Toyota Sienna Service Manual: Occupant Classification ECU Malfunction
DTC B1795 Occupant Classification ECU Malfunction
DESCRIPTION
DTC B1795 is recorded when a malfunction is detected in the occupant classification ECU.
Troubleshoot DTC B1771 first when the DTCs B1771 and B1795 are output simultaneously.
WIRING DIAGRAM
INSPECTION PROCEDURE
1 CHECK DTC
- Turn the ignition switch to the ON position, and wait for at least 10 seconds.
- Check the DTCs.
Result:
A: DTC B1795 is output.
B: DTCs B1771 and B1795 are output.
HINT: Codes other than DTC B1771 and B1795 may be output at this time, but they are not related to this check.
2 CHECK FUSE
- Measure the resistance of the ECU-B fuse.
Resistance: Below 1 Ω
3 CHECK WIRE HARNESS (SOURCE VOLTAGE)
- Turn the ignition switch to the LOCK position.
- Disconnect the negative (-) terminal cable from the battery, and wait for at least 90 seconds
- Disconnect the connector from the occupant classification ECU.
- Connect the negative (-) terminal cable to the battery.
- Turn the ignition switch to the ON position.
- Measure the voltage according to the value(s) in the table below.
Standard voltage
- Turn the ignition switch to the LOCK position.
- Measure the resistance according to the value(s) in the table below.
Standard resistance
4 REPLACE OCCUPANT CLASSIFICATION ECU
- Turn the ignition switch to the LOCK position.
- Disconnect the negative (-) terminal cable from the battery, and wait for at least 90 seconds.
- Replace the occupant classification ECU
5 PERFORM ZERO POINT CALIBRATION
- Connect the negative (-) terminal cable to the battery.
- Connect the intelligent tester to the DLC3.
- Turn the ignition switch to the ON position.
- Using the intelligent tester, perform "Zero point calibration".
OK: "COMPLETED" is displayed.
6 PERFORM SENSITIVITY CHECK
- Using the intelligent tester, perform "Sensitivity check".
Standard value: 27 to 33 kg (59.52 to 72.75 lb)
END
Open in Occupant Classification ECU Battery
Positive Line
DTC B1794 Open in Occupant Classification ECU Battery
Positive Line
DESCRIPTION
This circuit consists of the occupant classification ECU and the power source
circuit (battery, fuse, wire
harness ...
Sleep Operation Failure of Occupant Classification
ECU
DTC B1796 Sleep Operation Failure of Occupant Classification
ECU
DESCRIPTION
During sleep mode, the occupant classification ECU reads the condition of
each sensor while the ignition
switch is of ...
Other materials:
Removal
HINT:
Remove the RH side by same procedures with LH side.
1. REMOVE FRONT WHEEL
2. REMOVE FRONT FENDER LINER LH
3. REMOVE FRONT SPEED SENSOR LH
(a) Disconnect the speed sensor connector.
(b) Remove the sensor harness and clamp from the
body.
(c) Remove the 2 clamp bolts holding the ...
Terminals of ECU
1. CHECK INSTRUMENT PANEL J/B ASSEMBLY
(MULTIPLEX NETWORK BODY ECU)
Disconnect the B6, B7 and B9 ECU connectors.
Disconnect the 1A, 1C, 1L and 1K J/B connectors.
Measure the voltage and resistance between each
terminal of the wire harness side connectors and
body gro ...
Unlock warning switch
INSPECTION
1. INSPECT UNLOCK WARNING SWITCH ASSEMBLY
Remove the unlock warning switch assembly .
Measure the resistance according to the value(s) in
the table below.
Standard resistance
...
