Initial Inspection and Diagnostic Overview

1. The interior lighting system is controlled by a Generic Electronic Module (GEM). Refer to Multifunction electronic Control Module.
2. Verify the customer concern by operating the interior lamps.
3. Visually inspect for obvious signs of mechanical and electrical damage.







VISUAL INSPECTION CHART

4. If the concern remains after the inspection, connect the scan tool to the Data Link Connector (DLC) located beneath the instrument panel and select the vehicle to be tested from the scan tool menu. If the scan tool 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 scan tool still does not communicate with the vehicle, refer to the scan tool manual.
6. Perform the DATA LINK DIAGNOSTIC TEST. If the scan tool responds with:
^ CKT914, CKT915 or CKT70 = ALL ECUS NO RESP/NOT EQUIP, refer to Module Communications Network.
^ NO RESPONSE/NOT EQUIPPED for generic electronic module (GEM), go to Pinpoint Test K. Test K: Turn Signal Lamps Are Never on
^ SYSTEM PASSED, retrieve and record the continuous Diagnostic Trouble Codes (DTCs), erase the continuous DTCs and perform self-test diagnostics for the GEM.

7. If the DTCs retrieved are related to the concern, go to the GEM Diagnostic Trouble Code (DTC) Index to continue diagnostics. Diagnostic Trouble Code Tests and Associated Procedures
8. If no DTCs related to the concern are retrieved, proceed to Symptom Chart to continue diagnostics. Symptom Related Diagnostic Procedures