Seat position airbag sensor circuit malfunction

Description
The seat position sensor circuit consists of the center airbag sensor and the seat position sensor.
Dtc b1653/35 is recorded when a malfunction is detected in the seat position sensor circuit.

Wiring diagram

Inspection procedure
- Check for dtc

- Turn the ignition switch on, and wait for at least 60 seconds.
- Clear the dtcs (see page rs-49).
- Turn the ignition switch off.
- Turn the ignition switch on, and wait for at least 60 seconds.
- Check the dtcs (see page rs-49).
Dtcs other than dtc b1653/35 may be output at this time, but they are not related to this check.

- Check connection of connector
- Turn the ignition switch off.
- Disconnect the cable from the negative (-) battery terminal, and wait for at least 90 seconds.
- Check that the connectors are properly connected to the center airbag sensor and the seat position sensor.

- Check seat position sensor circuit (open)

- Disconnect the connectors from the center airbag sensor and the seat position sensor.
- Using a service wire, connect 2 and 1 of connector e.
Do not forcibly insert the service wire into the terminals of the connector when connecting.
- Measure the resistance of the wire harness side connector.
W/ curtain shield airbag

- Check seat position sensor circuit (short)

- Disconnect the service wire from connector e.
- Measure the resistance of the wire harness side connector.

- Check seat position sensor circuit (to b+)

- Connect the cable to the negative (-) battery terminal, and wait for at least 2 seconds.
- Turn the ignition switch on.
- Measure the voltage of the wire harness side connector.

- Check seat position sensor circuit (to ground)

- Turn the ignition switch off.
- Disconnect the cable from the negative (-) battery terminal, and wait for at least 90 seconds.
- Measure the voltage of the wire harness side connector.

- Check seat position sensor

- Connect the connectors to the center airbag sensor and the seat position sensor.
- Connect the cable to the negative (-) battery terminal, and wait for at least 2 seconds.
- Turn the ignition switch on, and wait for at least 60 seconds.
- Clear the dtcs (see page rs-49).
- Turn the ignition switch off.
- Turn the ignition switch on, and wait for at least 60 seconds.
- Check the dtcs (see page rs-49).
Dtcs other than dtc b1653/35 may be output at this time, but they are not related to this check.


- Replace seat position sensor
- Turn the ignition switch off.
- Disconnect the cable from the negative (-) battery terminal, and wait for at least 90 seconds.
- Replace the seat position sensor (see page rs-389).
Perform the inspection using parts from a normal vehicle if possible.

- Check center airbag sensor assembly

- Connect the cable to the negative (-) battery terminal, and wait for at least 2 seconds.
- Turn the ignition switch on, and wait for at least 60 seconds.
- Clear the dtcs (see page rs-49).
- Turn the ignition switch off
- Turn the ignition switch on, and wait for at least 60 seconds.
- Check the dtcs (see page rs-49).
Dtcs other than dtc b1653/35 may be output at this time, but they are not related to this check.

End
- Check floor wire (open)

- Disconnect the front seat inner belt connector from the flow wire.
- Using a service wire, connect k4-1 (lsp+) and k4-2 (lsp-) of connector c.
Do not forcibly insert the service wire into the terminals of the connector when connecting.
- Measure the resistance of the wire harness side connectors.
W/ curtain shield airbag

Replace front seat inner belt assembly lh
- Check floor wire (short)

- Disconnect the front seat inner belt connector from the floor wire.
- Measure the resistance of the wire harness side connector.

Replace front seat inner belt assembly lh
- Check floor wire (to b+)

- Turn the ignition switch off.
- Disconnect the cable from the negative (-) battery terminal, and wait for at least 90 seconds.
- Disconnect the front seat inner belt connector from the floor wire.
- Connect the cable to the negative (-) battery terminal, and wait for at least 2 seconds.
- Turn the ignition switch on.
- Measure the voltage of the wire harness side connectors.

Replace front seat inner belt assembly lh
- Check floor wire (to ground)

- Disconnect the front seat inner belt connector from the floor wire.
- Measure the resistance of the wire harness side connectors.

Replace front seat inner belt assembly lh
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