Flow of Diagnosis

1. Verify the customer's concern by operating the switches to duplicate the condition.
^ In RUN without the engine running.
^ In START before the ignition switch is released.
^ In RUN with the engine running.
2. Inspect to determine if any of the following mechanical or electrical concerns apply:
^ Mechanical
- Damaged switch.
- Low fluid level (washer system).
^ Electrical
- Fuse.
- Circuit wiring.
- Switches or sending units.
3. If inspection reveals an obvious concern that is readily serviced, correct the concern before continuing with Inspection and Verification.
4. If a concern remains after the inspection, use the Rotunda New Generation Star (NGS) Tester 007-00500 or equivalent, connected to the data link connector (DLC) to retrieve continuous diagnostic trouble codes (DTCs) and to execute Self Test Diagnostics for the generic electronic module. If after performing data link diagnostic test, NGS responds with module NO RESPONSE/NOT EQUIPPED, go to Pinpoint Test A. Pinpoint Test A - No Communications With GEM
5. If self test is passed and no DTCs are retrieved, go to the Symptom Chart to continue diagnostics. Symptom Chart - Electrical
6. If DTCs are retrieved go to the Generic Electronic Module (GEM) DTC Index to continue diagnostics. Diagnostic Trouble Code Tests and Associated Procedures
7. If the generic electronic module cannot be accessed by the NGS, go to Pinpoint Test A. Pinpoint Test A - No Communications With GEM