Step  | Action  | Yes  | No  | 
|---|---|---|---|
Schematic Reference: Headlights/Daytime Running Lights (DRL) Schematics Connector End View Reference: Lighting Systems Connector End Views or Body Control System Connector End Views in Body Control System.  | |||
1  | Did you perform the Lighting System Diagnostic System Check?  | Go to Step 2  | |
2  | 
 Does the headlamp system operate normally?  | Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems  | Go to Step 3  | 
3  | Are both high and low beam headlamps inoperative?  | Go to Step 4  | Refer to Headlamps Inoperative - Low Beams or Headlamps Inoperative - High Beams  | 
4  | With a scan tool, observe the headlamp switch parameter. Does the scan tool indicate ACTIVE?  | Go to Step 7  | Go to Step 5  | 
5  | Connect a test lamp between the ground circuit of the headlamp switch connector and battery positive voltage. Does the test lamp illuminate?  | Go to Step 6  | Go to Step 9  | 
6  | Test the headlamps switch headlamps on signal circuit of the headlamp switch for a high resistance, an open, or a short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition?  | Go to Step 12  | Go to Step 8  | 
7  | Inspect for poor connections to 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 12  | Go to Step 10  | 
8  | Inspect for poor connections to the headlamp switch. 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 12  | Go to Step 11  | 
9  | Repair the ground circuit of the headlamp switch. Did you complete the repair?  | Go to Step 12  | --  | 
10  | 
 Important: Perform the setup procedure for the body control module. Replace the body control module. Refer to Body Control Module Replacement Did you complete the replacement?  | Go to Step 12  | --  | 
11  | Replace the headlamp switch. Refer to Headlamp Switch Replacement Did you complete the replacement?  | Go to Step 12  | --  | 
12  | Operate the system in order to verify the repair. Did you correct the condition?  | System OK  | Go to Step 3  |