GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

1

Verify that connector  C299 is disconnected.

Is the connector disconnected?

--

Go to Step 3

Go to Step 2

2

Disconnect C299 and secure connector ends to the harness.

Has the repair been made?

--

Go to Interior Lights Dimming System Check

--

3

  1. Disconnect the Daytime Running Lamp(s) (DRL) control module connector C1.
  2. Using a test light, backprobe the DRL control module harness connector C1 terminal C to ground.
  3. Turn the display switch to the OFF position.
  4. Turn the ignition to the RUN position.

Did the test light illuminate?

--

Go to Step 4

Go to Step 7

4

Inspect circuit 588 for a short to B+.

Is there a short on circuit 588?

--

Go to Step 5

Go to Step 6

5

Repair a short to B+ on circuit 588.

Is there a short on circuit 588?

--

Go to Interior Lights Dimming System Check

--

6

Replace the accessory switch. Refer to Accessory Switch Replacement .

Has the repair been made?

--

Go to Interior Lights Dimming System Check

--

7

Replace the DRL control module. Refer to Daytime Running Lights (DRL) Control Module Replacement .

Has the repair been made?

--

Go to Interior Lights Dimming System Check

--