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

This circuit instructs the SRS to deploy when deployment conditions are met.

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

DTC Code DTC Detection Condition Trouble Area
B1900/73

One of the following conditions is met:


  • The center airbag sensor assembly detects a line short circuit signal 5 times in the front seat belt pretensioner RH circuit during the primary check.

  • A front seat belt pretensioner RH malfunction.

  • A center airbag sensor assembly malfunction.

  • Floor wire

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

  • Center airbag sensor assembly
B1901/73

One of the following conditions is met:


  • The center airbag sensor assembly detects an open circuit signal in the front seat belt pretensioner RH circuit for 2 seconds.

  • A front seat belt pretensioner RH malfunction.

  • A center airbag sensor assembly malfunction.
B1902/73

One of the following conditions is met:


  • The center airbag sensor assembly detects a short circuit to ground signal in the front seat belt pretensioner RH circuit for 0.5 seconds.

  • A front seat belt pretensioner RH malfunction.

  • A center airbag sensor assembly malfunction.
B1903/73

One of the following conditions is met:


  • The center airbag sensor assembly detects a short circuit to B+ signal in the front seat belt pretensioner RH circuit for 0.5 seconds.

  • A front seat belt pretensioner RH malfunction.

  • A center airbag sensor assembly malfunction.

WIRING DIAGRAM

A01FTIKE18

INSPECTION PROCEDURE

Note


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

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

Tech Tips

To perform the simulation method, enter check mode (signal check) with the GTS Click here, and then wiggle each connector of the airbag system or drive the vehicle on various types of road Click here.

PROCEDURE


  1. CHECK FRONT SEAT OUTER BELT ASSEMBLY RH (FRONT SEAT BELT PRETENSIONER RH)


    1. A01FSW2E05
      Text in Illustration
      *1 Front Seat Belt Pretensioner RH
      *2 Center Airbag Sensor Assembly
      *3 Connector C
      *4 SST
      *a

      Front view of wire harness connector

      (to Front Seat Belt Pretensioner RH)

      Turn the power switch off.

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

    3. Disconnect the connectors from the front seat outer belt assembly RH.

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

      CAUTION:

      Never connect the tester to the front seat outer belt assembly RH (front seat belt pretensioner RH) 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 SST.

      • Insert SST straight into the terminals of the connector.

      SST
      09843-18061

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

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

    7. Clear the DTCs Click here.

    8. Turn the power switch off.

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

    10. Check for DTCs Click here.

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

      Tech Tips

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

    11. Turn the power switch off.

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

    13. Disconnect SST from connector C.


    NG

    CHECK CONNECTOR Click here

    OK

    REPLACE FRONT SEAT OUTER BELT ASSEMBLY RH Click here

  2. CHECK CONNECTOR


    1. Disconnect the connectors from the center airbag sensor assembly.

    2. A01FR1UE02
      Text in Illustration
      *1 Front Seat Belt Pretensioner RH
      *2 Floor Wire
      *3 Center Airbag Sensor Assembly

      Check that the connectors (on the center airbag sensor assembly side and front seat outer belt assembly RH side) are not damaged.

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

    NG

    REPLACE FLOOR WIRE

    OK

  3. CHECK FRONT SEAT BELT PRETENSIONER RH CIRCUIT


    1. A01FQWZE05
      Text in Illustration
      *1 Front Seat Belt Pensioner RH
      *2 Floor Wire
      *3 Center Airbag Sensor Assembly
      *4 Connector C
      *a

      Front view of wire harness connector

      (to Front Seat Belt Pretensioner RH)

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

    2. Turn the power switch on (IG).

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      T8-1 (R+) - Body ground Power switch on (IG) Below 1 V
      T8-2 (R-) - Body ground Power switch on (IG) Below 1 V

    4. Turn the power switch off.

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

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      T8-1 (R+) - T8-2 (R-) Always Below 1 Ω

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

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      T8-1 (R+) - T8-2 (R-) Always 1 MΩ or higher
      T8-1 (R+) - Body ground Always 1 MΩ or higher
      T8-2 (R-) - Body ground Always 1 MΩ or higher

    9. Restore the released activation prevention mechanism of connector B to its original condition.


    NG

    REPLACE FLOOR WIRE

    OK

  4. CHECK CENTER AIRBAG SENSOR ASSEMBLY


    1. A01FQG3E25
      Text in Illustration
      *1 Front Seat Belt Pretensioner RH
      *2 Center Airbag Sensor Assembly

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

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

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

    4. Clear the DTCs stored in memory Click here.

    5. Turn the power switch off.

    6. Turn the power 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 DTC B1900/73, B1901/73, B1902/73 and B1903/73 may be output at this time, but they are not related to this check.


    NG

    REPLACE CENTER AIRBAG SENSOR ASSEMBLY Click here

    OK

    USE SIMULATION METHOD TO CHECK Click here