Principles of Operation

WARNING: This page is about a different car, the 2008 Ford RV Cutaway, 2008 Ford Econoline, 2008 Ford E450 Super Duty, and 2008 Ford Cutaway. However, it is still accessible from the selected car via links, so may be relevant.

The daytime running lamps (DRL) system operates the low beam headlamps at a reduced intensity. The DRL module supplies pulse width modulated (PWM) voltage to the low beam headlamps when the following conditions are met:

The high beam headlamps are not on
The ignition switch is in the RUN position

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