GM Service Manual Online
For 1990-2009 cars only

Backup Lamps Always On Buick

Step

Action

Value(s)

Yes

No

1

Did you perform the Backup Lights System Check?

--

Go to Step 2

Go to Backup Lamp System Check

2

Disconnect the park/neutral position switch connector C1.

Do the backup lamps turn off?

--

Go to Step 3

Go to Step 4

3

Replace the park/neutral position switch. Refer to Park/Neutral Position Switch Replacement in Automatic Transaxle-4T65-E.

Is the repair complete?

--

Go to Backup Lamp System Check

--

4

Does the vehicle have cornering lamps?

--

Go to Step 6

Go to Step 5

5

Remove the perimeter lighting relay from the RH IP fuse block.

Do the backup lamps turn off?

--

Go to Step 7

Go to Step 8

6

Disconnect the perimeter lighting relay connector.

Do the backup lamps turn off?

--

Go to Step 7

Go to Step 8

7

Replace the perimeter lighting relay.

Is the repair complete?

--

Go to Backup Lamp System Check

--

8

Repair the short to voltage in CKT 24 (LT GRN). Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Backup Lamp System Check

--

Backup Lamps Always On Oldsmobile and Pontiac

Step

Action

Value(s)

Yes

No

1

Did you perform the entire Backup Lights System Check?

--

Go to Step 2

Go to Backup Lamp System Check

2

Disconnect the park/neutral position switch connector C1.

Do the backup lamps turn off?

--

Go to Step 3

Go to Step 4

3

Replace the park/neutral position switch. Refer to Park/Neutral Position Switch Replacement in Automatic Transaxle-4T65-E.

Is the repair complete?

--

Go to Backup Lamp System Check

--

4

Is the vehicle equipped with lamp monitoring?

--

Go to Step 5

Go to Step 7

5

Disconnect the lamp monitor control module connector C1.

Do the backup lamps turn off?

--

Go to Step 6

Go to Step 8

6

Inspect CKT 24 (LT GRN) for a short to voltage. Refer to Testing for Continuity in Wiring Systems.

Is CKT 24 (LT GRN) OK?

--

Go to Step 9

Go to Step 7

7

Repair the short to voltage in CKT 24 (LT GRN). Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Backup Lamp System Check

--

8

Inspect CKT 1524 (GRY) for a short to voltage. Refer to Testing for Continuity in Wiring Systems.

Is CKT 1524 (GRY) OK?

--

Go to Step 10

Go to Step 11

9

Replace the lamp monitor control module. Refer to Instrument Panel Lamp Dimmer Replacement in Instrument Panel, Gauges and Console.

Is the repair complete?

--

Go to Backup Lamp System Check

--

10

Repair the short to voltage in CKT 24 (LT GRN) between C406 and S481. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Backup Lamp System Check

--

11

Repair the suspect wiring. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Backup Lamp System Check

--