Clearance Sonar System

System Diagram:

SYSTEM DESCRIPTION

1. GENERAL
This system uses ultrasonic sensors to detect any obstacles at the corners, the front or the rear of the vehicle. The system then informs the driver of the distance between the sensors and the obstacles, as well as their positions by displaying them on the multi-information display in the combination meter and by sounding a buzzer. This information also appears on the multi-display on the models equipped with a LEXUS navigation system.




2. FUNCTIONS OF COMPONENTS

3. OPERATION EXPLANATION
a. The clearance warning ECU assembly determines whether the clearance sonar system should be operated or not based on the clearance sonar main switch, the shift position, the vehicle speed and the engine speed signals.
b. When the system operates, the clearance warning ECU transmits ultrasonic waves from the ultrasonic sensor. If these waves encounter an obstacle within the sensor's range, the waves are reflected back to the sensor, which transmits them to the clearance warning ECU assembly.

Based on this information, the clearance warning ECU assembly sends signals to the multi-information display, the multi-display and the clearance warning buzzer. The appropriate distance between the vehicle and the obstacle is then displayed, and the buzzer sounds.

HINT: Refer to "OPERATION CHECK" for detailed operation.