Step  | Action  | Yes  | No  | 
|---|---|---|---|
Schematic Reference: Exterior Lights Schematics Connector End View Reference: Lighting Systems Connector End Views or Data Communication Connector End Views  | |||
1  | Did you perform the Diagnostic System Check - Vehicle?  | Go to Step 2  | |
2  | Verify that the tail, marker and license lamps are inoperative. Do the tail, marker and license lamps operate normally?  | Go to Testing for Intermittent Conditions and Poor Connections  | Go to Step 3  | 
3  | 
 Was a ground signal present?  | Go to Step 8  | Go to Step 4  | 
4  | Use the scan tool to check the body control module (BCM) park lamp switch input data. Does the scan tool indicate a park lamps ON request signal?  | Go to Step 7  | Go to Step 5  | 
5  | Test for an open or high resistance in the park lamp switch signal circuit. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition?  | Go to Step 11  | Go to Step 6  | 
6  | Inspect for poor connections at the harness connector of the headlamp switch. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition?  | Go to Step 11  | Go to Step 9  | 
7  | Inspect for poor connections at the harness connector of the BCM. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition?  | Go to Step 11  | Go to Step 10  | 
8  | Replace the park lamp relay. Refer to Relay Replacement . Did you complete the repair?  | Go to Step 11  | --  | 
9  | Replace the headlamp switch. Refer to Headlamp Switch Replacement . Did you complete the repair?  | Go to Step 11  | --  | 
10  | Replace the BCM. Refer to Control Module References for replacement, setup, and programming. Did you complete the replacement?  | Go to Step 11  | --  | 
11  | Operate the system in order to verify the repair. Did you correct the condition?  | System OK  | Go to Step 3  |