Operation CHARM: Car repair manuals for everyone.

Principles of Operation

PRINCIPLES OF OPERATION

The daytime running lamps (DRL) are implemented by using the low beams at a reduced voltage of approximately 80% system voltage. This is accomplished by inserting a resistor in series with the low beam filaments. When the headlamp switch is engaged, the daytime running lamp function is disabled and the low beam filaments receive 100% system voltage.