PRE-CRASH SAFETY SYSTEM SYSTEM DESCRIPTION


  1. PRE-CRASH SAFETY SYSTEM


    1. The pre-crash safety system optimizes and activates occupant protection equipment (see below) to attempt to reduce damage due to a collision.

  2. OUTLINE OF PRE-CRASH SAFETY SYSTEM

    Operating Condition Control Transmitting ECU Receiving ECU Part Operated
    Operates according to sensor detection Pre-crash seat belt Driving support ECU Seat belt control ECU Front seat outer belts
    Operates according to sensor detection Pre-crash brake assist Driving support ECU Skid control ECU assembly Brake assist system
    Operates when sudden braking occurs Pre-crash seat belt Skid control ECU assembly Seat belt control ECU Front seat outer belts
    Operates according to sensor detection Pre-crash brake Driving support ECU Skid control ECU assembly Brake system

    1. When operating according to sensor detection:

      The millimeter wave radar sensor detects vehicles and other objects on the road in front of the user's vehicle. The driving support ECU determines if a collision is unavoidable based on object position, speed and track information. If the driving support ECU determines that a collision is unavoidable, it transmits this information to the following areas using CAN communication:


      • Seat belt control ECU (initiates control of pre-crash seat belts)

      • Skid control ECU assembly (activates pre-crash brake assist system)

      • Skid control ECU assembly (activates pre-crash brake)

    2. When operating as a result of sudden braking:

      The skid control ECU assembly uses brake pressure information and other data to determine if the driver has suddenly applied the brakes. If so, the skid control ECU assembly sends a signal to the seat belt control ECU through CAN communication and the pre-crash seat belts activate.

  3. OUTLINE OF PRE-CRASH SEAT BELT CONTROL


    1. The pre-crash seat belts operate depending on what the sensor detects, or whether sudden braking has occurred. The pre-crash seat belt motor tightens the seat belt to optimize occupant restraint performance.

    2. Operative condition


      1. Refer to the sensor and sudden braking descriptions under "Outline of Pre-Crash Safety System" (see above).

  4. OUTLINE OF PRE-CRASH BRAKE ASSIST CONTROL


    1. The pre-crash brake assist operates depending on what the sensor detects. The system then enters standby mode before a collision. When the driver depresses the brake pedal, brake fluid pressure is increased to improve fluid pressure response and improve the rate of deceleration.

    2. Operative condition


      1. Refer to the sensor description under "Outline of Pre-Crash Safety System" (see above).

      2. When the driver depresses the brake pedal after the driving support ECU determines that a collision is unavoidable:

        Brake fluid pressure is increased at the same time the driver depresses the brake pedal.

      3. When the driver depresses the brake pedal before the driving support ECU determines that a collision is unavoidable:

        Brake fluid pressure is increased at the same time that the driving support ECU receives a pre-crash sensor signal (indicating that other vehicles or objects are in front of the vehicle).

  5. OPERATIVE CONDITION AND INOPERATIVE CONDITION OF EACH CONTROL (REVIEW)

    Pre-Crash Seat Belt*1 Pre-Crash Seat Belt*2 Pre-Crash Brake Assist*2 Pre-Crash Brake*2
    When the power switch is off or on (ACC) - - - -
    When a warning message is displayed on the multi-information display and/or headup display *3 *3 *3 *3
    When seat belt(s) is/are fastened *4 *4 ○ ○
    When the vehicle speed is 30 km/h (18 mph) or more, regardless of relative speed ○ - - -
    When the vehicle speed is 5 km/h (3 mph) or more and relative speed is 30 km/h (18 mph) - ○ - -
    When the vehicle speed is 15 km/h (9 mph) or more and relative speed is 15 km/h (9 mph) - - - ○
    When the vehicle speed is 30 km/h (18 mph) or more and relative speed is 30 km/h (18 mph) - - ○ -
    When the vehicle collides with an object outside the detection range of the millimeter wave radar sensor (side collision, rear collision, etc.) ○ - - -
    When the millimeter wave radar sensor cannot detect a possible collision object ○ - - -

    • *1: Operates when brakes are suddenly applied.

    • *2: Operates according to sensor detection.

    • *3: Inoperative parts are different depending on malfunction areas.

    • *4: Only operates when seat belt is fastened.

    • ○: Main basis for operation

    • -: Does not operate, or not main basis for operation

  6. PRECAUTION FOR PRE-CRASH SAFETY SYSTEM OPERATION


    1. When the millimeter wave radar sensor detects an object in front of the vehicle under the conditions described below, the driving support ECU may determine that a collision is unavoidable, and activate the pre-crash safety system. This activation of the system is not abnormal.

      A01NEWQE07

      Tech Tips


      • The pre-crash safety system will not activate when approaching safety cones or other plastic objects as they cannot be detected by the pre-crash sensor.

      • The pre-crash safety system may or may not activate when the pre-crash sensor detects the following objects: people, bicycles, motorcycles, trees, animals and snow fences.

        Object Type Example
        Objects that cannot be detected Plastic items (safety cones)
        Objects that cannot be detected in a stable manner People, bicycles, motorcycles, trees, animals, snow fences, etc.