Occupant classification system malfunction

The occupant classification system circuit consists of the center airbag sensor and the occupant classification system.

When the center airbag sensor receives signals from the occupant classification ecu, it determines whether or not the front passenger airbag, front seat side airbag rh and seat belt pretensioner rh should be operated.

Dtc b1650/32 is set when a malfunction is detected in the occupant classification system circuit.

1. Check for dtc (center airbag sensor)

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

Dtcs other than b1650/32 may be output at this time, but they are not related to this check.

1. 1
   Check for dtc (occupant classification ecu)
2. 2
   Turn the ignition switch on, and wait for at least 10 seconds.
3. 3
   Using the intelligent tester (with can vim), check for dtcs of the occupant classification ecu (see page rs- 249).

1. 1
   Check connection of connector
2. 2
   Turn the ignition switch off.
3. 3
   Disconnect the cable from the negative (-) battery terminal, and wait for at least 90 seconds.
4. 4
   Check that the connectors are properly connected to the center airbag sensor and the occupant classification ecu.

4. Check floor wire (open)

1. 1
   Disconnect the connectors from the center airbag sensor and occupant classification ecu.
2. 2
   Using a service wire, connect l1-8 (fsr+) and l1-4 (fsr-) of connector c.

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.

W/ curtain shield airbag

W/o curtain shield airbag

5. Check floor wire (short)

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

W/ curtain shield airbag

W/o curtain shield airbag

6. Check floor wire (to b+)

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

W/ curtain shield airbag

W/o curtain shield airbag

7. Check floor wire (to ground)

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

W/ curtain shield airbag

W/o curtain shield airbag

8. Check center airbag sensor assembly

1. Replace the center airbag sensor (see page rs-374).

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

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

Dtcs other than b1650/32 may be output at this time, but they are not related to this check.

1. 1
   Replace occupant classification ecu
2. 2
   Turn the ignition switch off.
3. 3
   Disconnect the cable from the negative (-) battery terminal, and wait for at least 90 seconds
4. 4
   Replace the occupant classification ecu (see page rs- 392).

   

1. 1
   Perform zero point calibration
2. 2
   Connect the cable to the negative (-) battery terminal, and wait for at least 2 seconds.
3. 3
   Turn the ignition switch on.
4. 4
   Using the intelligent tester, perform the zero point calibration (see page rs-241).

1. 1
   Perform sensitivity check
2. 2
   Using the intelligent tester, perform the sensitivity check (see page rs-241).