Dtc B1653/35 Seat Position Airbag Sensor Circuit Malfunction

Vehicle Interior. Yaris. Ncp93, 131
Supplemental Restraint Systems. Yaris. Ncp93, 131

DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

CHECK DTC

CHECK CONNECTION OF CONNECTORS

CHECK SEAT POSITION SENSOR CIRCUIT (FOR OPEN)

CHECK SEAT POSITION SENSOR CIRCUIT (FOR SHORT)

CHECK SEAT POSITION SENSOR CIRCUIT (TO B+)

CHECK SEAT POSITION SENSOR CIRCUIT (TO GROUND)

CHECK SEAT POSITION SENSOR

REPLACE SEAT POSITION SENSOR

CHECK CENTER AIRBAG SENSOR ASSEMBLY

CHECK FLOOR WIRE (FOR OPEN)

CHECK FLOOR WIRE (FOR SHORT)

CHECK FLOOR WIRE (TO B+)

CHECK FLOOR WIRE (TO GROUND)

DTC B1653/35 Seat Position Airbag Sensor Circuit Malfunction


DESCRIPTION

The seat position sensor circuit consists of the center airbag sensor assembly and the seat position sensor.
DTC B1653/35 is recorded when a malfunction is detected in the seat position sensor circuit.

DTC No.
DTC Detecting Condition
Trouble Area
B1653/35
  1. Center airbag sensor assembly detects line short circuit signal, open circuit signal, short circuit to ground signal or short circuit to B+ signal in seat position sensor circuit for 2 seconds.
  2. Seat position sensor malfunction
  3. Center airbag sensor assembly malfunction
  1. Floor wire
  2. Front seat inner belt assembly LH
  3. Seat position sensor
  4. Center airbag sensor assembly

WIRING DIAGRAM


Yaris. Ncp93, 131.Supplemental Restraint Systems.Airbag System (For Sedan). Dtc B1653/35 Seat Position Airbag Sensor Circuit Malfunction


INSPECTION PROCEDURE

NOTICE:
In order to prevent unexpected airbag deployment, disconnect the following connectors before inspecting parts such as wire harnesses, if the application of tester probes to the center airbag sensor assembly connector is necessary.
  1. Turn the ignition switch to the lock position.
  2. Disconnect the negative (-) terminal cable from the battery, and wait for at least 90 seconds.
  3. Disconnect the connector from the center airbag sensor assembly.
  4. Disconnect the connectors from the steering pad.
  5. Disconnect the connectors from the front passenger airbag assembly.
  6. Disconnect the connector from the front seat outer belt assembly LH
  7. Disconnect the connector from the front seat outer belt assembly RH.
    HINT:
    Skip the following steps if side and curtain shield airbags are not fitted.
  8. Disconnect the connector from the front seat side airbag assembly LH.
  9. Disconnect the connector from the front seat side airbag assembly RH.
  10. Disconnect the connector from the curtain shield airbag assembly LH.
  11. Disconnect the connector from the curtain shield airbag assembly RH.
1.CHECK DTC


    Yaris. Ncp93, 131.Supplemental Restraint Systems.Airbag System (For Sedan). Dtc B1653/35 Seat Position Airbag Sensor Circuit Malfunction

  1. Turn the ignition switch on, and wait for at least 60 seconds.

  1. Clear the DTCs stored in the memory (YARIS_NCP93 RM000000XFE0D2X.html).

  1. Turn the ignition switch off.

  1. Turn the ignition switch on, and wait for at least 60 seconds.

  1. Check the DTCs (YARIS_NCP93 RM000000XFE0D2X.html).

    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.


OK
USE SIMULATION METHOD TO CHECK
NG


2.CHECK CONNECTION OF CONNECTORS

  1. Turn the ignition switch off.

  1. Disconnect the negative (-) terminal cable from the battery, and wait for at least 90 seconds.

  1. Check that the connectors are properly connected to the center airbag sensor assembly and the seat position sensor.

    OK:
    The connectors are properly connected.


NG
CONNECT CONNECTORS
OK


3.CHECK SEAT POSITION SENSOR CIRCUIT (FOR OPEN)
Yaris. Ncp93, 131.Supplemental Restraint Systems.Airbag System (For Sedan). Dtc B1653/35 Seat Position Airbag Sensor Circuit Malfunction

  1. Disconnect the connectors from the center airbag sensor assembly and the seat position sensor.

  1. Using a service wire, connect J8-14 (DSP+) and J8-13 (DSP-) of connector B.

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

  1. Measure the resistance.

    Standard resistance:
    Tester Connection
    		Condition
    		Specified Condition
    2 (LSP+) - 1 (LSP-)
    		Always
    		Below 1 Ω


NG
Go to step 10
OK


4.CHECK SEAT POSITION SENSOR CIRCUIT (FOR SHORT)
Yaris. Ncp93, 131.Supplemental Restraint Systems.Airbag System (For Sedan). Dtc B1653/35 Seat Position Airbag Sensor Circuit Malfunction

  1. Disconnect the service wire from connector B.

  1. Measure the resistance.

    Standard resistance:
    Tester Connection
    		Condition
    		Specified Condition
    2 (LSP+) - 1 (LSP-)
    		Always
    		1 MΩ or higher


NG
Go to step 11
OK


5.CHECK SEAT POSITION SENSOR CIRCUIT (TO B+)
Yaris. Ncp93, 131.Supplemental Restraint Systems.Airbag System (For Sedan). Dtc B1653/35 Seat Position Airbag Sensor Circuit Malfunction

  1. Connect the negative (-) terminal cable to the battery, and wait for at least 2 seconds.

  1. Turn the ignition switch on.

  1. Measure the voltage.

    Standard voltage:
    Tester Connection
    		Switch Condition
    		Specified Condition
    2 (LSP+) - Body ground
    		Ignition switch ON
    		Below 1 V
    1 (LSP-) - Body ground
    		Ignition switch ON
    		Below 1 V


NG
Go to step 12
OK


6.CHECK SEAT POSITION SENSOR CIRCUIT (TO GROUND)
Yaris. Ncp93, 131.Supplemental Restraint Systems.Airbag System (For Sedan). Dtc B1653/35 Seat Position Airbag Sensor Circuit Malfunction

  1. Turn the ignition switch off.

  1. Disconnect the negative (-) terminal cable from the battery, and wait for at least 90 seconds.

  1. Measure the voltage.

    Standard resistance:
    Tester Connection
    		Condition
    		Specified Condition
    2 (LSP+) - Body ground
    		Always
    		1 MΩ or Higher
    1 (LSP-) - Body ground
    		Always
    		1 MΩ or Higher


NG
Go to step 13
OK


7.CHECK SEAT POSITION SENSOR
Yaris. Ncp93, 131.Supplemental Restraint Systems.Airbag System (For Sedan). Dtc B1653/35 Seat Position Airbag Sensor Circuit Malfunction

  1. Connect the connectors to the center airbag sensor assembly and the seat position sensor.

  1. Connect the negative (-) terminal cable to the battery, and wait for at least 2 seconds.

  1. Turn the ignition switch on, and wait for at least 60 seconds.

  1. Clear the DTCs stored in the memory (YARIS_NCP93 RM000000XFE0D2X.html).

  1. Turn the ignition switch off.

  1. Turn the ignition switch on, and wait for at least 60 seconds.

  1. Check the DTCs (YARIS_NCP93 RM000000XFE0D2X.html).

    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.


OK
USE SIMULATION METHOD TO CHECK
NG


8.REPLACE SEAT POSITION SENSOR

  1. Turn the ignition switch off.

  1. Disconnect the negative (-) terminal cable from the battery, and wait for at least 90 seconds.

  1. Replace the seat position sensor (YARIS_NCP93 RM0000012DQ00TX.html).

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

NEXT


9.CHECK CENTER AIRBAG SENSOR ASSEMBLY


    Yaris. Ncp93, 131.Supplemental Restraint Systems.Airbag System (For Sedan). Dtc B1653/35 Seat Position Airbag Sensor Circuit Malfunction

  1. Connect the negative (-) terminal cable to the battery, and wait for at least 2 seconds.

  1. Turn the ignition switch on, and wait for at least 60 seconds.

  1. Clear the DTCs stored in the memory (YARIS_NCP93 RM000000XFE0D2X.html).

  1. Turn the ignition switch off.

  1. Turn the ignition switch on, and wait for at least 60 seconds.

  1. Check the DTCs (YARIS_NCP93 RM000000XFE0D2X.html).

    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.


NG
REPLACE CENTER AIRBAG SENSOR ASSEMBLY
OK

END

10.CHECK FLOOR WIRE (FOR OPEN)
Yaris. Ncp93, 131.Supplemental Restraint Systems.Airbag System (For Sedan). Dtc B1653/35 Seat Position Airbag Sensor Circuit Malfunction

  1. Disconnect the connectors from the center airbag sensor assembly and the seat position sensor.

  1. Using a service wire, connect J8-14 (DSP+) and J8-13 (DSP-) of connector B.

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

  1. Measure the resistance.

    Standard resistance:
    Tester Connection
    		Condition
    		Specified Condition
    J10-2 (LSP+) -
    J10-1 (LSP-)
    		Always
    		Below 1 Ω


NG
REPAIR OR REPLACE FLOOR WIRE
OK

REPLACE FRONT SEAT INNER BELT ASSEMBLY LH

11.CHECK FLOOR WIRE (FOR SHORT)


    Yaris. Ncp93, 131.Supplemental Restraint Systems.Airbag System (For Sedan). Dtc B1653/35 Seat Position Airbag Sensor Circuit Malfunction

  1. Disconnect the service wire from connector B.

  1. Measure the resistance.

    Standard resistance:
    Tester Connection
    		Condition
    		Specified Condition
    J10-2 (LSP+) -
    J10-1 (LSP-)
    		Always
    		1 MΩ or higher


NG
REPAIR OR REPLACE FLOOR WIRE
OK

REPLACE FRONT SEAT INNER BELT ASSEMBLY LH

12.CHECK FLOOR WIRE (TO B+)


    Yaris. Ncp93, 131.Supplemental Restraint Systems.Airbag System (For Sedan). Dtc B1653/35 Seat Position Airbag Sensor Circuit Malfunction

  1. Connect the negative (-) terminal cable to the battery, and wait for at least 2 seconds.

  1. Turn the ignition switch on.

  1. Measure the voltage.

    Standard voltage:
    Tester Connection
    		Switch Condition
    		Specified Condition
    J10-2 (LSP+) -
    Body ground
    		Ignition switch ON
    		Below 1 V
    J10-1 (LSP-) -
    Body ground
    		Ignition switch ON
    		Below 1 V


NG
REPAIR OR REPLACE FLOOR WIRE
OK

REPLACE FRONT SEAT INNER BELT ASSEMBLY LH

13.CHECK FLOOR WIRE (TO GROUND)


    Yaris. Ncp93, 131.Supplemental Restraint Systems.Airbag System (For Sedan). Dtc B1653/35 Seat Position Airbag Sensor Circuit Malfunction

  1. Turn the ignition switch off.

  1. Disconnect the negative (-) terminal cable from the battery, and wait for at least 90 seconds.

  1. Measure the resistance.

    Standard resistance:
    Tester Connection
    		Condition
    		Specified Condition
    J10-2 (LSP+) -
    Body ground
    		Always
    		1 MΩ or higher
    J10-1 (LSP-) -
    Body ground
    		Always
    		1 MΩ or higher


NG
REPAIR OR REPLACE FLOOR WIRE
OK

REPLACE FRONT SEAT INNER BELT ASSEMBLY LH