LIGHTING SYSTEM


  1. FUNCTION OF MAIN COMPONENTS

    Component Function
    Headlight Leveling ECU Assembly

    • Detects changes of vehicle movement based on the signals from the rear height control sensor sub-assembly LH and vehicle speed signal.

    • Outputs control signals to the headlight leveling motors based on the detected value.

    • Provides initial set control and a fail-safe function.
    Headlight Leveling Motor LH/RH

    • Based on the signals received from the headlight leveling ECU assembly, each headlight leveling motor moves the projector unit in the headlight to vary its angle.

    • Each headlight leveling motor uses a stepper motor to precisely regulate the angle of the projector unit.

    Brake Actuator Assembly


    • Skid Control ECU

    		 Transmits the vehicle speed signal to the headlight leveling ECU assembly.
    Rear Height Control Sensor Sub-assembly LH Detects vehicle movement and transmits a signal to the headlight leveling ECU assembly.

    Headlight Dimmer Switch Assembly


    • Light Control Switch

    		 Transmits a light control signal to the main body ECU (multiplex network body ECU).
    Main Body ECU (Multiplex Network Body ECU) Receives a light control signal and transmits it to the headlight leveling ECU assembly.
    Combination Meter Assembly Displays a warning message on the multi-information display and sounds the buzzer to inform the driver when the headlight leveling ECU assembly detects a malfunction in this system.

  2. SYSTEM CONTROL


    1. The headlight leveling ECU assembly receives vehicle height change signals sent from the rear height control sensor sub-assembly LH and calculates the changes in the pitch angle of the vehicle. The headlight leveling ECU assembly drives the headlight leveling motor LH/RH in accordance with the change.

      Control Mode Details
      While Stopped If the vehicle attitude is stable for approximately 3 seconds with the headlights on while stopped, the headlight leveling ECU assembly operates the headlight leveling motor LH/RH in accordance with the detected change in vehicle attitude.

  3. FUNCTION


    1. The rear height control sensor sub-assembly LH detects the changes in vehicles rear ride height due to cargo loads etc., and operates the headlight leveling motor LH/RH in accordance with the changes, keeping the headlight axes at a constant angle.

  4. FAIL-SAFE


    1. When the headlight leveling ECU assembly detects a malfunction in the system, the system enters fail-safe mode as follows.

      Malfunctioning Parts Malfunction Detection Conditions Performed Control
      Excessively high input voltage The input voltage of the headlight leveling ECU assembly becomes 18.5 V or more. Control signal output to the headlight leveling motor LH/RH is stopped.
      Low input voltage The input voltage of the headlight leveling ECU assembly becomes 9 V or less.
      Rear height control sensor sub-assembly LH high input voltage The input voltage of the rear height control sensor sub-assembly LH becomes 6.25 V or more.
      Rear height control sensor sub-assembly LH low input voltage The input voltage of the rear height control sensor sub-assembly LH becomes 4.6 V or less.
      Rear height control sensor sub-assembly LH signal malfunction The signal voltage of the rear height control sensor sub-assembly LH becomes 4.75 V or more.
      The signal voltage of the rear height control sensor sub-assembly LH becomes 0.25 V or less.
      Headlight leveling ECU assembly malfunction The headlight leveling ECU assembly has a malfunction.
      CAN malfunction There is a malfunction in the data communication with the main body ECU (multiplex network body ECU) (headlight information). Control is continued.
      There is a malfunction in the data communication with the skid control ECU (brake actuator assembly) (vehicle speed signal). Control is continued assuming vehicle speed is 0 km/h (0 mph).