Inspection and Verification (Start Testing Here)

1. Verify the customer's concern by operating the headlamp and autolamps system to duplicate the condition.
2. Inspect to determine if one of the electrical concerns apply:

Electrical
- Damaged light sensor amplifier.
- Damaged headlamp switch.
- Circuitry open/shorted.
- Open power distribution box HI-BEAM HEADLIGHTS Fuse (20 A).
- Open Fuse Junction Panel Fuse:
+ Fuse 4 (15 A).
+ Fuse 6 (15 A).
+ Fuse 8 (15 A).
+ Fuse 13 (15 A).
+ Circuit breaker 12 (20 A).

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 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 Lighting Control Module. If, after performing data link diagnostic test, the NGS Tester responds with NO RESPONSE/NOT EQUIPPED, go to Pinpoint Test AA. Test AA: No Communication With Lighting Control Module
5. If self test is passed and no DTCs are retrieved, go to the Symptom Chart to continue diagnostics. Symptom Chart(s)
6. If DTCs are retrieved, go to the Lighting Control Module DTC Index to continue diagnostics. Lighting Control Module Diagnostic Trouble Code Index
7. If the lighting control module cannot be accessed by the NGS Tester, go to Pinpoint Test AA. Test AA: No Communication With Lighting Control Module

Rotunda Service Bay Diagnostic System (SBDS (R)), 001-00001 may also be used to diagnose this system.