GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

Important: A short to ground will cause an open fuse(s). Before performing this diagnostic procedure, inspect the fuse(s) for an open.

1

Inspect the body control module (BCM) for stored DTCs. Refer to Diagnostic Trouble Code (DTC) List/Type in Body Control Systems.

Does the BCM have any stored DTCs?

--

Go to Step 2

Go to Step 3

2

Correct any code setting conditions that exist. Refer to Diagnostic Trouble Code (DTC) List/Type in Body Control System.

Is the repair complete?

--

Go to Daytime Running Lights (DRL) System Check

--

3

Exchange the park lamp relay with a known good relay from the underhood junction block.

Do the park lamps turn off?

--

Go to Step 4

Go to Step 5

4

Replace the faulty relay.

Is the repair complete?

--

Go to Daytime Running Lights (DRL) System Check

--

5

Disconnect the turn/headlamp switch assembly connector C1.

Do the park lamps turn off?

--

Go to Step 6

Go to Step 7

6

Replace the turn/headlamp switch assembly. Refer to Multifunction Turn Signal Lever Replacement - On Vehicle in Steering Wheel and Column-Standard.

Is the repair complete?

--

Go to Daytime Running Lights (DRL) System Check

--

7

Disconnect the underhood junction block connector C2.

Do the front park lamps turn off?

--

Go to Step 8

Go to Step 9

8

Disconnect the underhood junction block connector C3.

Do the rear park lamps turn off?

--

Go to Step 10

Go to Step 11

9

Repair the short to B+ in CKT 9 between the underhood junction block and the lit lamp. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Daytime Running Lights (DRL) System Check

--

10

Replace the underhood junction block. Refer to Underhood Fuse Block Replacement in Engine Electrical.

Is the repair complete?

--

Go to Daytime Running Lights (DRL) System Check

--

11

Disconnect the right IP junction block connector C3.

Do all of the rear lamps turn off?

--

Go to Step 13

Go to Step 12

12

Repair the short to B+ in CKT 9 between the right IP junction block and the lit lamp. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Daytime Running Lights (DRL) System Check

--

13

Replace the right IP junction block.

Is the repair complete?

--

Go to Daytime Running Lights (DRL) System Check

--