General Information

Automatic headlight beam adjustment On Board Diagnostic (OBD)

General note

Function
Automatic vertical headlight aim control keeps the tilt angle of switched on low beams constant, even when vehicle tilt is different due to a load
shift or acceleration/deceleration.

For the Automatic vertical headlight aim control, one level sensor at the front axle and one at the rear axle register the vehicle's spring deflection. A signal proportional to vehicle speed is also processed by the ABS control module.

The control module evaluate these signals and activate the automatic vertical headlight aim control actuators when the lights are switched on.

The automatic vertical headlight aim control consists of:
- Headlight range control module -J431-
- Left rear level control system sensor -G76-
- Left front level control system sensor -G78-
- Left headlight beam adjusting motor -V48-
- Right headlight beam adjusting motor -V49-

NOTE:
- Beside the control module identification, the Automatic vertical headlight aim control can also be recognized by a rapidly performed adjusting procedure of the headlights when switching on the ignition
- If malfunctions occur in the system, the driver is notified via a warning symbol in the instrument cluster's center display.