1999 Cadillac DeVille Owner's Manual - Page 106

yellowblue Light Sensor Exterior Lighting Battery Saver If the manual parking lamp control has been left on, the exterior lamps will turn off approximately 10 minutes after the ignition is turned to LOCK or ACCESSORY. This protects draining the battery in case you have accidentally left the headlamps or parking lamps on. If you need to purposely leave the lamps on for more than 10 minutes with the ignition in LOCK or ACCESSORY, turn the manual control knob off and then back on. To delay the lamps from turning off, see "Twilight Sentinel" in the Index. Interior Lamps Instrument Panel Intensity/Brightness Control The light sensor for the DRL and the Twilight Sentinel is located in the center of the front defogger grille. If you cover the sensor, it will read "dark" and the lamps will come on. The digital displays automatically dim when it becomes dark outside and your lights are on. When it's dark, the brightness control can be manually adjusted by turning the lamp control knob counterclockwise to dim and clockwise to brighten the lighting. The digital displays automatically brighten when it becomes light outside, although backlighting will remain active at the selected brightness as long as the lights are on. 2-46