Toyota RAV4 manuals

Toyota Sienna Service Manual: System description

1. 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 positions by indicating them on the clearance sonar display and by sounding a buzzer.

2. FUNCTIONS OF COMPONENTS

Components

Function

Ultrasonic Sensor Ultrasonic sensor consists of a sensor portion that transmits and receives ultrasonic waves and a pre-amplifier that amplifies the waves. The ultrasonic sensor outputs the ultrasonic transmission and reception signals to the clearance warning ECU.
Clearance Sonar Main Switch Turns the clearance sonar system on and off.
Clearance Warning Buzzer Emits an intermittent sound to inform the driver that the ECU has detected an obstacle within prescribed ranges.
Clearance Warning ECU Judges the approximate distance between the vehicle and the obstacle based on the signals from the ultrasonic sensors and sends the display signal to the clearance sonar indicator and the buzzer signal to the clearance warning buzzer.
Indicators Displays the location of the obstacle and the approximate distance between the vehicle and the obstacle.
Speed Sensor Detects speed of each wheel and inputs the data into the clearance warning ECU via the combination meter.
Park / Neutral Position Switch (A/T) Sends a signal that activates the clearance sonar system when the shift lever is moved to the R position.

3. OPERATION EXPLANATION

  1.  The clearance warning ECU determines whether the clearance sonar system should be operated based on the clearance sonar main switch on/off stratus, the shift position and the vehicle speed.
  2.  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 sensors' 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 indicator and the clearance warning buzzer. The approximate distance between the vehicle and the obstacle is then indicated, and the buzzer sounds.

HINT: Refer to "OPERATION CHECK" for detailed operation

Parts location
SYSTEM DIAGRAM ...

How to proceed with troubleshooting
1 VEHICLE BROUGHT TO WORKSHOP 2 CUSTOMER PROBLEM ANALYSIS 3 CHECK INITIAL CHECK FUNCTION 4 PROBLEM SYMPTOMS TABLE THE CORRESPONDING SYSTEM DOES NOT EXIST (Go to step 5) 5 BASED ON THE MALFUNCTION ...

Other materials:

DVD Error/ Excess Current/ Tray Insertion / Ejection Error
DTC 44-44 DVD Error DTC 44-48 Excess Current DTC 44-50 Tray Insertion / Ejection Error DESCRIPTION DTC No. DTC Detecting Condition Trouble Area 44-44 Operation error in the DVD mechanism. Television display assembly 44-48 Excess current is ...

Fuel Pump Primary Circuit
DESCRIPTION This DTC is designed to detect a malfunction in the fuel pump (FUEL PUMP) relay circuit. When the system is normal, the battery voltage is applied to FPR terminal of the ECM while the FUEL PUMP relay is turned OFF. If the battery voltage is not applied to the FPR ter ...

CD Abnormal/ Excess Current/ Tray Insertion / Ejection Error
DTC 63-44 CD Abnormal DTC 63-48 Excess Current DTC 63-50 Tray Insertion / Ejection Error DESCRIPTION DTC No. DTC Detection Condition Trouble Area 63-44 Operation error in the CD mechanism Radio and navigation assembly 63-48 Excess current is pr ...

© 2011-2025 Copyright www.tsienna.net