GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

1

  1. Place the ignition switch in RUN (Engine OFF).
  2. Place the transmission gear select lever in REVERSE.

Are both backup lamps inoperative?

--

Go to Step 5

Go to Step 2

2

  1. Remove the lens cover from the inoperative lamp.
  2. Connect a test lamp from the center terminal of the backup lamp socket to ground.

Did the test lamp light?

--

Go to Step 3

Go to Step 4

3

Repair the open in CKT 150 (BLK) between the inoperative backup lamp and ground.

Is the repair complete?

--

System OK

--

4

Repair the open in CKT 24 (LT GRN) between Splice S900 and the inoperative backup lamp?

Is the repair complete?

--

System OK

Go to Step 5

5

  1. Remove the lens cover from an inoperative lamp.
  2. Connect the test lamp from the center terminal of the backup lamp socket to ground.

Did the test lamp light?

--

Go to Step 6

Go to Step 7

6

Repair the open in CKT 150 (BLK) between the inoperative backup lamp and ground.

Is the repair complete?

--

System OK

--

7

Connect the test lamp from terminal B at connector C405 to ground.

Did the test lamp light?

--

Go to Step 8

Go to Step 9

8

Repair the open in CKT 24 (LT GRN) between C405 and the backup lamps.

Is the repair complete?

--

System OK

--

9

  1. Disconnect the backup lamp switch connector at the transmission.
  2. Connect the test lamp from terminal B (Automatic) or terminal C1 (Manual) to chassis ground.

Did the test lamp light?

--

Go to Step 10

Go to Step 11

10

Repair the open in CKT 24 (LT GRN) between the backup lamp switch and C405.

Is the repair complete?

--

System OK

--

11

Connect the test lamp from the backup lamp switch terminal A (Automatic) or terminal C2 (Manual) to chassis ground.

Did the test lamp light?

--

Go to Step 12

Go to Step 13

12

Replace the backup lamp switch.

Is the repair complete?

--

System OK

--

13

Connect the test lamp from connector C200 (terminal 22) to ground.

Did the test lamp light?

--

Go to Step 14

Go to Step 15

14

Repair the open in CKT 8, CKT 139 (PNK), or CKT 441 (BRN) between C200 and the backup lamp switch.

Is the repair complete?

--

System OK

--

15

Repair the open in CKT 145 (PNK) between the IP fuse block and C200.

Is the repair complete?

--

System OK

--