Driver side seat belt buckle switch circuit malfunction

Description
The driver side seat belt buckle switch circuit consists of the center airbag sensor and the front seat inner belt lh.
Dtc b1655/37 is recorded when a malfunction is detected in the driver side seat belt buckle switch 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 b1655/37 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 front seat inner belt lh.

- Check floor wire (open)

- Disconnect the connectors from the center airbag sensor and the front seat inner belt lh.
- Using a service wire, connect k2-11 (lbe+) and k2-12 (lbe-) (w/o curtain shield airbag), or k1-10 (dbe+) and k1-18 (dbe-) (w/curtain shield airbag) of connector b.
Do not forcibly insert the service wire into the terminals of the connector when connecting.
- Measure the resistance of the wire harness side connector.

- Check floor wire (short)

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

- Check floor wire (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 floor wire (to ground)

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

- Check front seat inner belt assembly lh

- Connect the connector to the center airbag sensor and the front seat inner belt lh.
- Connect the negative (-) terminal cable to the battery, 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 b1655/37 may be output at this time, but they are not related to this check.

- Replace front seat inner belt assembly lh
- Turn the ignition switch off.
- Disconnect the cable from the negative (-) battery terminal, and wait for at least 90 seconds.
- Replace the front seat inner belt lh (see page sb-21).
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 b1655/37 may be output at this time, but they are not related to this check.


End
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