GM Service Manual Online
For 1990-2009 cars only

Step

Action

Yes

No

Schematic Reference: Headlights 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 headlamp switch.
  2. Disconnect the headlamp dimmer switch connector C201C.
  3. Connect a fused jumper wire between the headlamp dimmer switch output circuit of connector C201C to good ground.

Do the High beams illuminate?

Go to Step 5

Go to Step 4

4

Repair the open in the headlamp dimmer switch output circuit between engine wiring harness junction block and dimmer switch. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 6

--

5

Replace the headlamp dimmer switch. Refer to Multifunction, Turn Signal, and Hazard Switch Replacement - On Vehicle in Steering Wheel and Column.

Did you complete the replacement?

Go to Step 6

--

6

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 3