Toyota Sienna Service Manual: System description
1. DESCRIPTION OF OCCUPANT CLASSIFICATION SYSTEM
- GENERAL DESCRIPTION.
- In the occupant classification system, the occupant classification ECU calculates the weight of the occupant based on a signal from the occupant classification sensors. This system recognizes the occupant to be a child if it detects a weight of less than 36 kg (79.37 lb), and disables the front passenger airbag and front passenger side - side airbag.
- This system is mainly comprised of 4 occupant classification sensors that detect the load on the front passenger seat. The occupant classification ECU controls the system, and the passenger airbag ON/OFF indicator indicates the ON/OFF condition of the front passenger airbag and front passenger side - side airbag.
- OCCUPANT CLASSIFICATION SENSOR.
- The occupant classification sensors are installed on 4 brackets connecting the seat rail and seat frame. Accordingly, when load is applied to the front passenger seat by an occupant sitting in it, the occupant classification sensors register a distortion.
- DESCRIPTION FOR PASSENGER AIRBAG ON/OFF INDICATOR.
- The passenger airbag ON/OFF indicator is installed on the air conditioning control assembly. This indicator informs the driver whether the occupant classification ECU puts the front passenger airbag assembly and side airbag (front passenger side) into an active state or inactive state.
- If a malfunction occurs in the occupant classification system, "OFF" indication of the passenger airbag ON/OFF indicator and the SRS warning light will come on.
Precaution
1. INSPECTION PROCEDURE FOR VEHICLE INVOLVED
IN ACCIDENT
Perform the zero point calibration and sensitivity
check if any of the following conditions occur.
The occupant classi ...
How to proceed with
troubleshooting
The intelligent tester can be used in steps 4, 6, 8 and 9.
1 VEHICLE BROUGHT TO WORKSHOP
2 CUSTOMER PROBLEM ANALYSIS
3 PASSENGER AIRBAG ON/OFF INDICATOR CHECK
4 DTCs CHECK (Present and Past DTCs)
...
Other materials:
No. 1 Clearance Warning Buzzer Circuit
DESCRIPTION
The clearance warning ECU receives the ultrasonic sensor signal to sound the
front warning buzzer.
WIRING DIAGRAM
INSPECTION PROCEDURE
1 INSPECT FRONT BUZZER
Remove the clearance warning ECU with front buzzer.
Apply the battery voltage to the terminals 1 and 2 o ...
System check
HINT:
Performing a SYSTEM CHECK enables the system,
which consists of the multiple actuators, to be operated
without removing any parts. In addition, it can show
whether or not any DTCs are set, and can detect
potential malfunctions in the system. The SYSTEM
CHECK can be performed with an inte ...
Precaution
NOTICE:
Because the compressor operates at high voltages, wear
electric insulated gloves and pull out the service plug to
cut the high-voltage circuit before inspection.
1. DO NOT HANDLE REFRIGERANT IN AN ENCLOSED
AREA OR NEAR AN OPEN FLAME
2. ALWAYS WEAR EYE PROTECTION
3. BE CAREFUL NOT ...
