Automatic Headlamp Leveling Device Description and Operation

Description

Depending on driving conditions and vehicle load, the headlamp beam direction is adjusted so that the driver is not distracted by the visibility range and the driver's vision is protected from glare, allowing safe driving. The sensor mounted on the rear center link actuates the leveling actuator on the headlamp upon detecting an input signal following static changes in vehicle attitude. The headlamp beam is automatically adjusted when the chassis tilts. Purpose of AHLS (Automatic Headlamp Leveling System)

• Compensates headlamp visibility range when vehicle load changes.
• Prevents oncoming traffic from being dazzled by excessive glare.
• Meeting Position

Operation

Operating Procedure

1. 1
   Change in suspension angle due to change in vehicle load.
2. 2
   Height sensor signal change
3. 3
   Calculation of the HLLD signal by the AHLS ECU algorithm.
4. 4
   Sends the proper signal to the HLLD (headlamp leveling device) and actuator.
5. 5
   Activation of the HLLD and compensation of headlamp range.

Operating Condition

• IGN1 ON and low beam headlamps ON
• Sensor angle changed by more than 1° and held for 10~12 seconds with the vehicle stationary.
• Sensor angle changes by more than 1° and is maintained for 10~12 seconds, and when the vehicle is driven at a constant speed above 20 km/h.
• Leveling control is turned off after HLLD control for several seconds.
• To avoid mechanical tolerances, the lamp position is always reached from the lower side.

System Features

1. 1
   Height sensor and link.

   No.	Components
   1	Sensor Mounting Bracket
   2	Height Sensor and Link
   3	Link Bracket

   
   

   

   • Using the microprocessor, detect the mechanical change in the angle of the operating lever or the speed signal.
   • Acts as the actuator of the internal control program, installed on the rear center link.
2. 2
   HLLD (headlamp leveling device) actuator.

   

   • Changes the headlamp beam direction up or down, as the automatic headlamp leveling unit receives the input signal following static changes in vehicle attitude.