Headlamp Alignment Actuator: Description and Operation

Dynamic Headlight Adjustment (DHL - Xenon Only)

Cars equipped with Xenon headlights require automatic headlight aim control; this necessitates a separate control module to carry out automatic adjustment of the headlights. With automatic headlight leveling, the load status and its changes are recorded by means of two height level sensors (potentiometers) located at the front and rear axles. The information from these sensors is communicated back to the DHL module.
Each headlight has electrically driven linear stepper motors, which are connected to the headlamp inserts in such a way that their movement changes the range of the headlamp.

DHL Headlight Adjustment Control Module is located under the dash on the drivers side.