AUTOMATIC HEADLIGHT BEAM LEVEL CONTROL SYSTEM SYSTEM DESCRIPTION


  1. AUTOMATIC HEADLIGHT BEAM LEVEL CONTROL SYSTEM


    1. General


      • This system adjusts the headlight low beams when the vehicle is stopped to maintain a constant level.

      • This system is controlled by the headlight leveling ECU. This ECU detects the vehicle posture via the rear height control sensor, and detects the vehicle speed via the combination meter. The ECU then controls the headlight leveling motor based on these pieces of information in order to change the headlight reflector angle.

      Note


      • Initialize the height control sensor signal after the vehicle height changes due to replacement of the suspension or after performing such operations as removal and reinstallation or replacement of the rear height control sensor.

      • Initialization is also necessary when the headlight leveling ECU is replaced.

    2. Function and construction of components

      Component Outline
      Rear Height Control Sensor Detects the vehicle height.
      Combination Meter

      • Outputs the vehicle speed signal to the headlight leveling ECU.

      • Headlight beam level control system warning light in the combination meter illuminates for 3 seconds and then turns off when the ignition switch is turned to ON (bulb check function).

      • Headlight beam level control system warning light in the combination meter illuminates to alert the driver when a malfunction in this system is detected.
      Headlight Leveling Motor Based on the signals received from the headlight leveling ECU, each motor moves the reflector in the headlight to vary its low beam height.
      DLC3 The height control sensor signal initialization and headlight leveling motor operation check can be performed via the DLC3.
      Headlight Leveling ECU

      • Based on the signals that are transmitted by the rear height control sensor and combination meter, this ECU detects the amount of variance of the vehicle posture with the vehicle stopped.

      • Based on the detected value, this ECU outputs control signals to the headlight leveling motor.

      • This ECU turns on the headlight beam level control system warning light for 3 seconds when the ignition switch is turned to ON (bulb check function).

      • This ECU turns on the headlight beam level control system warning light to alert the driver when a malfunction in this system is detected.

    3. Fail-safe

      The headlight leveling ECU operates in fail-safe mode if an abnormal condition has been detected, and illuminates the automatic headlight beam level control system warning light in the combination meter when a malfunction is detected in the headlight beam level control system.