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?

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Go to Step 2

Go to Diagnostic System Check - Lighting Systems

2

  1. Turn the ignition on.
  2. Shift the gear selector lever to the REVERSE position.

Do the backup lamps turn on?

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Go to Testing for Intermittent Conditions and Poor Connections

Go to Step 3

3

  1. Disconnect the park/neutral position switch.
  2. Connect a test lamp to a known good ground and probe the B+ feed for the park/neutral position switch.

Does the test lamp turn on?

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Go to Step 4

Go to Step 8

4

Install a fused jumper across the B+ feed and the switched side of the park/neutral position switch.

Do the backup lamps turn on?

--

Go to Step 5

Go to Step 6

5

Adjust or replace the park/neutral position switch. Refer to Park/Neutral Position Switch Adjustment in Automatic Transaxle-4T65-E.

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Go to Step 9

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6

Inspect for a short to ground in the backup lamps switched circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

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Go to Step 7

Go to Step 8

7

Repair a poor connection or an open in the backup lamps switched circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Has the repair been made?

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Go to Step 9

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8

Repair a poor connection or an open in the park/neutral position switch B+ feed. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

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Go to Step 9

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9

Operate the system in order to verify the repair.

Did you correct the condition?

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Go to Diagnostic System Check - Lighting Systems

Go to Step 2