Test A: The High Beams Are Inoperative

PINPOINT TEST A: THE HIGH BEAMS ARE INOPERATIVE

NOTE: If only the flash-to-pass is inoperative, GO to Pinpoint Test E. Test E: The Flash-To-Pass Feature Is 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 multifunction switch is placed in the FLASH-TO-PASS position, the voltage is routed to the LCM through circuit 12 (LG/BK). When the LCM detects ground or the higher voltage, the LCM provides voltage to the high beam headlamps. The LCM uses voltage from circuit 910 (PK) to provide voltage to the high beams.

For police interceptor vehicles, when the driver door module (DDM) receives a ground signal from the wig-wag module, the DDM sends a message to the LCM to disable the high beams.

DTC B1153 (Police Wigwag Lighting Input Circuit Short to Ground) - sets when the DDM detects a short to ground from the wig-wag module input.

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

A1-A3:

A3-A6:

A6-A8:

A9-A10: