POWER STEERING SYSTEM SYSTEM DESCRIPTION


  1. DESCRIPTION


    1. The power steering ECU (rack and pinion power steering gear assembly) generates the necessary steering assist torque by calculating the steering assist force and controlling the motor current, based on the steering torque information from the torque sensor (rack and pinion power steering gear assembly), vehicle speed information from the skid control ECU (brake actuator assembly), and information from the ECUs.

    2. When there is a drop in the power source voltage, the rear window defogger, windshield deicer, outer mirror heater, PTC heater and seat heater operations are limited as part of power steering system load control.

    3. When there is a drop in the power source that may require an increase in steering force, the system illuminates the power steering warning light in order to warn the driver.

    Function of Components:
    Component Function

    Rack and Pinion Power Steering Gear Assembly

    Tech Tips

    The components listed on the right are built-in

    		 Power Steering ECU

    • Calculates the motor operation current based on the steering torque and vehicle speed signals, and outputs it to the motor.

    • When a malfunction is detected in the power steering system, it outputs a warning signal to the combination meter assembly.
    Power Steering Motor

    • Generates power assist in accordance with the actuation current received from the power steering ECU.

    • The built-in motor rotation angle sensor detects the rotation angle of the motor.
    Torque Sensor Detects the steering torque.
    Reduction Mechanism Decelerates the motor rotation torque and transmits it to the rack shaft.
    Steering Sensor Detects the steering angle and steering direction.
    Skid Control ECU (Brake Actuator Assembly) Sends the vehicle speed signal and steering coordinated control amount signal to the rack and pinion power steering gear assembly.
    ECM Outputs the engine speed.
    Air Conditioning Amplifier Assembly Receives a signal from the power steering ECU (rack and pinion power steering gear assembly) to limit electrical usage.
    Combination Meter Assembly EPS Warning Light Illuminates to alert the driver when the power steering ECU (rack and pinion power steering gear assembly) detects a malfunction in the power steering system.
    Multi-information Display Displays a warning message to inform the driver of a malfunction in the system.
    Master Warning Light Illuminates when a warning message is displayed on the multi-information display.
    Multi Buzzer Sounds to warn the driver of a malfunction in the system.
    Forward Recognition Camera*1 Requests steering assist torque when the lane departure alert system judges that the vehicle is departing from its lane.
    Drive Mode Select Switch (Electric Parking Brake Switch Assembly)*2 Switches the driving mode.
    *1: w/ Forward Recognition Camera
    *2: w/ Drive Mode Select Switch