Exterior Lighting Control

The BCM controls the following exterior lighting components:
^ The low beams and parklamps
^ The high beams
^ The daytime running lights
^ The park lamps
^ The foglamps

The DRLs operate the low beam headlamps at a reduced intensity when the
following conditions exist:
^ The vehicle is not in park
^ The park brake is not set
^ The normal headlamps are not ON

Automatic lighting control turns on the parklamps and headlamps when an ambient light sensor detects a low ambient light level. The system ensures that the headlamps/parklamps are ON if the driver is operating the vehicle after dark. When automatic lighting control is active, the headlamp dimmer switch determines whether high or low beams are selected.

If the ignition switch is turned to the ON position in a low ambient light level area, automatic lighting control becomes active immediately, otherwise 8 seconds must elapse before the automatic lighting control is activated. If the park brake is set when the ignition switch is turned to ON, the automatic lighting control will be disabled until the park brake is released. If the automatic lighting control is active and a high ambient light level is detected, 20 seconds must elapse before the automatic lighting control is turned OFF. The headlamps are disabled during engine crank.

The foglamp control system will activate the foglamp relay under the following conditions:
^ The ignition switch is in the ON position.
^ The parklamps are active.
^ The high beam headlamps are OFF.
^ The foglamps switch is ON.

High beams ON and the parklamps ON are used to disable the foglamp relay output as required. The backup lamps are the only exterior lamps that are not controlled by the BCM.