Toyota Parking Assist-Sensor System System Description

Body Electrical. Camry. Acv40 Gsv40
Park Assist Monitoring. Camry. Acv40 Gsv40

  1. GENERAL

  1. FUNCTION OF COMPONENTS

  1. OPERATION EXPLANATION

Toyota Parking Assist-Sensor System -- System Description



GENERAL

  1. This system uses ultrasonic sensors to detect any obstacles at the corners and the rear of the vehicle. The system then informs the driver of the distance between the sensors and the obstacles as well as their position by sounding a buzzer.


FUNCTION OF COMPONENTS

Component
Function
Ultrasonic Sensor
Consists of a sensor portion that transmits and receives ultrasonic waves and a pre-amplifier that amplifies them. The ultrasonic sensor outputs the ultrasonic transmission and reception signals to the clearance warning ECU.
Clearance Sonar Main Switch
Turns the Toyota parking assist-sensor system on and off.
Clearance Warning Buzzer (for Corner Sensors)
  1. Emits an intermittent sound to inform the driver that the ECU has detected an obstacle within the predetermined ranges.
  2. If a corner sensor circuit malfunctions, the clearance warning buzzer receives a buzzer request signal from the clearance warning ECU. The signal causes the buzzer to emit a specific intermittent sound to inform the driver of the malfunction. The intermittent sound indicates the position of the malfunctioning corner sensor circuit.
Clearance Warning Buzzer (for Back Sensors)
  1. Emits an intermittent sound to inform the driver that the ECU has detected an obstacle within the predetermined ranges.
  2. If a back sensor circuit malfunctions, the clearance warning buzzer receives a buzzer request signal from the clearance warning ECU. The signal causes the buzzer to emit a specific intermittent sound to inform the driver of the malfunction. The intermittent sound indicates the position of the malfunctioning back sensor circuit.
Clearance Warning ECU
  1. Operates when an on signal is received from the clearance sonar main switch.
  2. Judges the approximate distance between the vehicle and an obstacle based on signals from the ultrasonic sensors. When it has detected an obstacle, it sends a buzzer request signal to the clearance warning buzzer (for corner sensors) or clearance warning buzzer (for back sensors) depending on the position of the ultrasonic sensor that is detecting the obstacle.
  3. Sends a buzzer request signal when a malfunction is detected in a corner sensor circuit or the back sensor circuit. The buzzer request signal that is sent to the clearance warning buzzer (for corner sensors) or clearance warning buzzer (for back sensors) depends on the location of the malfunctioning sensor circuit.
  4. Turns the corner sensors on or off according to the vehicle speed signal received from the combination meter assembly.
  5. Turns the back sensors on or off according to the reverse signal received from the park/neutral position switch (for A/T) or back-up light switch (for M/T).
  6. Turns the corner sensors on or off according to the parking brake condition received from the parking brake switch.
  7. Switches the size of the short detection range according to the condition of the back sensor detection range switching connector.
Combination Meter Assembly
Sends the vehicle speed signal to the clearance warning ECU.
Park/Neutral Position Switch (for A/T)
Sends the reverse signal to the clearance warning ECU when the shift lever is moved to R.
Back-up Light Switch (for M/T)
Sends the reverse signal to the clearance warning ECU when the shift lever is moved to R.
Parking Brake Switch
Sends the parking brake condition to the clearance warning ECU.
Back Sensor Detection Range Switching Connector
The back sensor detection range switching connector condition is detected by the clearance warning ECU.

OPERATION EXPLANATION

  1. The operating conditions of each ultrasonic sensor differ according to its installed position as shown in the table below:

    Sensor
    		Operating Condition
    Front Corner Sensor
    1. Ignition switch is ON.
    2. Clearance sonar main switch is ON.
    3. Parking brake is OFF.
    4. Vehicle speed is approx. 10 km/h (6.2 mph) or less. The sensor stops operating when the vehicle speed exceeds 15 km/h (9.3 mph), and starts operating when the vehicle speed drops to below 10 km/h (6.2 mph).
    Rear Corner Sensor
    1. Ignition switch is ON.
    2. Clearance sonar main switch is ON.
    3. Parking brake is OFF.
    4. Vehicle speed is approx. 10 km/h (6.2 mph) or less. The sensor stops operating when the vehicle speed exceeds 15 km/h (9.3 mph), and starts operating when the vehicle speed drops to below 10 km/h (6.2 mph).
    Rear Center Sensor
    1. Ignition switch is ON.
    2. Clearance sonar main switch is ON.
    3. Shift lever is in R.
    When the system operates, the clearance warning ECU transmits ultrasonic waves from the ultrasonic sensors. If these waves encounter an obstacle within one or more of the sensor ranges, the waves are reflected back to the sensors, which transmit them to the clearance warning ECU.
    Based on this information, the clearance warning ECU sends signals to the clearance warning buzzer.

    HINT:
    1. When two or more ultrasonic sensors for the corner detect obstacles, the clearance warning buzzer sounds based on the closest sensor to the obstacle.
    2. Refer to Operation Check for detailed operation (Link).