For 1990-2009 cars

Step | Action | Yes | No
--- | --- | --- | ---
Schematic Reference: Exterior Lights Schematics Connector End View Reference: Master Electrical Component List
1 | Did you perform the Diagnostic System Check - Vehicle? | Go to Step 2 | Go to Diagnostic System Check - Vehicle
2 |

1. Install the scan tool.
2. Turn ON the ignition, with the engine OFF.
3. With the scan tool, command the Backup Lamp Relay Cmd. ON and OFF from the rear integration module (RIM) output controls data list.
4. Listen for the backup lamp relay to click as it is cycled from ON to OFF.

Does the backup lamp relay turn ON and OFF with each command?

Go to Step 5

Go to Step 3

3 |

1. Turn OFF the ignition.
2. Disconnect the backup lamp relay. Refer to Relay Replacement .
3. Turn ON the ignition, with the engine OFF.
4. Probe the backup lamp relay control side supply voltage circuit with a test lamp that is connected to ground.

Does the test lamp illuminate?

Go to Step 4

Go to Step 13

4 |

1. Turn OFF the ignition.
2. Connect a test lamp between the reverse lamp relay control side supply voltage circuit and the reverse lamp relay control circuit.
3. Turn ON the ignition, with the engine OFF.
4. With a scan tool, command the Backup Lamp Relay ON and OFF.

Does the test lamp turn ON and OFF with each command?

Go to Step 11

Go to Step 8

5 |

1. Turn OFF the ignition.
2. Disconnect the backup lamp relay. Refer to Relay Replacement .
3. Turn ON the ignition, with the engine OFF.
4. Probe the backup lamp relay control side supply voltage circuit with a test lamp that is connected to ground.

Does the test lamp illuminate?

Go to Step 6

Go to Step 14

6 |

1. Turn OFF the ignition.
2. Connect a 10-amp fused jumper between the backup lamp relay switch side supply voltage circuit and the backup lamp supply voltage circuit.
3. Turn ON the ignition, with the engine OFF.

Do both backup lamps illuminate?

Go to Step 11

Go to Step 7

7 |

1. Turn OFF the ignition.
2. Remove the inoperative backup lamp bulb.
3. Connect a test lamp between the backup lamp supply voltage circuit and the backup lamp ground circuit.
4. Turn ON the ignition, with the engine OFF.

Does the test lamp illuminate?

Go to Step 10

Go to Step 9

8 | Test the backup lamp relay control circuit for an open, high resistance, or short to voltage. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition? | Go to Step 19 | Go to Step 12
9 | Test the inoperative backup lamp supply voltage circuit for an open, high resistance, or short to ground. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition? | Go to Step 19 | Go to Step 15
10 | Inspect for poor connections at the backup lamp bulb. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs . Did you find and correct the condition? | Go to Step 19 | Go to Step 17
11 | Inspect for poor connections at the backup lamp relay. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs . Did you find and correct the condition? | Go to Step 19 | Go to Step 16
12 | Inspect for poor connections at the harness connector of the rear integration module (RIM). Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs . Did you find and correct the condition? | Go to Step 19 | Go to Step 18
13 | Locate and repair an open or high resistance in the backup lamp relay control side supply voltage circuit. Refer to Circuit Testing and Wiring Repairs . Did you complete the repair? | Go to Step 19 | --
14 | Locate and repair an open or high resistance in the backup lamp relay switch side supply voltage circuit. Refer to Circuit Testing and Wiring Repairs . Did you complete the repair? | Go to Step 19 | --
15 | Locate and repair an open or high resistance in the inoperative backup lamp ground circuit. Refer to Circuit Testing and Wiring Repairs . Did you complete the repair? | Go to Step 19 | --
16 | Replace the backup lamp relay. Refer to Relay Replacement . Did you complete the replacement? | Go to Step 19 | --
17 | Replace the backup lamp bulb. Refer to Tail Lamp Replacement . Did you complete the replacement? | Go to Step 19 | --
18 | Replace the RIM. Refer to Control Module References for replacement, setup, and programming. Did you complete the replacement? | Go to Step 19 | --
19 | Operate the system in order to verify the repair. Did you correct the condition? | System OK | Go to Step 2