Circuit Description

The PARK LP fuse and the HEADLAMP circuit breaker supply battery to the Daytime Running Lamps (DRL) control module. The DRL/HVAC TEMP fuse and the DRL fuse supply ignition positive voltage to the DRL control module. The Daytime Running Lamps (DRL) ambient light sensor is a light sensitive variable resister that varies its voltage signal to the DRL control module in response to changes to the outside or ambient light level. When the Daytime Running Lamps (DRL) ambient light sensor detects low light the DRL control module enter night mode. With the ignition switch in the RUN position, the headlamp switch placed in the OFF position, and the park brake OFF, the DRL control module operates the headlamps and parklamps when low light is detected. If the engine stalls with the DRL module in the low light mode, the DRL control module turns OFF the headlamps while the engine is being cranked. The DRL module will turn ON the side marker, park, license and taillamps while the engine is being cranked. Any function or condition that turns on the headlights will cancel the automatic headlamp operation.

When the Daytime Running Lamps (DRL) ambient light sensor detects daylight, the DRL control module will enter daytime mode. With the ignition switch in the RUN position, the headlamp switch placed in the OFF position, and the park brake OFF, the DRL control module operates the non flashing front turn signals when in daytime mode.