Automatic Headlamp Leveling System (AHLS)

The SLMR and SLML use hardwired signals from the front and rear ride height sensors to calculate the pitching angle of the vehicle body from the axle positions. When equipped with an Air Suspension Control Module (ASCM) the SLMR and SLML will instead use bus signals from the Air Suspension Control Module (ASCM) to calculate the pitching angle of the vehicle body from the ride height sensors.

The BCM is used in the leveling system for gating messages between the ASCM, vehicle speed from the Brake System Control Module (BSCM), Powertrain Control Module (PCM) and the SLMs to support operation of the system.