Principles of Operation

Autolamps

Principles of Operation

The autolamp system:

- provides light sensitive on-off control of the lamps normally controlled by the headlamp switch.
- provides increased visibility for occupants when leaving the vehicle by keeping the lamps on for a preselected period of time after the ignition switch is turned OFF.
- uses a preselected time lapse that can be adjusted by the vehicle operator for up to a 3 minute delay.

The system consists of the following:

- Headlamp switch
- Light sensor
- Lighting Control Module (LCM)

For the autolamp system to be operational, the headlamp switch must be in the AUTOLAMPS ON position and the light sensor must always be exposed to outside light.

The system turns the exterior lamps on when the light available to the light sensor decreases below a predetermined level, such as at sunset. The lamps automatically turn off when the level of outside light exceeds a predetermined level, such as during daylight hours.

Placing the headlamp switch in any other position overrides the autolamps operation. Automatic operation is not possible until the headlamp switch is placed in the AUTOLAMPS ON position.

The autolamp time delay control defaults to 20 seconds unless changed by the operator. To change the time delay setting, refer to Autolamps Time Delay Adjustment Adjustments.

There is also a feature that turns on the exterior lamps when the windshield wipers are turned on. When the LCM detects a ground signal from the windshield wiper motor, the LCM turns the exterior lamps on. For diagnostics of the headlamps on with wipers on feature, refer to Wiper and Washer Systems.