GM Service Manual Online
For 1990-2009 cars only

Step

Action

Yes

No

Schematic Reference: Exterior Lights Schematics

Connector End View Reference: Master Electrical Component List

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle

2

  1. Turn ON the ignition, with the engine OFF.
  2. Turn the headlamp switch to the PARK position.

Do all of the park lamps illuminate?

Go to Testing for Intermittent Conditions and Poor Connections

Go to Step 3

3

Is only one lamp inoperative?

Go to Step 12

Go to Step 4

4

Using a scan tool, command the park lamps ON.

Do the park lamps illuminate?

Go to Step 5

Go to Step 6

5

  1. Disconnect the scan tool.
  2. Disconnect the turn signal/multifunction switch.
  3. Connect a 3-amp fused jumper wire between the park lamp switch signal circuit of the turn signal/multifunction switch and a good ground.

Do the park lamps illuminate?

Go to Step 9

Go to Step 8

6

  1. Remove the PARK LPS fuse.
  2. Probe the switch side circuit of the park lps relay with a test lamp that is connected to a good ground.

Does the test lamp illuminate?

Go to Step 7

Go to Step 10

7

Test for the following in the park lamp supply voltage circuit:

    • An open
    • A high resistance
    • A short to ground

Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

Go to Step 16

Go to Step 10

8

Test for an open or high resistance in the park lamp switch signal circuit. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

Go to Step 16

Go to Step 11

9

Inspect for poor connections at the turn signal/multifunction switch. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs .

Did you find and correct the condition?

Go to Step 16

Go to Step 13

10

Inspect for poor connections at the underhood fuse block. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs .

Did you find and correct the condition?

Go to Step 16

Go to Step 14

11

Inspect for poor connections at the body control module (BCM). Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs .

Did you find and correct the condition?

Go to Step 16

Go to Step 15

12

Repair for the following in the voltage supply circuit or the ground circuit of the inoperative lamp:

    • An open
    • A high resistance
    • A short to ground

Refer to Circuit Testing and Wiring Repairs .

Did you complete the repair?

Go to Step 16

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13

Replace the turn signal/multifunction switch. Refer to Turn Signal Multifunction Switch Replacement .

Did you complete the replacement?

Go to Step 16

--

14

Replace the underhood fuse block. Refer to Underhood Electrical Center or Junction Block Bracket Replacement .

Did you complete the replacement?

Go to Step 16

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15

Replace the BCM. Refer to Control Module References for replacement, setup, and programming.

Did you complete the replacement?

Go to Step 16

--

16

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 3