Principles of Operation

Automatic illumination
The autolamps operation is an integral function of the Lighting Control Module (LCM). When the ignition switch is in the ON position, power is supplied through fuse junction panel F35 (10A) to the LCM. The LCM receives ambient light intensity status from the autolamp sensor (located in the instrument panel defroster opening grille near the windshield) to determine whether to illuminate the headlamps. Depending on the multifunction switch position, the LCM may illuminate either the low beam headlamps or the high beam headlamps.

During an autolamp automatic illumination event, the tail lamp relay (located in the fuse junction panel) is enabled by the LCM to illuminate the parking, license and rear lamps.

Autolamps - Shut-Off Delay
When the headlamps are in autolamp mode and the ignition switch is turned to the OFF position, a timer (integral to the LCM) will be started. Depending on the autolamp switch (Position 1 or Position 2), the headlamps will continue to illuminate for a length of time until the timer reaches the end of its cycle. Position 1 will illuminate the headlamps for approximately 25 seconds and Position 2 will illuminate the headlamps for approximately 3 minutes. The LCM will deenergize the tail lamp relay at the time the ignition switch in placed in the OFF position.