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

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

DESCRIPTION

The front pretensioner squib RH circuit consists of the airbag sensor assembly and front seat outer belt assembly RH.

The airbag sensor assembly uses this circuit to deploy the seat belt pretensioner when deployment conditions are met.

These DTCs are stored when a malfunction is detected in the front pretensioner squib RH circuit.

DTC No. DTC Detection Condition Trouble Area
B1900/73
  • The airbag sensor assembly receives a line short circuit signal in the front pretensioner squib RH circuit during primary check.

  • Front pretensioner squib RH malfunction

  • Airbag sensor assembly malfunction


  • No. 2 floor wire

  • Front seat outer belt assembly RH (Front pretensioner squib RH)

  • Airbag sensor assembly

B1901/73
  • The airbag sensor assembly receives an open circuit signal in the front pretensioner squib RH circuit.

  • Front pretensioner squib RH malfunction

  • Airbag sensor assembly malfunction

B1902/73
  • The airbag sensor assembly receives a short circuit to ground signal in the front pretensioner squib RH circuit.

  • Front pretensioner squib RH malfunction

  • Airbag sensor assembly malfunction

B1903/73
  • The airbag sensor assembly receives a short circuit to B+ signal in the front pretensioner squib RH circuit.

  • Front pretensioner squib RH malfunction

  • Airbag sensor assembly malfunction

WIRING DIAGRAM

A01W4EGE59
*a Front Seat Outer Belt Assembly RH (Front Pretensioner Squib RH)
*b Airbag Sensor Assembly

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.

Tech Tips


  • Perform the simulation method by selecting check mode (Signal Check) using the GTS Click here.

  • After selecting check mode (Signal Check), perform the simulation method by wiggling each connector of the airbag system or driving the vehicle on a city road or rough road Click here.

PROCEDURE


  1. CHECK CONNECTORS


    1. A01W0QYE07
      Text in Illustration
      *1 Front Seat Outer Belt Assembly RH
      *2 Airbag Sensor Assembly
      *3 No. 2 Floor Wire

      Turn the engine 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 front seat outer belt assembly RH and airbag sensor assembly.

      OK
      The connectors are properly connected.

      Tech Tips

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

    4. Disconnect the connectors from the front seat outer belt assembly RH and airbag sensor assembly.

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

      OK
      The terminals are not deformed or damaged.
    6. Check that the No. 2 floor wire connector (on the front seat outer belt assembly RH side) is not damaged.

      OK
      The lock button is not disengaged, and the claw of the lock is not deformed or damaged.
    7. Check that the short spring for the No. 2 floor wire with the activation prevention mechanism is not deformed or damaged.

      OK
      The short spring is not deformed or damaged.

    NG
    OK
  2. CHECK FRONT SEAT OUTER BELT ASSEMBLY RH (FRONT PRETENSIONER SQUIB RH)


    1. A01VZ5VE02
      Text in Illustration
      *1 Front Seat Outer Belt Assembly RH
      *2 Airbag Sensor Assembly
      *a

      Front view of wire harness connector

      (to Front Seat Outer Belt Assembly RH)

      Connect the connector to the airbag sensor assembly.

    2. Connect SST (resistance 2.1 Ω) to connector C.

      CAUTION:

      Never connect the tester to the front seat outer belt assembly RH (front pretensioner squib RH) for measurement, as this may lead to a serious injury due to pretensioner deployment.

      Note


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

      • Insert SST straight into the terminals of the connector.

      SST
      09843-18061
    3. Connect the cable to the negative (-) battery terminal.

    4. Clear the DTCs stored in memory Click here.

    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.

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

      Tech Tips

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

    8. Turn the engine switch off.

    9. 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.

    10. Disconnect SST from connector C.


    OK
    NG
  3. CHECK NO. 2 FLOOR WIRE


    1. A01W0DQE02
      Text in Illustration
      *1 Front Seat Outer Belt Assembly RH
      *2 Airbag Sensor Assembly
      *3 No. 2 Floor Wire
      *a

      Front view of wire harness connector

      (to Front Seat Outer Belt Assembly RH)

      Disconnect the No. 2 floor wire from the airbag sensor assembly.

    2. Check for a short to B+ in the circuit.


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

      2. Turn the engine switch on (IG).

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

        Standard Voltage
        Tester Connection Condition Specified Condition
        Q9-1 (R+) - Body ground Engine switch on (IG) Below 1 V
        Q9-2 (R-) - Body ground Engine switch on (IG) Below 1 V
      4. Turn the engine 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.

    3. Check for an open in the circuit.


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

        Standard Resistance
        Tester Connection Condition Specified Condition
        Q9-1 (R+) - Q9-2 (R-) Always Below 1 Ω
    4. Check for a short to ground in the circuit.


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

        Standard Resistance
        Tester Connection Condition Specified Condition
        Q9-1 (R+) - Body ground Always 1 MΩ or higher
        Q9-2 (R-) - Body ground Always 1 MΩ or higher
    5. Check for a short in the circuit.


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

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

        Standard Resistance
        Tester Connection Condition Specified Condition
        Q9-1 (R+) - Q9-2 (R-) Always 1 MΩ or higher
      3. Restore the released activation prevention mechanism of connector B to the original condition.


    NG
    OK
  4. CHECK DTC


    1. A01VZPJE01
      Text in Illustration
      *1 Front Seat Outer Belt Assembly RH
      *2 Airbag Sensor Assembly

      Connect the connectors to the front seat outer belt assembly RH and airbag sensor assembly.

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

    3. Clear the DTCs stored in memory Click here.

    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.

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

      Tech Tips

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


    OK
    NG