GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

1

  1. Turn the ignition OFF.
  2. Roll down the windows.
  3. Close all of the doors.
  4. Connect a scan tool.
  5. Turn the ignition to the ON position.
  6. Using the scan tool, inspect for any DTCs in the body control module (BCM).

Does the scan tool show any DTCs?

--

Go to Diagnostic System Check - Body Control System in Body Controls

Go to Step 2

2

Connect a test lamp (back probe) from CKT 2140 (ORN) at the inoperative switch to ground.

Does the test lamp light?

--

Go to Step 4

Go to Step 3

3

Locate and repair the open in CKT 2140 (ORN) between the fuse and the switch.

Is the repair complete?

--

System OK

--

4

Depress the inoperative switch to the unlock position.

Do the doors unlock?

--

Go to Step 8

Go to Step 5

5

  1. Connect a test lamp (back probe) from CKT 194 (WHT) to ground.
  2. While probing, depress the switch to the unlock position.

Does the test lamp light?

--

Go to Step 6

Go to Step 7

6

Locate and repair the open in CKT 194 (WHT) between switch and the BCM.

Is the repair complete?

--

System OK

--

7

Replace the inoperative switch. Refer to Door Lock Switch Replacement .

Is the repair complete?

--

System OK

--

8

  1. Connect a test lamp (back probe) from CKT 195 (LT BLU) to ground.
  2. While probing, depress the switch to the lock position.

Does the test lamp light?

--

Go to Step 9

Go to Step 7

9

Locate and repair the open in CKT 195 (LT BLU) between the switch and the lock relay.

Is the repair complete?

--

System OK

--