With GEM

1. The interior lighting system is a Generic Electronic Module (GEM)/Central Timer Module (CTM) controlled system.
2. Verify the customer concern by operating the interior lamps.
3. Visually inspect for obvious signs of mechanical and electrical damage.

VISUAL INSPECTION CHART

Mechanical
^ Switch(es)

Electrical
^ Fuse(s)
^ Wiring harness
^ Loose or corroded connector(s)
^ Circuitry open/shorted
^ Bulb(s)

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 NGS Tester responds with:
^ CKT914, CKT915 or CKT70 = ALL ECUS NO RESP/NOT EQUIP, REFER to Information Bus.
^ NO RESP/NOT EQUIP for GEM, go to Pinpoint Test J. Test J : No Communication With the Module - GEM
^ NO RESP/NOT EQUIP for RAP, go to Pinpoint Test K. Test K : No Communication W/Module - Remote A-Theft Personality
^ SYSTEM PASSED, retrieve and record the continuous Diagnostic Trouble Codes (DTCs), erase the continuous DTCs and perform self-test diagnostics for the GEM and the Remote Anti-theft Personality (RAP) module.

7. If the DTCs retrieved are related to the concern, GO to the GEM or RAP Module Diagnostic Trouble Code Index. With GEM
8. If no DTCs related to the concern are retrieved, proceed to Symptom Chart - GEM. With GEM