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 park, license and tail lamps are inoperative. Do the park, license and tail lamps operate normally?  | Go to Testing for Intermittent Conditions and Poor Connections  | Go to Step 3  | 
3  | Are all park, license, and tail lamps inoperative?  | Go to Step 6  | Go to Step 4  | 
4  | Test the supply circuit of the inoperative lamp for high resistance or an open. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition?  | Go to Step 15  | Go to Step 5  | 
5  | Test the ground circuit of the inoperative lamp for high resistance or an open. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition?  | Go to Step 15  | Go to Step 11  | 
6  | 
 Does the scan tool display On?  | Go to Step 12  | Go to Step 7  | 
7  | Use the scan tool to monitor the BCM park lamp switch input data. Does the scan tool display Active?  | Go to Step 10  | Go to Step 8  | 
8  | 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 15  | Go to Step 9  | 
9  | Inspect for poor connections at the harness connector of the headlamp switch. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs . Did you find and correct the condition?  | Go to Step 15  | Go to Step 13  | 
10  | Inspect for poor connections at the harness connector of the BCM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs . Did you find and correct the condition?  | Go to Step 15  | Go to Step 14  | 
11  | Replace the inoperative bulb. Did you complete the replacement?  | Go to Step 15  | --  | 
12  | Replace the park lamp relay. Refer to Relay Replacement . Did you complete the repair?  | Go to Step 15  | --  | 
13  | Replace the headlamp switch. Refer to Headlamp Switch Replacement . Did you complete the repair?  | Go to Step 15  | --  | 
14  | Replace the BCM. Refer to Control Module References for replacement, setup, and programming. Did you complete the replacement?  | Go to Step 15  | --  | 
15  | Operate the system in order to verify the repair. Did you correct the condition?  | System OK  | Go to Step 3  |