For 1990-2009 cars

Step | Action | Yes | No
--- | --- | --- | ---
1 | Did you perform the Diagnostic System Check - Vehicle? | Go to Step 2 | Go to Diagnostic System Check - Vehicle
2 |

1. Turn ON the ignition, with the engine OFF.
2. Apply the park brake.
3. Place the gear selector in the REVERSE position.

Do both backup lamps illuminate?

Go to Testing for Intermittent Conditions and Poor Connections

Go to Step 3

3 | Is only one lamp inoperative? | Go to Step 4 | Go to Step 5
4 |

1. Disconnect the inoperative backup lamp connector.
2. Probe the backup lamp supply voltage circuit of the backup lamp connector with a test lamp that is connected to a good ground.

Does the test lamp illuminate?

Go to Step 8

Go to Step 9

5 |

1. Turn OFF the ignition.
2. Disconnect the park neutral position switch connector.
3. Turn ON the ignition, with the engine OFF.
4. Probe the battery positive voltage circuit of the connector with a test lamp that is connected to a good ground.

Does the test lamp illuminate?

Go to Step 6

Go to Step 10

6 |

1. Turn OFF the ignition.
2. Connect a 10-amp fused jumper wire between the battery positive voltage circuit of the switch and the backup lamp supply voltage circuit of the switch.

Do the backup lamps illuminate?

Go to Step 7

Go to Step 11

7 | Inspect for poor connections at the harness connector of the switch. Did you find and correct the condition? | Go to Step 13 | Go to Step 12
8 | Repair an open or high resistance in the ground circuit of the inoperative backup lamp. Did you complete the repair? | Go to Step 13 | --
9 | Repair an open or high resistance in the backup lamp supply voltage circuit of the inoperative backup lamp. Did you complete the repair? | Go to Step 13 | --
10 | Repair an open, high resistance, or short to ground in the battery positive voltage circuit of the switch. Did you complete the repair? | Go to Step 13 | --
11 | Repair an open or high resistance in the backup lamp supply voltage circuit between the switch and the backup lamps. Did you complete the repair? | Go to Step 13 | --
12 | Replace the switch. Did you complete the replacement? | Go to Step 13 | --
13 | Operate the system in order to verify the repair. Did you correct the condition? | Go to Step 13 | Go to Step 2