Principles of Operation (How Does It Work?)

The Daytime Running Lamps (DRL) system operates the low beam headlamps at a reduced intensity. The DRL module supplies Pulse Width Modulated (PWM) voltage, approximately 75-92% of battery voltage, to the low beam headlamps when the following conditions are met:
^ The parking brake control is released.
^ The high beam headlamps are disabled.
^ The ignition switch is in the RUN position.

The DRL module remains enabled when the low beam headlamps are turned on.