TOYOTA PARKING ASSIST-SENSOR SYSTEM(for Hatchback) SYSTEM DESCRIPTION
GENERAL
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 an obstacle as well as their positions by indicating them on the multi-information display (in the combination meter assembly) and by sounding a buzzer.
FUNCTION OF COMPONENTS
Component
Function
No. 1 Ultrasonic Sensor
No. 2 Ultrasonic Sensor
No. 3 Ultrasonic Sensor
Detects the distance between the vehicle and an obstacle
No. 1 Clearance Warning Buzzer
No. 2 Clearance Warning Buzzer
Sounds to inform the driver according to the distance to an obstacle
Multi-information Display on Combination Meter Assembly
Displays the location of an obstacle and the approximate distance between the vehicle and the obstacle
Displays a malfunction of the ultrasonic sensor to inform the driver
Brake Actuator Assembly (Skid Control ECU)
Transmits the vehicle speed signal to the clearance warning ECU assembly
Back Sonar or Clearance Sonar Switch Assembly
Operating this switch enables, disables or cuts off the operation of the Toyota parking assist-sensor system
Clearance Warning ECU Assembly
Judges the approximate distance between the vehicle and an obstacle based on the signals from the ultrasonic sensors and sends it to the multi-information display
Sounds the buzzer
Main Body ECU (Multiplex Network Body ECU)
Transmits the parking brake signal to the clearance warning ECU assembly*1
Transmits the illumination signal to the clearance warning ECU assembly
Back-up Light Switch Assembly*1
Transmits the reverse signal to the clearance warning ECU assembly
ECM*2
Transmits the shift position signal to the clearance warning ECU assembly
Air Conditioning Amplifier Assembly
Transmits the temperature information to the clearance warning ECU assembly
*1: for EA66, EC60, EC61, EC65A or EC69
*2: for K311
OPERATION EXPLANATION
The operating conditions of each ultrasonic sensor differ according to the installation position as shown in the table below.
Installation Position
Operating Condition
Front
Ignition switch is ON.
Back sonar or clearance sonar switch assembly is on.
Parking brake is not applied*1
Shift lever is in any position other than R.*1
Shift lever is in any position other than P or R.*2
Vehicle speed is approximately 10 km/h (6 mph) or less.
Ignition switch is ON.
Back sonar or clearance sonar switch assembly is on.
Shift lever is in R.
Rear
Ignition switch is ON.
Back sonar or clearance sonar switch assembly is on.
Shift lever is in R.
*1: for EA66, EC60, EC61, EC65A or EC69
*2: for K311
When the system operates, the clearance warning ECU assembly transmits ultrasonic waves from the ultrasonic sensors. If these waves encounter an obstacle within one or more of the sensors ranges, the waves are reflected back to the sensors, which transmit them to the clearance warning ECU assembly.
Based on this information, the clearance warning ECU assembly sends signals to the multi-information display and the clearance warning buzzers. The approximate distance between the vehicle and the obstacle is then indicated, and the buzzer sounds.