For 1990-2009 cars

Step | Action | Yes | No
--- | --- | --- | ---
Schematic Reference: Fog 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. Place the rear fog lamp switch in the OFF position.
4. With a scan tool, observe the Rear Fog Lamp Relay Cmd. parameter in the rear integration module (RIM) data list.

Does the scan tool indicate the rear fog lamp relay cmd. parameter is OFF?

Go to Step 3

Go to Step 5

3 |

1. Turn OFF the ignition.
2. Disconnect the rear fog lamp relay. Refer to Relay Replacement .
3. Turn ON the ignition, with the engine OFF.

Do the rear fog lamps turn OFF?

Go to Step 4

Go to Step 13

4 |

1. Turn OFF the ignition.
2. Connect a test lamp between the rear fog lamp relay control side supply voltage circuit and the rear fog lamp relay control circuit.
3. Place the rear fog lamp switch in the OFF position.
4. Turn ON the ignition, with the engine OFF.

Does the test lamp illuminate?

Go to Step 6

Go to Step 12

5 |

1. Turn OFF the ignition.
2. Disconnect the C2 harness connector at the turn signal/multifunction switch.
3. Turn ON the ignition, with the engine OFF.
4. With a scan tool, observe the Rear Fog Lamp Relay Cmd. parameter in the rear integration module (RIM) data list..

Does the scan tool indicate the Rear Fog Lamp Relay Cmd. parameter is OFF?

Go to Step 11

Go to Step 7

6 | Test the rear fog lamp relay control circuit for a short to ground. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition? | Go to Step 18 | Go to Step 10
7 | Test the rear fog lamp switch signal circuit for a short to ground. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition? | Go to Step 18 | Go to Step 8
8 |

1. Turn OFF the ignition.
2. Disconnect the C3 harness connector at the instrument panel module (IPM).
3. Turn ON the ignition, with the engine OFF.

Do the rear fog lamps turn OFF?

Go to Step 9

Go to Step 10

9 | Inspect for poor connections at the harness connector of the IPM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs . Did you find and correct the condition? | Go to Step 18 | Go to Step 17
10 | 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 18 | Go to Step 14
11 | Inspect for poor connections at the harness connector of the turn signal/multifunction switch. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs . Did you find and correct the condition? | Go to Step 18 | Go to Step 15
12 | Inspect for poor connections at the rear fog lamp relay. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs . Did you find and correct the condition? | Go to Step 18 | Go to Step 16
13 | Locate and repair a short to voltage in the rear fog lamp supply voltage circuit. Refer to Circuit Testing and Wiring Repairs . Did to complete the repair? | Go to Step 18 | --
14 | Replace the RIM. Refer to Control Module References for replacement, setup, and programming. Did you complete the replacement? | Go to Step 18 | --
15 | Replace the turn signal/multifunction switch. Refer to Turn Signal Multifunction Switch Replacement . Did you complete the replacement? | Go to Step 18 | --
16 | Replace the rear fog lamp relay. Refer to Relay Replacement . Did you complete the replacement? | Go to Step 18 | --
17 | Replace the IPM. Refer to Control Module References for replacement, setup, and programming. Did you complete the replacement? | Go to Step 18 | --
18 | Operate the system in order to verify the repair. Did you correct the condition? | System OK | Go to Step 2