Operation CHARM: Car repair manuals for everyone.

Exterior Headlamp Control

The headlamps and parklamps are illuminated via external relays which are controlled by the body controller module (BCM). When the parklamp switch is closed to ground the BCM grounds the parklamp relay coil which provides the power to the parklamps. This same parklamp power feed is also wired back into the BCM to provide the power feed for the PWM circuit. When the headlamp switch is closed to ground the BCM grounds both the low beam and high beam headlamp relays. The position of the hi-beam select switch will determine the mode of operation.

Note: On Chrysler vehicle line when the high beams are selected both high beams and low beams will be illuminated. Dodge and Plymouth vehicle lines support only one mode of operation at a time.