Toyota RAV4 Service Manual: 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

1. Check for dtc

1. Turn the ignition switch on, and wait for at least 60 seconds.
2. Clear the dtcs (see page rs-49).
3. Turn the ignition switch off.
4. Turn the ignition switch on, and wait for at least 60 seconds.
5. Check the dtcs (see page rs-49).

Ok: dtc b1653/35 is not output.

Hint:

Dtcs other than dtc b1653/35 may be output at this time, but they are not related to this check.

2. Check connection of connector

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

Ok: the connectors are properly connected.

3. Check seat position sensor circuit (open)

1. Disconnect the connectors from the center airbag sensor and the seat position sensor.
2. Using a service wire, connect 2 and 1 of connector e.

Notice:

Do not forcibly insert the service wire into the terminals of the connector when connecting.

3. Measure the resistance of the wire harness side connector.

Standard resistance:

W/o curtain shield airbag

W/ curtain shield airbag

4. Check seat position sensor circuit (short)

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

Standard resistance

5. Check seat position sensor circuit (to b+)

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

Standard voltage

6. Check seat position sensor circuit (to ground)

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

Standard resistance

7. Check seat position sensor

1. Connect the connectors to the center airbag sensor and the seat position sensor.
2. Connect the cable to the negative (-) battery terminal, and wait for at least 2 seconds.
3. Turn the ignition switch on, and wait for at least 60 seconds.
4. Clear the dtcs (see page rs-49).
5. Turn the ignition switch off.
6. Turn the ignition switch on, and wait for at least 60 seconds.
7. Check the dtcs (see page rs-49).

Ok: dtc b1653/35 is not output.

Hint:

Dtcs other than dtc b1653/35 may be output at this time, but they are not related to this check.

8. Replace seat position sensor

1. Turn the ignition switch off.
2. Disconnect the cable from the negative (-) battery terminal, and wait for at least 90 seconds.
3. Replace the seat position sensor (see page rs-389).

Hint:

Perform the inspection using parts from a normal vehicle if possible.

9. Check center airbag sensor assembly

1. Connect the cable to the negative (-) battery terminal, and wait for at least 2 seconds.
2. Turn the ignition switch on, and wait for at least 60 seconds.
3. Clear the dtcs (see page rs-49).
4. Turn the ignition switch off
5. Turn the ignition switch on, and wait for at least 60 seconds.
6. Check the dtcs (see page rs-49).

Ok: dtc b1653/35 is not output.

Hint:

Dtcs other than dtc b1653/35 may be output at this time, but they are not related to this check.

End

10. Check floor wire (open)

1. Disconnect the front seat inner belt connector from the flow wire.
2. Using a service wire, connect k4-1 (lsp+) and k4-2 (lsp-) of connector c.

Notice:

Do not forcibly insert the service wire into the terminals of the connector when connecting.

3. Measure the resistance of the wire harness side connectors.

Standard resistance:

W/o curtain shield airbag

W/ curtain shield airbag

Replace front seat inner belt assembly lh

11. Check floor wire (short)

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

Standard resistance

Replace front seat inner belt assembly lh

12. Check floor wire (to b+)

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

Standard voltage

Replace front seat inner belt assembly lh

13. Check floor wire (to ground)

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

Standard resistance

Replace front seat inner belt assembly lh