Inspection and Verification (Start Testing Here)

1. Verify the customer concern by operating the autolamps.
2. Visually inspect for obvious signs of mechanical and electrical damage; refer to the following chart:

VISUAL INSPECTION CHART

Mechanical
^ Headlamp switch
^ Autolamp switch
^ Autolamp sensor

Electrical
^ Blown fuse(s)
^ Damaged wiring harness
^ Headlamp bulb
^ Loose or corroded connection
^ Lighting Control Module (LCM)

3. If the inspection reveals obvious concern(s) that can be readily identified, repair as required.
4. If the concern remains after the inspection, connect the New Generation STAR (NGS) Tester to the Data Link Connector (DLC) located beneath the instrument panel and select the vehicle to be tested from the NGS menu. If the NGS does not communicate with the vehicle:
^ check that the program card is properly installed.
^ check the connections to the vehicle.
^ check the ignition switch position.
5. If the NGS still does not communicate with the vehicle, refer to the New Generation STAR Tester manual.
6. Perform the DATA LINK DIAGNOSTIC TEST. If the NGS responds with:
^ CKT914, CKT915 or CKT70 = ALL ECUS NO RESP/NOT EQUIP, refer to Information Bus.
^ NO RESP/NOT EQUIP for lighting control module (LCM), go to Pinpoint Test A. A No Communication/Unable to Perform Self-Test on LCM
^ SYSTEM PASSED, retrieve and record the continuous Diagnostic Trouble Codes (DTCs), erase the continuous DTCs and perform self-test diagnostics for the LCM.
7. If the DTCs retrieved are related to the concern, go to the LCM Diagnostic Trouble Code (DTC) Index Lighting Control Module Diagnostic Trouble Code Index to Continue diagnostics.
8. If no DTCs related to the concern are retrieved, Symptom Chart(s) to continue diagnostics.