AIRBAG SYSTEM, Diagnostic DTC:B1653/35

DTC Code DTC Name
B1653/35 Seat Position Airbag Sensor Circuit Malfunction

DESCRIPTION

The seat position airbag sensor circuit consists of the airbag ECU assembly and seat position airbag sensor.

DTC B1653/35 is stored when a malfunction is detected in the seat position airbag sensor circuit.

DTC No. Detection Item DTC Detection Condition Trouble Area
B1653/35 Seat Position Airbag Sensor Circuit Malfunction

    One of the following conditions is met:

  • The airbag ECU assembly detects a line short circuit signal, open circuit signal, short circuit to ground signal or short circuit to B+ signal in the seat position airbag sensor circuit for 2 seconds.

  • A seat position airbag sensor malfunction.

  • An airbag ECU assembly malfunction

  • Floor wire (for RHD)

  • Front seat inner belt assembly RH (for RHD)

  • No. 2 floor wire (for LHD)

  • Front seat inner belt assembly LH (for LHD)

  • Seat position airbag sensor

  • Airbag ECU assembly

WIRING DIAGRAM

B008JMEE08

CAUTION / NOTICE / HINT

Note


  • After turning the engine switch off, waiting time may be required before disconnecting the cable from the negative (-) battery terminal. Therefore, make sure to read the disconnecting the cable from the negative (-) battery terminal notices before proceeding with work.

    Click here

  • When disconnecting the cable from the negative (-) battery terminal while performing repairs, some systems need to be initialized after the cable is reconnected.

    Click here

  • After replacing the airbag ECU assembly, refer to initialization.

    Click here

PROCEDURE


  1. CHECK VEHICLE CONDITION


    1. Check vehicle condition.

      Result
      Proceed to
      for LHD
      for RHD

    for RHD

    CHECK CONNECTION OF CONNECTORS Click here

    for LHD

  2. CHECK CONNECTION OF CONNECTORS


    1. Turn the engine 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 airbag ECU assembly and seat position airbag sensor.

      Result
      Proceed to
      Connectors are properly connected
      Connectors are not properly connected

    Connectors are not properly connected

    CONNECT CONNECTORS PROPERLY

    Connectors are properly connected

  3. CHECK CONNECTORS


    1. B008J0PC02
      *1 Seat Position Airbag Sensor
      *2 Airbag ECU Assembly
      *3 Front Seat Inner Belt Assembly LH
      *4 No. 2 Floor Wire

      Disconnect the connectors from the airbag ECU assembly and seat position airbag sensor.

    2. Check that the connectors (on the airbag ECU assembly side and seat position airbag sensor side) are not damaged.

      Result
      Proceed to
      Connectors are not deformed or damaged
      Connectors are deformed or damaged

    Connectors are deformed or damaged

    REPLACE NO. 2 FLOOR WIRE OR FRONT SEAT INNER BELT ASSEMBLY LH

    Connectors are not deformed or damaged

  4. CHECK SEAT POSITION AIRBAG SENSOR CIRCUIT


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

      B008HVDC03
      *1 Seat Position Airbag Sensor *2 Airbag ECU Assembly
      *3 Connector E *4 Connector B
      *5 Service Wire - -
      *a

      Front view of wire harness connector

      (to Seat Position Airbag Sensor)

      		 *b

      Rear view of wire harness connector

      (to Airbag ECU Assembly)

    2. Turn the engine switch on (IG).

    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      1 (LSP-) - Body ground Engine switch on (IG) Below 1 V
      2 (LSP+) - Body ground Engine switch on (IG) Below 1 V

    4. Turn the engine switch off.

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

    6. Using a service wire, connect terminals 24 (LSP-) and 16 (LSP+) of connector B.

      Note

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

    7. Measure the resistance according to the value(s) in the table below.

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

    8. Disconnect the service wire from connector B.

    9. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      1 (LSP-) - 2 (LSP+) Always 1 MΩ or higher
      1 (LSP-) - Body ground Always 1 MΩ or higher
      2 (LSP+) - Body ground Always 1 MΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    CHECK NO. 2 FLOOR WIRE Click here

    OK

  5. CHECK DTC


    1. B008J7BC01
      *1 Seat Position Airbag Sensor
      *2 Airbag ECU Assembly

      Connect the connectors to the airbag ECU assembly and seat position airbag sensor.

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

    3. Turn the engine switch on (IG), and wait for at least 60 seconds.

    4. Clear the DTCs.

      Click here


      Body Electrical > SRS Airbag > Clear DTCs

    5. Turn the engine switch off.

    6. Turn the engine switch on (IG), and wait for at least 60 seconds.

    7. Check for DTCs.

      Click here


      Body Electrical > SRS Airbag > Trouble Codes
      Result
      Proceed to
      DTC B1653/35 is not output
      DTC B1653/35 is output

      Tech Tips

      Codes other than DTC B1653/35 may be output at this time, but they are not related to this check.


    DTC B1653/35 is not output

    USE SIMULATION METHOD TO CHECK Click here

    DTC B1653/35 is output

  6. REPLACE SEAT POSITION AIRBAG SENSOR


    1. Turn the engine switch off.

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

    3. Replace the seat position airbag sensor.

      for Manual Seat: Click here

      for Power Seat: Click here

      Tech Tips

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

      Result
      Proceed to
      NEXT

    NEXT

  7. CHECK DTC


    1. B008J7BC01
      *1 Seat Position Airbag Sensor
      *2 Airbag ECU Assembly

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

    2. Turn the engine switch on (IG), and wait for at least 60 seconds.

    3. Clear the DTCs.

      Click here


      Body Electrical > SRS Airbag > Clear DTCs

    4. Turn the engine switch off.

    5. Turn the engine switch on (IG), and wait for at least 60 seconds.

    6. Check for DTCs.

      Click here


      Body Electrical > SRS Airbag > Trouble Codes
      Result
      Proceed to
      DTC B1653/35 is not output
      DTC B1653/35 is output

      Tech Tips

      Codes other than DTC B1653/35 may be output at this time, but they are not related to this check.


    DTC B1653/35 is not output

    END (SEAT POSITION AIRBAG SENSOR WAS DEFECTIVE)

    DTC B1653/35 is output

    REPLACE AIRBAG ECU ASSEMBLY Click here

  8. CHECK NO. 2 FLOOR WIRE


    1. Disconnect the No. 2 floor wire connector from the front seat inner belt assembly LH.

      B008IXFC03
      *1 Seat Position Airbag Sensor *2 Airbag ECU Assembly
      *3 Front Seat Inner Belt Assembly LH *4 No. 2 Floor Wire
      *5 Connector C *6 Connector B
      *7 Service Wire - -
      *a

      Front view of wire harness connector

      (to Front Seat Inner Belt Assembly LH)

      		 *b

      Rear view of wire harness connector

      (to Airbag ECU Assembly)

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

    3. Turn the engine switch on (IG).

    4. Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      Q45-4 (LSP+) - Body ground Engine switch on (IG) Below 1 V
      Q45-3 (LSP-) - Body ground Engine switch on (IG) Below 1 V

    5. Turn the engine switch off.

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

    7. Using a service wire, connect terminals 24 (LSP-) and 16 (LSP+) of connector B.

      Note

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

    8. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      Q45-4 (LSP+) - Q45-3 (LSP-) Always Below 1 Ω

    9. Disconnect the service wire from connector B.

    10. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      Q45-4 (LSP+) - Q45-3 (LSP-) Always 1 MΩ or higher
      Q45-4 (LSP+) - Body ground Always 1 MΩ or higher
      Q45-3 (LSP-) - Body ground Always 1 MΩ or higher
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE FRONT SEAT INNER BELT ASSEMBLY LH for Manual Seat: Click here
    REPLACE FRONT SEAT INNER BELT ASSEMBLY LH for Power Seat: Click here

    NG

    REPLACE NO. 2 FLOOR WIRE

  9. CHECK CONNECTION OF CONNECTORS


    1. Turn the engine 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 airbag ECU assembly and seat position airbag sensor.

      Result
      Proceed to
      Connectors are properly connected
      Connectors are not properly connected

    Connectors are not properly connected

    CONNECT CONNECTORS PROPERLY

    Connectors are properly connected

  10. CHECK CONNECTORS


    1. B008HVWC27
      *1 Seat Position Airbag Sensor
      *2 Airbag ECU Assembly
      *3 Floor Wire
      *4 Front Seat Inner Belt Assembly RH

      Disconnect the connectors from the airbag ECU assembly and seat position airbag sensor.

    2. Check that the connectors (on the airbag ECU assembly side and seat position airbag sensor side) are not damaged.

      Result
      Proceed to
      Connectors are not deformed or damaged
      Connectors are deformed or damaged

    Connectors are deformed or damaged

    REPLACE FLOOR WIRE OR FRONT SEAT INNER BELT ASSEMBLY RH

    Connectors are not deformed or damaged

  11. CHECK SEAT POSITION AIRBAG SENSOR CIRCUIT


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

      B008HPRC01
      *1 Seat Position Airbag Sensor *2 Airbag ECU Assembly
      *3 Connector E *4 Connector B
      *5 Service Wire - -
      *a

      Front view of wire harness connector

      (to Seat Position Airbag Sensor)

      		 *b

      Rear view of wire harness connector

      (to Airbag ECU Assembly)

    2. Turn the engine switch on (IG).

    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      1 (RSP-) - Body ground Engine switch on (IG) Below 1 V
      2 (RSP+) - Body ground Engine switch on (IG) Below 1 V

    4. Turn the engine switch off.

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

    6. Using a service wire, connect terminals 17 (RSP-) and 9 (RSP+) of connector B.

      Note

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

    7. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      1 (RSP-) - 2 (RSP+) Always Below 1 Ω

    8. Disconnect the service wire from connector B.

    9. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      1 (RSP-) - 2 (RSP+) Always 1 MΩ or higher
      1 (RSP-) - Body ground Always 1 MΩ or higher
      2 (RSP+) - Body ground Always 1 MΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    CHECK FLOOR WIRE Click here

    OK

  12. CHECK DTC


    1. B008I6MC01
      *1 Seat Position Airbag Sensor
      *2 Airbag ECU Assembly

      Connect the connectors to the airbag ECU assembly and seat position airbag sensor.

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

    3. Turn the engine switch on (IG), and wait for at least 60 seconds.

    4. Clear the DTCs.

      Click here


      Body Electrical > SRS Airbag > Clear DTCs

    5. Turn the engine switch off.

    6. Turn the engine switch on (IG), and wait for at least 60 seconds.

    7. Check for DTCs.

      Click here


      Body Electrical > SRS Airbag > Trouble Codes
      Result
      Proceed to
      DTC B1653/35 is not output
      DTC B1653/35 is output

      Tech Tips

      Codes other than DTC B1653/35 may be output at this time, but they are not related to this check.


    DTC B1653/35 is not output

    USE SIMULATION METHOD TO CHECK Click here

    DTC B1653/35 is output

  13. REPLACE SEAT POSITION AIRBAG SENSOR


    1. Turn the engine switch off.

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

    3. Replace the seat position airbag sensor.

      for Manual Seat: Click here

      for Power Seat: Click here

      Tech Tips

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

      Result
      Proceed to
      NEXT

    NEXT

  14. CHECK DTC


    1. B008I6MC01
      *1 Seat Position Airbag Sensor
      *2 Airbag ECU Assembly

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

    2. Turn the engine switch on (IG), and wait for at least 60 seconds.

    3. Clear the DTCs.

      Click here


      Body Electrical > SRS Airbag > Clear DTCs

    4. Turn the engine switch off.

    5. Turn the engine switch on (IG), and wait for at least 60 seconds.

    6. Check for DTCs.

      Click here


      Body Electrical > SRS Airbag > Trouble Codes
      Result
      Proceed to
      DTC B1653/35 is not output
      DTC B1653/35 is output

      Tech Tips

      Codes other than DTC B1653/35 may be output at this time, but they are not related to this check.


    DTC B1653/35 is not output

    END (SEAT POSITION AIRBAG SENSOR WAS DEFECTIVE)

    DTC B1653/35 is output

    REPLACE AIRBAG ECU ASSEMBLY Click here

  15. CHECK FLOOR WIRE


    1. Disconnect the wire connector from the front seat inner belt assembly LH.

      B008IEIC01
      *1 Seat Position Airbag Sensor *2 Airbag ECU Assembly
      *3 Front Seat Inner Belt Assembly RH *4 Floor Wire
      *5 Connector C *6 Connector B
      *7 Service Wire - -
      *a

      Front view of wire harness connector

      (to Front Seat Inner Belt Assembly RH)

      		 *b

      Rear view of wire harness connector

      (to Airbag ECU Assembly)

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

    3. Turn the engine switch on (IG).

    4. Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      P12-4 (RSP+) - Body ground Engine switch on (IG) Below 1 V
      P12-3 (RSP-) - Body ground Engine switch on (IG) Below 1 V

    5. Turn the engine switch off.

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

    7. Using a service wire, connect terminals 17 (RSP-) and 9 (RSP+) of connector B.

      Note

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

    8. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      P12-4 (RSP+) - P12-3 (RSP-) Always Below 1 Ω

    9. Disconnect the service wire from connector B.

    10. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      P12-4 (RSP+) - P12-3 (RSP-) Always 1 MΩ or higher
      P12-4 (RSP+) - Body ground Always 1 MΩ or higher
      P12-3 (RSP-) - Body ground Always 1 MΩ or higher
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE FRONT SEAT INNER BELT ASSEMBLY RH for Manual Seat: Click here
    REPLACE FRONT SEAT INNER BELT ASSEMBLY RH for Power Seat: Click here

    NG

    REPLACE FLOOR WIRE