AIRBAG SYSTEM, Diagnostic DTC:B1900/73, B1901/73, B1902/73, B1903/73

DTC Code DTC Name
B1900/73 Short in Front Driver Side Pretensioner Squib Circuit
B1901/73 Open in Front Driver Side Pretensioner Squib Circuit
B1902/73 Short to GND in Front Driver Side Pretensioner Squib Circuit
B1903/73 Short to B+ in Front Driver Side Pretensioner Squib Circuit

DESCRIPTION

The driver side front pretensioner squib circuit consists of the center airbag sensor and the front seat outer belt driver side. The circuit instructs the SRS to deploy when deployment conditions are met. These DTCs are recorded when a malfunction is detected in the driver side front pretensioner squib circuit.

DTC No. DTC Detection Condition Trouble Area
B1900/73

When one of following conditions is met:


  • Center airbag sensor assembly receives line short circuit signal 5 times in driver side front pretensioner squib circuit during primary check

  • Front pretensioner squib driver side malfunction

  • Center airbag sensor assembly malfunction

  • Front seat outer belt assembly driver side (driver side front pretensioner squib)

  • Center airbag sensor assembly

  • Floor wire
B1901/73

When one of following conditions is met:


  • Center airbag sensor assembly receives open circuit signal in driver side front pretensioner squib circuit for 2 seconds

  • Front pretensioner squib driver side malfunction

  • Center airbag sensor assembly malfunction

  • Front seat outer belt assembly driver side (driver side front pretensioner squib)

  • Center airbag sensor assembly

  • Floor wire
B1902/73

When one of following conditions is met:


  • Center airbag sensor assembly receives short circuit to ground signal in driver side front pretensioner squib circuit for 0.5 seconds

  • Front pretensioner squib driver side malfunction

  • Center airbag sensor assembly malfunction

  • Front seat outer belt assembly driver side (driver side front pretensioner squib)

  • Center airbag sensor assembly

  • Floor wire
B1903/73

When one of following conditions is met:


  • Center airbag sensor assembly receives short circuit to B+ signal in driver side front pretensioner squib circuit for 0.5 seconds

  • Front pretensioner squib driver side malfunction

  • Center airbag sensor assembly malfunction

  • Front seat outer belt assembly driver side (driver side front pretensioner squib)

  • Center airbag sensor assembly

  • Floor wire

WIRING DIAGRAM

A01J7JQE32

INSPECTION PROCEDURE

PROCEDURE


  1. CHECK FRONT SEAT OUTER BELT ASSEMBLY DRIVER SIDE (DRIVER SIDE FRONT PRETENSIONER SQUIB)

    A01J3R3E01

    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 connector from the front seat outer belt driver side.

    4. Connect the white wire side of SST (resistance 2.1 Ω) to the floor wire connector C.

      SST
      09843-18060

      CAUTION:

      Never connect a tester to the driver side front pretensioner squib for measurement, as this may lead to a serious injury due to airbag deployment.

      Note


      • Do not forcibly insert SST into the terminals of the connector when connecting.

      • Insert SST straight into the terminals of the connector.

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

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

    7. Clear the DTCs Click here.

    8. Turn the ignition switch OFF.

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

    10. Check for DTCs Click here.

      OK
      DTC B1900, B1901, B1902, B1903 or 73 is not output.

      Tech Tips

      DTCs other than DTC B1900, B1901, B1902, B1903 or 73 may be output at this time, but they are not related to this check.


    OK

    REPLACE FRONT SEAT OUTER BELT ASSEMBLY DRIVER SIDE (DRIVER SIDE FRONT PRETENSIONER SQUIB)

    NG

  2. CHECK CONNECTOR


    1. Turn the ignition switch OFF.

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

    3. Disconnect SST (resistance 2.1 Ω) from the floor wire.

    4. Check that the floor wire connector (on the front seat outer belt driver side) is not damaged.

      OK
      The lock button is not disengaged, or the claw of the lock is not deformed or damaged.

    NG

    REPAIR OR REPLACE FLOOR WIRE

    OK

  3. CHECK FLOOR WIRE

    A01J72AE01

    1. Disconnect the connector from the center airbag sensor.

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

    3. Turn the ignition switch ON.

    4. Measure the voltage of the wire harness side connector.

      Standard Voltage
      Type A
      Tester Connection Specified Condition
      F19-1 (R+) - Body ground Below 1 V
      F19-2 (R-) - Body ground Below 1 V
      Type B
      Tester Connection Specified Condition
      F37-1 (R+) - Body ground Below 1 V
      F37-2 (R-) - Body ground Below 1 V

    5. Turn the ignition switch OFF.

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

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

      Standard Resistance
      Type A
      Tester Connection Specified Condition
      F19-1 (R+) - F19-2 (R-) Below 1 Ω
      F19-1 (R+) - Body ground 1 MΩ or higher
      F19-2 (R-) - Body ground 1 MΩ or higher
      Type B
      Tester Connection Specified Condition
      F37-1 (R+) - F37-2 (R-) Below 1 Ω
      F37-1 (R+) - Body ground 1 MΩ or higher
      F37-2 (R-) - Body ground 1 MΩ or higher

    8. Release the activation prevention mechanism built into connector B Click here.

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

      Standard Resistance
      Type A
      Tester Connection Specified Condition
      F19-1 (R+) - F19-2 (R-) 1 MΩ or higher
      Type B
      Tester Connection Specified Condition
      F37-1 (R+) - F37-2 (R-) 1 MΩ or higher

    NG

    REPAIR OR REPLACE FLOOR WIRE

    OK

    REPLACE CENTER AIRBAG SENSOR ASSEMBLY