GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

1

  1. Turn the headlamp switch to the HEAD position.
  2. Turn the headlamp dimmer switch to the HIGH position.

Does the high beam indicator illuminate?

--

Go to Step 2

Go to Step 3

2

Replace the underhood accessory wiring junction block. Refer to Underhood Electrical Center or Junction Block Replacement in Wiring Systems.

Is the repair complete?

--

Go to Diagnostic System Check - Lighting Systems

--

3

  1. Leave the headlamp dimmer switch in the HIGH position.
  2. Using a test light, backprobe between the harness connector C201 terminal A1 to ground.

Does the test light illuminate?

--

Go to Step 5

Go to Step 4

4

Repair a poor connection or an open in circuit 1200 between the underhood accessory wiring junction block connector C2 terminal F11 and connector C201 terminal A1.

Is the repair complete?

--

Go to Diagnostic System Check - Lighting Systems

--

5

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

Is the repair complete?

--

Go to Diagnostic System Check - Lighting Systems

--