Principles of Operation

The autolamp system provides light-sensitive automatic ON/OFF control of the headlamps and parking lamps controlled by the vehicle security module when the headlamp switch is in the AUTOLAMP position. When the ignition switch is turned to the RUN or START position with the autolamps feature already enabled and the ambient light level is dark, the vehicle security module requests the headlamps and parking lamps turned on. When the autolamps are disabled, the vehicle security module request the headlamps and parking lamps turned off, regardless of the ignition switch position. When the vehicle security module has turned on the exterior lamps and the ignition is turned to the OFF or ACCY position, the exterior lamps will remain on for an additional 20 seconds.

When the autolamps have been enabled and the ignition switch is in the RUN/START position, the vehicle security module requests that the exterior lamps turned on or off based on ambient light level. If the vehicle enters darkness for at least 15 seconds, the vehicle security module requests the exterior lamps on. If the vehicle enters light for at least 15 seconds, the vehicle security module requests the exterior lamps off. By delaying turning on and off the exterior lamps during short periods of darkness and light, the vehicle security module prevents the exterior lamps from flashing on and off.