GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

1

Did you perform the Lighting System Diagnostic System Check?

--

Go to Step  2

Go to Diagnostic System Check - Lighting Systems

2

Is the inoperative lamp in the radio control switches?

--

Go to Radio Display/Illumination Inoperative with Park Lamps On in Entertainment

Go to Step 3

3

  1. Turn the headlamp switch to the PARK position and the dimmer switch to the HIGH position on the headlamp and the instrument panel (IP) dimmer switch.
  2. Use a test lamp in order to backprobe between the inoperable lamp harness connector CKT 8 and ground.

Did the test lamp light?

--

Go to Step 5

Go to Step 4

4

  1. Repair the following conditions in CKT 8 between S203 and the inoperable component.
  2. • A poor connection
    • An open
  3. Inspect the system

Is the repair complete?

--

Go to Step 8

--

5

Use a test lamp in order to backprobe the inoperable lamp harness connector between CKT 8 and the following ground circuits:

    • CKT 750
    • CKT 1450
    • CKT 1550
    • CKT 150
    • CKT 650

Did the test lamp light?

--

Go to Step 7

Go to Step 6

6

  1. Repair the following conditions in the ground circuit between the inoperable component (CKT 750, CKT 1450, CKT 1550, CKT 150 or CKT 650) and G200, G302 and G401:
  2. • A poor connection
    • An open
  3. Inspect the system.

Is the repair complete?

--

Go to Step 8

--

7

  1. Replace the bulb/inoperable component.
  2. Inspect the system.

Is the repair complete?

--

Go to Step 8

--

8

Operate the system in order to verify the repair.

Did you correct the condition?

--

system OK

Go to Step  2