PRE-CRASH SAFETY SYSTEM


  1. FUNCTION OF MAIN COMPONENTS

    Item Function
    Millimeter Wave Radar Sensor Assembly

    • Radiates millimeter radar waves forward, uses the reflected millimeter waves for detecting the presence of a preceding vehicle, the vehicle-to-vehicle distance, and the relative speed.

    • Determines whether a collision is unavoidable based on the information received from this sensor and the forward recognition camera. It then outputs a brake assist standby request signal and pre-crash brake request signal if required.
    Forward Recognition Camera

    • Detects preceding vehicle on the road ahead using image captured by the monocular camera and sends the information to the millimeter wave radar sensor assembly.

    • Transmits an operation signal to the camera heater.*1
    Camera Heater (Forward Recognition Hood)*1 The camera heater is heated according to signals from the forward recognition camera.
    Pre-crash Safety System Cancel Switch Assembly

    • Turn the pre-crash safety system on/off.

    • Switches between the 3 warning timings (Far, Middle and Near) when pressed.
    Brake Actuator Assembly Skid Control ECU

    • Receives a brake assist standby request signal from the millimeter wave radar sensor assembly, and switches the brake assist to standby mode. When a master cylinder pressure signal is input, it activates the brake assist.

    • Receives a pre-crash brake request signal from the millimeter wave radar sensor assembly, and then applies the brakes.

    • Transmits vehicle speed signals to the forward recognition camera and/or millimeter wave radar sensor assembly.
    Master Cylinder Pressure Sensor Detects the master cylinder pressure and transmits a signal to the skid control ECU.
    Pump Motor Receives an operation signal from the skid control ECU and generates hydraulic pressure for brake control.
    Combination Meter Assembly PCS Warning Light

    • Flashes or illuminates to warn the driver in accordance with signals from the millimeter wave radar sensor assembly.

    • Flashes when the system is malfunctioning.

    • Illuminates when the pre-crash safety system is not available due to certain reasons or when pre-crash brake and pre-crash brake assist operation are disabled using the VSC OFF switch.
    Master Warning Light Illuminates to warn the driver in accordance with signals from the millimeter wave radar sensor assembly.
    Multi-information Display Displays a warning message to inform or warn the driver of the system condition in accordance with signals from the millimeter wave radar sensor assembly.
    Multi Buzzer Sounds to warn the driver in accordance with signals from the millimeter wave radar sensor assembly when the system is malfunctioning.
    ECM Transmits an accelerator pedal position signal and shift position signal to the millimeter wave radar sensor assembly.
    Airbag Sensor Assembly Yawrate Sensor Detects the yaw rate and lateral/longitudinal deceleration of the vehicle and transmits the signal to the forward recognition camera and/or millimeter wave radar sensor assembly.
    Central Gateway ECU Relays and transmits each CAN communication data signal.
    Steering Sensor Detects the angle and direction of steering and transmits the signal to the millimeter wave radar sensor assembly.
    Stop Light Control Relay Illuminates the stop lights in accordance with the signals from the skid control ECU.
    Skid Control Buzzer Assembly Sounds to warn the driver in accordance with signals from the forward recognition camera.
    Speed Sensor Detects the wheel speed of each of the 4 wheels and transmits signals to the skid control ECU.
    Stop Light Switch Assembly Detects the depressing of the brake pedal and transmits the signals to the skid control ECU and millimeter wave radar sensor assembly.
    Accelerator Pedal Sensor Assembly Detects the amount of pedal effort applied to the accelerator pedal and transmits the signal to the ECM.
    Park/Neutral Position Switch Assembly*2 Transmits the shift position signal to the ECM.
    Back-up Light Switch Assembly*3 Transmits the on/off signal of the back-up light switch assembly to the combination meter assembly.
    VSC OFF Switch Disables the pre-crash brake and pre-crash brake assist operation when VSC OFF mode.

    *1: Models with camera heater

    *2: Models with automatic transmission

    *3: Models with manual transmission

  2. FUNCTION


    1. The pre-crash safety system uses a millimeter wave radar sensor and forward recognition camera to detect vehicle and pedestrians in front of your vehicle.

    2. When the system determines that the possibility of a frontal collision with a vehicle or pedestrian is high, a warning operates to urge the driver to take evasive action and the potential brake pressure is increased to help the driver avoid the collision.

    3. If the system determines that the possibility of a frontal collision with a vehicle or pedestrian is extremely high, the brakes are automatically applied to help avoid the collision or help reduce the impact of the collision.


      1. Pre-crash warning

        When the system determines that the possibility of a frontal collision is high, a buzzer will sound and a warning message will be displayed on the multi-information display to urge the driver to take evasive action.

      2. Pre-crash brake assist

        When the system determines that the possibility of a frontal collision is high, the system applies greater braking force in relation to how strongly the brake pedal is depressed.

      3. Pre-crash braking

        When the system determines that the possibility of a frontal collision is high, the system warns the driver. If the system determines that the possibility of a frontal collision is extremely high, the brakes are automatically applied to help avoid the collision or reduce the collision speed.

  3. OPERATING CONDITION


    1. The pre-crash safety system is enabled and the system determines that the possibility of a frontal collision with a vehicle or pedestrian is high. Each function is operational at the following speeds:


      1. Pre-crash warning:


        • Vehicle speed is between approximately 10 and 180 km/h(7 and 110 mph). (For detecting a pedestrian, vehicle speed is between approximately 10 and 80 km/h (7 and 50 mph). For detecting a stationary vehicle, vehicle speed is between approximately 10 and 90 km/h (7 and 55 mph).)

        • The relative speed between your vehicle and the vehicle or pedestrian ahead is approximately 10 km/h (7 mph) or more.

      2. Pre-crash brake assist:


        • Vehicle speed is between approximately 30 and 180 km/h (19 and 110 mph). (For detecting a pedestrian, vehicle speed is between approximately 30 and 80 km/h (19 and 50 mph). For detecting a stationary vehicle, vehicle speed is between approximately 30 and 90 km/h (19 and 55 mph).)

        • The relative speed between your vehicle and the vehicle or pedestrian ahead is approximately 30 km/h (19 mph) or more.

      3. Pre-crash braking:


        • Vehicle speed is between approximately 10 and 180 km/h (7 and 110 mph). (For detecting a pedestrian, vehicle speed is between approximately 10 and 80 km/h (7 and 50 mph). For detecting a stationary vehicle, vehicle speed is between approximately 10 and 90 km/h (7 and 55 mph).)

        • The relative speed between your vehicle and the vehicle or pedestrian ahead is approximately 10 km/h (7 mph) or more.

    2. The system may not operate in the following situations:


      1. If a battery terminal has been disconnected and reconnected, and then the vehicle has not been driven for a certain amount of time

      2. If the shift lever is in R

      3. If VSC is disabled (only the pre-crash warning function will be operational)

    3. Cancelation of the pre-crash braking


      1. If either of the following occur while the pre-crash braking function is operating, it will be canceled:


        • The accelerator pedal is depressed strongly.

        • The steering wheel is turned sharply or abruptly.

    4. Conditions under which the system may operate even if there is no possibility of a collision


      1. In some situations such as the following, the system may determine that there is a possibility of a frontal collision and operate.


        • When passing a vehicle or pedestrian

        • When changing lanes while overtaking a vehicle ahead

        • When overtaking a vehicle ahead that is changing lanes

        • When overtaking a vehicle ahead that is making a right/left turn

          B0020J0

        • When passing a vehicle in an oncoming lane that is stopped to make a left/right turn

          B0020KD

        • When driving on a road where relative location to a vehicle ahead in an adjacent lane may change, such as on a winding road

          B0020IO

        • When rapidly closing on a vehicle ahead.

        • If the front of the vehicle is raised or lowered, such as when the road surface is uneven or undulating

        • When approaching objects on the roadside, such as guardrails, utility poles, trees or walls

        • When there is a vehicle, pedestrian or object by the roadside at the entrance of a curve

          B0020IL

        • When driving on a narrow path surrounded by a structure, such as in a tunnel or on an iron bridge

        • When there is a metal object (manhole cover, steel plate, etc.), steps or a protrusion on the road surface or roadside

        • When a crossing pedestrian approaches very close to the vehicle

          B0020FP

        • When passing through a place with a low structure above the road (low ceiling, traffic sign, etc.)

          B0020OO

        • When passing under an object (billboard, etc.) at the top of an uphill road

          B0020I3

        • When rapidly closing on an electric toll gate barrier, parking area barrier or other barrier that opens and closes

        • When using an automatic car wash

        • When driving through or under objects that may contact the vehicles, such as thick grass, tree branches or a banner

          B0020OF

        • When the vehicle is hit by water, snow, dust, etc. from a vehicle ahead

        • When driving through steam or smoke

        • When there are patterns or paint on the road or a wall that may be mistaken for a vehicle or pedestrian

        • When driving near an object that reflects radio waves, such as a large truck or guardrail

        • When driving near a TV tower, broadcasting station, electric power plant, or other locations where strong radio waves or electrical noise may be present

  4. SYSTEM CONTROL


    1. Pre-crash Brake Assist


      1. When the driver depresses the brake pedal after the pre-crash safety system has determined that there is the possibility of a collision, brake fluid pressure is increased. If the possibility of a collision is still high, brake fluid pressure is further increased.

        B0020NEE05

    2. Pre-crash Braking


      1. When the pre-crash safety system determines high possibility of collision, the system performs pre-crash braking control.

        B0020LQE04

  5. DIAGNOSIS


    1. Initial Check


      1. The forward recognition camera and/or millimeter wave radar sensor assembly performs an initial check on the system for approximately 3 seconds after the ignition switch has been turned to ON.

    2. Monitor Function


      1. After completing the initial check, the pre-crash safety system becomes ready to operate. During this time, the forward recognition camera and/or millimeter wave radar sensor assembly periodically monitors the system for any malfunctions.

    3. Diagnostic Trouble Code (DTC)


      1. If the forward recognition camera and/or millimeter wave radar sensor assembly detects a malfunction in the pre-crash safety system, it stores a 5 digit Diagnostic Trouble Code (DTC) in memory.