Adaptive Front Lighting System

System Description

The adaptive front lighting control system consists of the adaptive front lighting control unit, suspension stroke sensor, steering angle sensor, headlight leveling motors, adaptive front lighting gearbox, AFS indicator in the gauge, and AFS OFF switch. The function of the system is to adjust the headlights for best aiming of the headlight beams. The suspension stroke motors move the headlight aiming up and down, and the adaptive front lighting gearbox moves the headlight aiming left and right. The suspension stroke sensor sends signals regarding vertical movement via the control unit to the headlight leveling motors, and the steering angle sensor and vehicle speed pulse send signals regarding horizontal movement via the control unit to the adaptive front lighting gearboxes. Also the control unit has a self-diagnostic function and fail-safe function.

Swivel Control

The headlight swivel angle is controlled by the signals from the steering angle sensor. The swivel control starts when the conditions shown are satisfied.
- Headlight switch is ON.
- AFS OFF switch is not pressed.
- Vehicle speed is over 5 mph (8 km/h).




Initialize function

When the headlight switch is ON, the swivel angle is initialized every time in spite of the ignition switch ON (II) or OFF. The right headlight aiming moves right 22.2 degree and the left headlight aiming moves right 0.8 degree, then returns the headlight aiming to center and complete the initialization.

Leveling Control

The headlight leveling is controlled by the signals from the suspension stroke sensor. The leveling control starts when both the ignition switch and headlight switch are ON.

Fail-safe Function

If a malfunction occurs to any of sensors, B-CAN line or control unit, the adaptive front lighting control system moves to fail-safe mode. In this case, the system stops control and the AFS indicator in the gauge blinks to show the malfunction. If the swivel control has a malfunction, the headlight aiming stays centered. If the leveling control has a malfunction, the headlight aiming stays at 0.6 degree under the present position.