Toyota RAV4 Service Manual: Occupant classification ecu malfunction
Description
Dtc b1795 is recorded when a malfunction is detected in the occupant classification ecu.
Troubleshoot dtc b1771 first when dtc b1771 and b1795 are output simultaneously.
Wiring diagram
Inspection procedure
- Check for dtc
- Turn the ignition switch on, and wait for at least 10 seconds.
- Check the dtcs (see page rs-249).
Result 
Hint:
Dtcs other than dtc b1771 and b1795 may be output at this time, but they are not related to this check.
- Check fuse (ecu-b)
- Check the ecu-b fuse from the instrument panel junction block.
- Measure the resistance of the fuse.
Standard resistance:
below 1 
- Check wire harness (source voltage)
- Turn the ignition switch off.
- Disconnect the cable from the negative (-) battery terminal, and wait for at least 90 seconds.
- Disconnect the no. 2 Floor wire connector from the occupant classification ecu.
- Connect the negative (-) terminal cable to the battery, and wait for at least 2 seconds.
- Measure the voltage of the wire harness side connector.
Standard voltage 
- Turn the ignition switch off.
- Measure the resistance of the wire harness side connector
standard resistance 
- Replace occupant classification ecu
- Turn the ignition switch off.
- Disconnect the cable from the negative (-) battery terminal, and wait for at least 90 seconds.
- Replace the occupant classification ecu (see page rs- 392).
Hint:
Perform the inspection using parts from a normal vehicle if possible.
- Perform zero point calibration
- Connect the cable to the negative (-) battery terminal, and wait for at least 2 seconds.
- Connect the intelligent tester to the dlc3.
- Turn the ignition switch on.
- Using the intelligent tester, perform the zero point calibration (see page rs-241).
Ok: completed is displayed.
- Perform sensitivity check
- Using the intelligent tester, perform the sensitivity check (see page rs-241).
Standard value: 27 to 33 kg (59.52 To 72.75 Lb)
End
Open in occupant classification ecu battery positive line
Description
Dtc b1794 is set when a malfunction is detected in the occupant
classification ecu battery positive line.
Wiring diagram
Inspection procedure
Check for dtc
Turn ...
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 off.
In this mode, if the occupant classification ecu detects ...
Other materials:
Circuit opening relay
On-vehicle inspection
Disconnect cable from negative battery
terminal
Caution:
Wait at least 90 seconds after disconnecting the
cable from the negative (-) battery terminal to
prevent airbag and seat belt pretensioner activation.
Inspect instrument panel junction block
Notice:
Th ...
Rear occupant classification sensor rh collision detection
Description
Dtc b1788 is output when the occupant classification ecu receives a collision
detection signal sent by
the rear occupant classification sensor rh when an accident occurs.
Dtc b1788 is also output when the front seat rh is subjected to a strong impact,
even if an actual
acci ...
Data list / active test
Read data list
Hint:
Using the intelligent tester's data list allows switch,
sensor, actuator and other item values to be read without
removing any parts. Reading the data list early in
troubleshooting is one way to save time.
Connect the intelligent tester to the dlc3.
Turn the igni ...