Principles of Operation
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 state
- Headlamp switch position
- Headlamps on or off
- Transmission gear selection
On vehicles equipped with halogen headlamps, the BCM provides a pulse-width modulated voltage to the low beams (illuminating them at a reduced intensity) when the DRL is active.
On vehicles equipped with High Intensity Discharge (HID) headlamps, the BCM provides battery voltage to the front turn lamps (illuminating them at full intensity) when the DRL is active.
The Daytime Running Lamps (DRL) is not a programmable parameter for this vehicle.