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:
Diagnosis system
1. CHECK DLC3
The vehicle's ECU uses ISO 15765-4 for
communication protocol. The terminal arrangement
of the DLC3 complies with SAE J1962 and matches
the ISO 15765-4 format.
NOTICE:
*: Before measuring the resistance, leave the
vehicle as is for at least 1 minute and do no ...
Precaution
1. INITIALIZATION
NOTICE:
Perform RESET MEMORY (AT initialization) when
replacing the automatic transaxle assembly, engine
assembly or ECM.
Perform REGISTRATION (VIN registration) when
replacing the ECM.
HINT:
Initialization cannot be completed by only removing the
batt ...
Inspection
1. INSPECT BRAKE DRUM INSIDE DIAMETER
(a) Using a brake drum gauge or equivalent, measure
the inside diameter of the drum.
Standard inside diameter:
254.0 mm (10.00 in.)
Maximum inside diameter:
256.0 mm (10.08 in.)
2. INSPECT REAR DRUM BRAKE SHOE LINING THICKNESS
(a) Using a ruler, ...
