For 1990-2009 cars

Step | Action | Yes | No
--- | --- | --- | ---
Schematic Reference: Exterior Lights Schematics
1 | Did you perform the Lighting System Diagnostic System Check? | Go to Step 2 | Go to Diagnostic System Check - Lighting Systems
2 |

1. Turn ON the ignition, with the engine OFF.
2. Place the headlamp switch in the PARK position.

Do the park lamps illuminate?

Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems

Go to Step 3

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

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

Does the test lamp illuminate?

Go to Step 12

Go to Step 13

5 | With a scan tool, command the park lamps ON. Do the park lamps illuminate? | Go to Step 6 | Go to Step 7
6 |

1. Place the headlamp switch in the OFF position.
2. Turn OFF the ignition.
3. Disconnect the body control module (BCM).
4. Place the headlamp switch in the PARK position.
5. Probe the park lamp switch control circuit with a test lamp that is connected to a good ground.

Does the test lamp illuminate?

Go to Step 9

Go to Step 8

7 |

1. Disconnect the park lamp relay.
2. Connect a 15-amp fused jumper wire between the switch side battery positive voltage circuit of the park lamp relay and the park lamp supply voltage circuit of the park lamp relay.

Do the park lamps illuminate?

Go to Step 10

Go to Step 14

8 | Test for an open or high resistance in the park lamp switch control circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 18 | Go to Step 11
9 | Inspect for poor connections at the harness connector of the BCM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 18 | Go to Step 15
10 | Inspect for poor connections at the park lamp relay. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 18 | Go to Step 16
11 | Inspect for poor connections at the harness connector of the headlamp switch assembly. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 18 | Go to Step 17
12 | Repair an open or high resistance in the ground circuit of the inoperative park lamp. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you complete the repair? | Go to Step 18 | --
13 | Repair an open or high resistance in the park lamp supply voltage circuit of the inoperative park lamp. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you complete the repair? | Go to Step 18 | --
14 | Repair an open or high resistance in the park lamp supply voltage circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you complete the repair? | Go to Step 18 | --
15 | Important: Perform the set up procedure for the BCM. Replace the BCM. Refer to Body Control Module Replacement in Body Control System. Did you complete the replacement? | Go to Step 18 | --
16 | Replace the auto park lamp control relay. Refer to Relay Replacement in Wiring Systems. Did you complete the replacement? | Go to Step 18 | --
17 | Replace the headlamp switch assembly. Refer to Headlamp Switch Replacement . 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 3