Motor, Headlamp Leveling: Operation

The controller board and logic circuitry of the headlight leveling motor controls motor operation based upon a voltage signal input received from the Instrument Panel Cluster (IPC) based upon manual inputs to the IPC through the headlight leveling push buttons integral to the IPC. The headlight leveling motors have a path to ground at all times. The motors operate only when the ignition switch and the headlight low beams are turned ON. When the motor is energized it will extend or retract the motor pushrod through an integral screw-drive transmission. The ball on the end of the pushrod is snapped into a socket clip on the back of the reflector within the upper front combination lamp unit housing, which will cause the reflector to move as the pushrod is extended or retracted, changing the angle at which the light is projected from the headlight.

The hardwired circuits for the headlight leveling motors may be diagnosed using conventional diagnostic tools and procedures. Refer to the appropriate wiring information. However, conventional diagnostic methods will not prove conclusive in the diagnosis of the active electronic elements within the headlight leveling motors or the IPC. The most reliable, efficient, and accurate means to diagnose the headlight leveling motor or the electronic controls and communication related to headlight leveling system operation requires the use of a diagnostic scan tool. Refer to the appropriate diagnostic information.