LIGHTING SYSTEM FAIL-SAFE CHART


  1. HID Headlight System

    The light control ECU operates in the fail-safe mode if an abnormal condition such as those listed below has been detected.

    Item Outline
    Detection of abnormal input voltage (High input voltage) If voltage that is input to the light control ECU is approximately 20 V or more, the ECU stops illuminating the headlights, and resumes when the voltage drops to 16 V or less.
    Detection of abnormal input voltage (Low input voltage) If voltage that is input to the light control ECU is 6 V or less, the ECU stops illuminating the low beam headlights, and resumes when the voltage becomes 10 V or more.

    Detection of abnormal output


    • Open in output side circuit

    • Short between output terminals

    • Short between output terminal and body ground

    		 If an abnormal condition occurs in the voltage that is output by the light control ECU, the ECU stops illuminating the low beam headlights and will maintain this state until the power is reinstated (by turning the light control switch from off to HEAD).
    Detection of bulb flashing If the bulb flashing repeats within approximately 5 seconds and continues for approximately 60 seconds, the light control ECU stops illuminating the low beam headlights and will maintain this state until the power is reinstated (by turning the light control switch from off to HEAD).
    Detection of abnormal light voltage (Low light voltage) After approximately 80 seconds since input voltage is supplied, if the light voltage is below approximately 31 V for approximately 0.5 seconds, the light control ECU stops illuminating the low beam headlights and will maintain this state until the power is reinstated (by turning the light control switch from off to HEAD).
    Detection of abnormal light voltage (High light voltage) If the light voltage is above approximately 69 V for approximately 0.5 seconds, the light control ECU stops illuminating the low beam headlights and will maintain this state until the power is reinstated (by turning the light control switch from off to HEAD)

  2. Automatic Headlight Beam Level Control System (w/ AFS)

    If the AFS ECU detects a malfunction in the automatic headlight beam level control system or intelligent AFS, it will take the actions indicated in the table below.

    Trouble Area

    Condition

    (Fail-safe Control for Automatic Headlight Beam Level Control)

    		 AFS OFF Indicator Light
    Headlight Swivel Motor Malfunction Continues control until a position that is 1° less than the current position is reached. Flash
    Steering Angle Sensor Signal Malfunction Continues control. Flash
    Speed Sensor Signal Malfunction

    • Continues to control using the normal speed sensor signal if one signal fails.

    • Judges that the vehicle speed is 0 km/h (0 mph) and continues to control if both speed sensor signals fail.

    		 Flash
    Height Control Sensor Signal Malfunction

    • Stops the operation after returning to the initial position (fail at higher than the initial position).

    • Stops the operation at the current position (fail at lower than the initial position).

    		 Flash
    Headlight Leveling Motor Malfunction

    Normal Side Headlight Leveling Motor


    • Stops the operation after returning to the initial position (fail at higher than the initial position).

    • Stops at the current position (fail at lower than the initial position).

    		 Flash

    Abnormal Side Headlight Leveling Motor


    • Stops at the current position.
    Communication Signal Malfunction

    Skid Control ECU:


    • Judges that the vehicle speed is 0 km/h (0 mph) and continues control.

    		 Flash

    Steering Angle Sensor:


    • Normally controls the system.

  3. Intelligent AFS

    If the AFS ECU detects a malfunction in the intelligent AFS or automatic headlight beam level control system, it will take the actions indicated in the table below.

    Trouble Area

    Condition

    (Fail-safe Control for Intelligent AFS Control)

    		 AFS OFF Indicator Light
    Headlight Swivel Motor

    Normal Side Headlight Swivel Motor:


    • Stops operating after returning to the initial position.

    		 Flash

    Abnormal Side Headlight Swivel Motor:


    • Stops at the current position.
    Steering Angle Sensor Signal Malfunction Stops operating after returning to the initial position. Flash
    Speed Sensor Signal Malfunction Stops operating after returning to the initial position. Flash
    Height Control Sensor Signal Malfunction Stops operating after returning to the initial position. Flash
    Headlight Leveling Motor Stops operating after returning to the initial position. Flash
    Communication Signal Malfunction

    Main Body ECU:


    • Stops operating after returning to the initial position.

    		 Flash

    ECM:


    • Stops operating after returning to the initial position.

    Skid Control ECU:


    • Stops operating after returning to the initial position.

    Steering Angle Sensor:


    • Stops operating after returning to the initial position.

  4. Automatic Light Control System

    If the main body ECU detects a malfunction in the automatic light control sensor, the main body ECU effects fail-safe control to prohibit the automatic light control. If the low beam headlights and taillights are on, the lights will remain on until the light control switch is turned off.

  5. Automatic Headlight Beam Level Control System (w/o AFS)


    1. The headlight leveling ECU operates in the fail-safe mode if an abnormal condition such as those listed below has been detected.

      Item Abnormality Detection Condition Return Condition Warning Indicator
      Height control sensor power source voltage Abnormal height control sensor power source voltage (4.6 V or less) is detected. Normal voltage is detected 50 times consecutively Illuminated
      Height control sensor signal voltage Abnormal height control sensor signal voltage (0.25 V or less, or 4.75 V or more) is detected.
      High power source voltage Abnormal high ignition voltage (18.5 V or more) is detected. Voltage of 17.5 V or less is detected Not illuminated
      Low power source voltage Abnormal low ignition voltage (9.0 V or less) is detected. Voltage of 9.3 V or more is detected for 0.1 second consecutively Not illuminated
      Vehicle speed Abnormal high speed of 180 km/h (113mph) or more is detected. Speed of less than 175 km/h (109 mph) is detected Not illuminated
      Reset while running Reset by a temporary blackout, etc. while running. Vehicle is stopped Not illuminated

  6. Automatic High Beam System


    1. The main body ECU (multiplex network body ECU) operates in fail-safe mode if an abnormal condition such as those listed below has been detected.

      Item Abnormality Detection Condition Return Condition Warning indicator
      Steering Angle Sensor Signal Malfunction Steering angle sensor malfunction is detected. Steering angle sensor malfunction is not detected, and engine switch is turned on (IG) again. Flashes
      Steering angle sensor zero point memory invalid is detected. Steering angle sensor zero point memory valid is detected. Not illuminated
      Steering angle sensor data continuity invalid is detected. Steering angle sensor data continuity invalid flag is detected. Not illuminated
      Speed Sensor Signal Malfunction Abnormal speed sensor signal is detected. Normal speed sensor signal is detected. Flashes
      CAN Communication Signal Malfunction Normal CAN communication signal is not detected consecutively. Normal CAN communication signal is detected. Flashes
      Automatic High Beam Sensor Communication stopped consecutively. Normal communication signal is detected. Flashes