GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

1

  1. Turn the headlamp to the HEAD position.
  2. Turn the headlamp dimmer switch to the LOW position.
  3. Using a test light backprobe between C201 terminal E12 and ground.

Does the test light illuminate?

--

Go to Step 2

Go to Step 5

2

  1. Disconnect the underhood accessory wiring junction block connector C2.
  2. Using a test lamp backprobe between the underhood accessory wiring junction block harness connector C2 terminal F8 and ground.

Does the test light illuminate?

--

Go to Step 3

Go to Step 4

3

Replace the underhood accessory wiring junction block. Refer to Accessory Wiring Junction Block Replacement in body front end.

Has the repair been made?

--

Go to Daytime Running Lights (DRL) System Check

--

4

Repair the poor connection or open in circuit 12 between C201 terminal E12 and the underhood accessory wiring junction block connector C2 terminal F8.

Has the repair been made?

--

Go to Daytime Running Lights (DRL) System Check

--

5

Replace the headlamp dimmer switch. Refer to Multifunction Turn Signal Lever Replacement - On Vehicle in steering wheel and column.

Has the repair been made?

--

Go to Daytime Running Lights (DRL) System Check

--