Module, Automatic Headlamp Leveling (AHLM): Description

Vehicles equipped with the optional headlamp leveling system are also equipped with an (Automatic Headlamp Leveling Module) AHLM. The AHLM is attached to the passenger headlamp assembly.

This module works in conjunction with the front and rear axle (leveling) sensors, the headlamp leveling motors, the headlamp swiveling motors and electronic message inputs received over the Controller Area Network (CAN) data bus from other electronic modules in the vehicle. The module provides automatic headlamp beam aim adjustment to compensate for changes in vehicle height or direction caused by changes in vehicle loading, acceleration, deceleration, steering wheel angle and YAW rate.

Concealed within the module housing is the circuitry of the module itself, which includes a microcontroller. The module is connected to the vehicle electrical system through an integral connector receptacle by a take out and connector of the headlamp and dash wire harness.

The AHLM module cannot be adjusted or repaired and, if ineffective or damaged, it must be replaced. The AHLM module is Flash programmable.