GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

1

Was the Interior Lamps System Check performed?

--

Go to Step 2

Go to Interior Lamps System Check

2

  1. Disconnect the connector at the headlamp switch.
  2. Connect a J 39200 DMM between the headlamp switch connector, cavity R for CKT 150 (BLK), and ground.

Is continuity present?

--

Go to Step 4

Go to Step 3

3

Repair the open in CKT 150 (BLK) between the headlamp switch and ground G201.

Do the dome lamps operate from the dome lamp switch?

--

Go to Interior Lamps System Check

Go to Step 4

4

  1. Connect a J 39200 DMM between pin M and pin R of the headlamp switch.
  2. Adjust the instrument panel dimmer switch adjustment knob to the dome lamp switch detent position.

Is continuity present?

--

Go to Step 5

Go to Step 6

5

Repair the open in CKT 156 (WHT) between splice S226 and the headlamp switch.

Do the dome lamps operate from the dome lamp switch?

--

Go to Interior Lamps System Check

Go to Step 6

6

Replace the headlamp switch.

Do the dome lamps operate from the dome lamp switch?

--

Go to Interior Lamps System Check

Go to Step 4