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 sensor 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 Test Mode / Check Mode
B1653/35 Seat Position Airbag Sensor Circuit Malfunction

Any of the following conditions is met:


  • The airbag sensor assembly detects a line short in the seat position airbag sensor circuit.

  • The airbag sensor assembly detects a short to ground in the seat position airbag sensor circuit.

  • The airbag sensor assembly detects a short to B+ in the seat position airbag sensor circuit.

  • The airbag sensor assembly detects an open in the seat position airbag sensor circuit.

  • Seat position airbag sensor malfunction

  • Airbag sensor assembly malfunction

    for LHD:

  • Floor wire

  • Front No. 2 seat wire LH

  • Seat position airbag sensor

  • Airbag sensor assembly


    for RHD:

  • Floor wire

  • Front seat wire RH

  • Seat position airbag sensor

  • Airbag sensor assembly

 Does not apply to test/check mode
DTC Detection Conditions:
Vehicle Condition
Pattern 1 Pattern 2 Pattern 3 Pattern 4 Pattern 5 Pattern 6
Diagnosis Condition Ignition switch ON ○ ○ ○ ○ ○ ○
Malfunction Status The airbag sensor assembly detects a line short in the seat position airbag sensor circuit ○ - - - - -
The airbag sensor assembly detects a short to ground in the seat position airbag sensor circuit - ○ - - - -
The airbag sensor assembly detects a short to B+ in the seat position airbag sensor circuit - - ○ - - -
The airbag sensor assembly detects an open in the seat position airbag sensor circuit - - - ○ - -
Seat position airbag sensor malfunction - - - - ○ -
Airbag sensor assembly malfunction - - - - - ○
Detection Time - - - - - -
Number of Trips 1 trip 1 trip 1 trip 1 trip 1 trip 1 trip

Tech Tips

DTC will be output when conditions for either of the patterns in the table above are met.

WIRING DIAGRAM


  1. for LHD:

    A001XQIE02

  2. for RHD:

    A001UL0E08

CAUTION / NOTICE / HINT

Note

After turning the ignition 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

PROCEDURE


  1. CHECK VEHICLE CONDITION


    1. Choose the model to be inspected.

      Result
      Result Proceed to
      for LHD A
      for RHD B

    B

    CHECK SEAT POSITION AIRBAG SENSOR CIRCUIT (OPEN) Click here

    A

  2. CHECK CONNECTORS


    1. Turn the ignition switch off.

    2. Disconnect the cable from the negative (-) battery terminal.

      CAUTION:

      Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to disable the SRS system.

    3. Check that the connectors are properly connected to the airbag sensor assembly and seat position airbag sensor. Also check that the connectors that link the front No. 2 seat wire LH and floor wire are properly connected.

      OK
      The connectors are properly connected.

      Tech Tips

      If the connectors are not properly connected, reconnect the connectors and proceed to the next inspection.

    4. Disconnect the connectors from the airbag sensor assembly and seat position airbag sensor. Also disconnect the connectors that link the front No. 2 seat wire LH and floor wire.

    5. Check that the terminals of the connectors are not deformed or damaged.

      OK
      The terminals are not deformed or damaged.
      Result
      Proceed to
      OK
      NG

    NG

    REPLACE WIRE HARNESS

    OK

  3. CHECK SEAT POSITION AIRBAG SENSOR CIRCUIT (OPEN)


    1. Connect the connectors that link the front No. 2 seat wire LH and floor wire.

      A001UY5C01
      *A w/o Dual-stage SRS *B w/ Dual-stage SRS
      *1 Seat Position Airbag Sensor *2 Airbag Sensor Assembly
      *3 Service Wire - -
      *a

      Front view of wire harness connector

      (to Airbag Sensor Assembly)

      		 *b

      Front view of wire harness connector

      (to Seat Position Airbag Sensor)

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

      Note

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

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      M49-2 (LSP+) - M49-1 (LSP-) Always Below 1 Ω
      Result
      Proceed to
      OK
      NG

    NG

    REPLACE FLOOR WIRE

    OK

  4. CHECK SEAT POSITION AIRBAG SENSOR CIRCUIT (SHORT)


    1. Disconnect the service wire from connector B.

      A001SUMC01
      *A w/o Dual-stage SRS *B w/ Dual-stage SRS
      *1 Seat Position Airbag Sensor *2 Airbag Sensor Assembly
      *a

      Front view of wire harness connector

      (to Seat Position Airbag Sensor)

      		 - -

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      M49-2 (LSP+) - M49-1 (LSP-) Always 1 MΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    REPLACE FLOOR WIRE

    OK

  5. CHECK SEAT POSITION AIRBAG SENSOR CIRCUIT (SHORT TO B+)


    1. Connect the cable to the negative (-) battery terminal.

      A001SUMC01
      *A w/o Dual-stage SRS *B w/ Dual-stage SRS
      *1 Seat Position Airbag Sensor *2 Airbag Sensor Assembly
      *a

      Front view of wire harness connector

      (to Seat Position Airbag Sensor)

      		 - -

    2. Turn the ignition switch ON.

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      M49-1 (LSP-) - Body ground Ignition switch ON Below 1 V
      M49-2 (LSP+) - Body ground Ignition switch ON Below 1 V

    4. Turn the ignition switch off.

    5. Disconnect the cable from the negative (-) battery terminal.

      CAUTION:

      Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to disable the SRS system.

      Result
      Proceed to
      OK
      NG

    NG

    REPLACE FLOOR WIRE

    OK

  6. CHECK SEAT POSITION AIRBAG SENSOR CIRCUIT (SHORT TO GROUND)


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

      A001SUMC01
      *A w/o Dual-stage SRS *B w/ Dual-stage SRS
      *1 Seat Position Airbag Sensor *2 Airbag Sensor Assembly
      *a

      Front view of wire harness connector

      (to Seat Position Airbag Sensor)

      		 - -
      Standard Resistance
      Tester Connection Condition Specified Condition
      M49-1 (LSP-) - Body ground Always 1 MΩ or higher
      M49-2 (LSP+) - Body ground Always 1 MΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    REPLACE FLOOR WIRE

    OK

  7. CHECK DTC


    1. A001WT3C01
      *A w/o Dual-stage SRS
      *B w/ Dual-stage SRS
      *1 Seat Position Airbag Sensor
      *2 Airbag Sensor Assembly

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

    2. Connect the cable to the negative (-) battery terminal.

    3. Clear the DTCs stored in memory.

      Click here


      Body Electrical > SRS Airbag > Clear DTCs

    4. Turn the ignition switch off.

    5. Turn the ignition switch ON, and wait for at least 60 seconds.

    6. Check for DTCs.

      Click here


      Body Electrical > SRS Airbag > Trouble Codes
      OK
      DTC B1653/35 is not output.

      Tech Tips

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

      Result
      Proceed to
      OK
      NG

    OK

    USE SIMULATION METHOD TO CHECK Click here

    NG

  8. CHECK SEAT POSITION AIRBAG SENSOR


    1. A001WT3C01
      *A w/o Dual-stage SRS
      *B w/ Dual-stage SRS
      *1 Seat Position Airbag Sensor
      *2 Airbag Sensor Assembly

      Turn the ignition switch off.

    2. Disconnect the cable from the negative (-) battery terminal.

      CAUTION:

      Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to disable the SRS system.

    3. Replace the seat position airbag sensor with a known good one.

      Click here

      Tech Tips

      Perform the following inspection using known good parts from another vehicle if possible.

    4. Connect the cable to the negative (-) battery terminal.

    5. Clear the DTCs stored in memory.

      Click here


      Body Electrical > SRS Airbag > Clear DTCs

    6. Turn the ignition switch off.

    7. Turn the ignition switch ON, and wait for at least 60 seconds.

    8. Check for DTCs.

      Click here


      Body Electrical > SRS Airbag > Trouble Codes
      OK
      DTC B1653/35 is not output.

      Tech Tips

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

    9. Turn the ignition switch off.

    10. Disconnect the cable from the negative (-) battery terminal.

      CAUTION:

      Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to disable the SRS system.

    11. Restore the seat position airbag sensor that was installed for testing to its original location.

      Click here

      Result
      Proceed to
      OK
      NG

    OK

    REPLACE SEAT POSITION AIRBAG SENSOR Click here

    NG

    REPLACE AIRBAG SENSOR ASSEMBLY Click here

  9. CHECK SEAT POSITION AIRBAG SENSOR CIRCUIT (OPEN)


    1. A001UL4C10
      *1 Seat Position Airbag Sensor
      *2 Airbag Sensor Assembly
      *3 Service Wire
      *a

      Front view of wire harness connector

      (to Airbag Sensor Assembly)
      *b

      Front view of wire harness connector

      (to Seat Position Airbag Sensor)

      Connect the connectors that link the front seat wire RH and floor wire.

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

      Note

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

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      Y3-2 (VS) - Y3-1 (GND) Always Below 1 Ω
      Result
      Proceed to
      OK
      NG

    NG

    CHECK FLOOR WIRE (OPEN) Click here

    OK

  10. CHECK SEAT POSITION AIRBAG SENSOR CIRCUIT (SHORT)


    1. A001SZSC09
      *1 Seat Position Airbag Sensor
      *2 Airbag Sensor Assembly
      *a

      Front view of wire harness connector

      (to Seat Position Airbag Sensor)

      Disconnect the service wire from connector B.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      Y3-2 (VS) - Y3-1 (GND) Always 1 MΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    CHECK FLOOR WIRE (SHORT) Click here

    OK

  11. CHECK SEAT POSITION AIRBAG SENSOR CIRCUIT (SHORT TO B+)


    1. A001SZSC09
      *1 Seat Position Airbag Sensor
      *2 Airbag Sensor Assembly
      *a

      Front view of wire harness connector

      (to Seat Position Airbag Sensor)

      Connect the cable to the negative (-) battery terminal.

    2. Turn the ignition switch ON.

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      Y3-2 (VS) - Body ground Ignition switch ON Below 1 V
      Y3-1 (GND) - Body ground Ignition switch ON Below 1 V

    4. Turn the ignition switch off.

    5. Disconnect the cable from the negative (-) battery terminal.

      CAUTION:

      Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to disable the SRS system.

      Result
      Proceed to
      OK
      NG

    NG

    CHECK FLOOR WIRE (SHORT TO B+) Click here

    OK

  12. CHECK SEAT POSITION AIRBAG SENSOR CIRCUIT (SHORT TO GROUND)


    1. A001SZSC09
      *1 Seat Position Airbag Sensor
      *2 Airbag Sensor Assembly
      *a

      Front view of wire harness connector

      (to Seat Position Airbag Sensor)

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      Y3-2 (VS) - Body ground Always 1 MΩ or higher
      Y3-1 (GND) - Body ground Always 1 MΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    CHECK FLOOR WIRE (SHORT TO GROUND) Click here

    OK

  13. CHECK DTC


    1. A001TTUC01
      *1 Seat Position Airbag Sensor
      *2 Airbag Sensor Assembly

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

    2. Connect the cable to the negative (-) battery terminal.

    3. Clear the DTCs stored in memory.

      Click here


      Body Electrical > SRS Airbag > Clear DTCs

    4. Turn the ignition switch off.

    5. Turn the ignition switch ON, and wait for at least 60 seconds.

    6. Check for DTCs.

      Click here


      Body Electrical > SRS Airbag > Trouble Codes
      OK
      DTC B1653/35 is not output.

      Tech Tips

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

      Result
      Proceed to
      OK
      NG

    OK

    USE SIMULATION METHOD TO CHECK Click here

    NG

  14. CHECK SEAT POSITION AIRBAG SENSOR


    1. A001TTUC01
      *1 Seat Position Airbag Sensor
      *2 Airbag Sensor Assembly

      Turn the ignition switch off.

    2. Disconnect the cable from the negative (-) battery terminal.

      CAUTION:

      Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to disable the SRS system.

    3. Replace the seat position airbag sensor with a known good one.

      Click here

      Tech Tips

      Perform the following inspection using known good parts from another vehicle if possible.

    4. Connect the cable to the negative (-) battery terminal.

    5. Clear the DTCs stored in memory.

      Click here


      Body Electrical > SRS Airbag > Clear DTCs

    6. Turn the ignition switch off.

    7. Turn the ignition switch ON, and wait for at least 60 seconds.

    8. Check for DTCs.

      Click here


      Body Electrical > SRS Airbag > Trouble Codes
      OK
      DTC B1653/35 is not output.

      Tech Tips

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

    9. Turn the ignition switch off.

    10. Disconnect the cable from the negative (-) battery terminal.

      CAUTION:

      Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to disable the SRS system.

    11. Restore the seat position airbag sensor that was installed for testing to its original location.

      Click here

      Result
      Proceed to
      OK
      NG

    OK

    REPLACE SEAT POSITION AIRBAG SENSOR Click here

    NG

    REPLACE AIRBAG SENSOR ASSEMBLY Click here

  15. CHECK FLOOR WIRE (SHORT TO GROUND)


    1. A001UNLC03
      *1 Seat Position Airbag Sensor
      *2 Airbag Sensor Assembly
      *3 Front Seat Wire RH
      *4 Floor Wire
      *a

      Front view of wire harness connector

      (to Front Seat Wire RH)

      Disconnect the floor wire connector from the front seat wire RH.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      MY2-2 (RSP+) - Body ground Always 1 MΩ or higher
      MY2-1 (RSP-) - Body ground Always 1 MΩ or higher
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE FRONT SEAT WIRE RH

    NG

    REPLACE FLOOR WIRE

  16. CHECK FLOOR WIRE (SHORT TO B+)


    1. A001UNLC03
      *1 Seat Position Airbag Sensor
      *2 Airbag Sensor Assembly
      *3 Front Seat Wire RH
      *4 Floor Wire
      *a

      Front view of wire harness connector

      (to Front Seat Wire RH)

      Disconnect the floor wire connector from the front seat wire RH.

    2. Connect the cable to the negative (-) battery terminal.

    3. Turn the ignition switch ON.

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      MY2-2 (RSP+) - Body ground Ignition switch ON Below 1 V
      MY2-1 (RSP-) - Body ground Ignition switch ON Below 1 V
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE FRONT SEAT WIRE RH

    NG

    REPLACE FLOOR WIRE

  17. CHECK FLOOR WIRE (SHORT)


    1. A001UNLC03
      *1 Seat Position Airbag Sensor
      *2 Airbag Sensor Assembly
      *3 Front Seat Wire RH
      *4 Floor Wire
      *a

      Front view of wire harness connector

      (to Front Seat Wire RH)

      Disconnect the floor wire connector from the front seat wire RH.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      MY2-2 (RSP+) - MY2-1 (RSP-) Always 1 MΩ or higher
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE FRONT SEAT WIRE RH

    NG

    REPLACE FLOOR WIRE

  18. CHECK FLOOR WIRE (OPEN)


    1. A001TRAC03
      *1 Seat Position Airbag Sensor
      *2 Airbag Sensor Assembly
      *3 Front Seat Wire RH
      *4 Floor Wire
      *5 Service Wire
      *a

      Front view of wire harness connector

      (to Airbag Sensor Assembly)
      *b

      Front view of wire harness connector

      (to Front Seat Wire RH)

      Disconnect the floor wire connector from the front seat wire RH.

      Tech Tips

      The service wire has already been inserted into connector B.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      MY2-2 (RSP+) - MY2-1 (RSP-) Always Below 1 Ω

    3. Disconnect the service wire from the connector B.

      Result
      Proceed to
      OK
      NG

    OK

    REPLACE FRONT SEAT WIRE RH

    NG

    REPLACE FLOOR WIRE