the headlamp switch indicator supply voltage circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Is the repair complete?

Go to Step 6

--

5

Replace the headlamp switch. Refer to Headlamp Switch Replacement .

Is the replacement complete?

Go to Step 6

--

6

  1. Connect all connectors and components that were disconnected.
  2. Verify that the low beam indicator operates properly.

Does the low beam indicator operate properly?

System OK

Go to Step 2