Principles of Operation
WARNING: This page is about a different car, the 2012 Ford Pickup, 2012 Ford F550 Super Duty, 2012 Ford F450 Super Duty, and 2012 Ford Cab & Chassis. However, it is still accessible from the selected car via links, so may be relevant.
The Body Control Module (BCM) controls the Daytime Running Lamps (DRL) by using various inputs to determine whether or not the DRL should be illuminated. These inputs include:
- Ignition switch position
- Headlamp switch position
- Headlamps on or off
- Transmission gear selection (automatic transmission)
- Parking brake applied or released (manual transmission)
When the DRL is active, the BCM provides a pulse-width modulated voltage to the low beam headlamps. This illuminates the headlamps at a reduced intensity.
The BCM can be configured to turn the DRL on for this vehicle. Refer to MODULE CONFIGURATION for programmable parameter information.