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Test A: The High Beams Are Inoperative

PINPOINT TEST A: THE HIGH BEAMS ARE INOPERATIVE

Normal Operation
The lighting control module (LCM) and the multifunction switch are supplied voltage from the central junction box (CJB) through circuit 910 (PK). When the multifunction switch is placed in the FLASH-TO-PASS position, the voltage is routed to the LCM through circuit 12 (LG/BK). The LCM sends a 5-volt reference signal to the multifunction switch through circuit 12 (LG/BK). Ground is provided to the multifunction switch through circuit 57 (BK). When the multifunction switch is placed in the HIGH BEAM position, the signal is routed to ground. When the LCM detects ground or the higher voltage, the LCM provides voltage to the high beam headlamps.

This pinpoint test is intended to diagnose the following:
- Fuse
- Wiring, terminals or connectors
- Multifunction switch
- LCM


A1-A4:






A5-A7:






A7-A8: