AIRBAG SYSTEM, Diagnostic DTC:B1925/78, B1926/78, B1927/78, B1928/78

DTC Code DTC Name
B1925/78 Short in Rear Pretensioner Squib LH Circuit
B1926/78 Open in Rear Pretensioner Squib LH Circuit
B1927/78 Short to GND in Rear Pretensioner Squib LH Circuit
B1928/78 Short to B+ in Rear Pretensioner Squib LH Circuit

DESCRIPTION

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

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

These DTCs are recorded when a malfunction is detected in the rear pretensioner squib LH circuit.

DTC Code Detection Condition Trouble Area
B1925/78

One of the following conditions is met:


  • The center airbag sensor assembly receives a line short circuit signal 5 times in the rear pretensioner squib LH circuit during primary check.

  • Rear pretensioner squib LH malfunction

  • Center airbag sensor assembly malfunction

  • No. 2 floor wire

  • Rear seat outer belt assembly LH (Rear pretensioner squib LH)

  • Center airbag sensor assembly
B1926/78

One of the following conditions is met:


  • The center airbag sensor assembly receives an open circuit signal in the rear pretensioner squib LH circuit for 2 seconds.

  • Rear pretensioner squib LH malfunction

  • Center airbag sensor assembly malfunction

  • No. 2 floor wire

  • Rear seat outer belt assembly LH (Rear pretensioner squib LH)

  • Center airbag sensor assembly
B1927/78

One of the following conditions is met:


  • The center airbag sensor assembly receives a short circuit to ground signal in the rear pretensioner squib LH circuit for 0.5 seconds.

  • Rear pretensioner squib LH malfunction

  • Center airbag sensor assembly malfunction

  • No. 2 floor wire

  • Rear seat outer belt assembly LH (Rear pretensioner squib LH)

  • Center airbag sensor assembly
B1928/78

One of the following conditions is met:


  • The center airbag sensor assembly receives a short circuit to B+ signal in the rear pretensioner squib LH circuit for 0.5 seconds.

  • Rear pretensioner squib LH malfunction

  • Center airbag sensor assembly malfunction

  • No. 2 floor wire

  • Rear seat outer belt assembly LH (rear pretensioner squib LH)

  • Center airbag sensor assembly

WIRING DIAGRAM

A01GICPE73

INSPECTION PROCEDURE

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.

Tech Tips


  • Perform the simulation method by selecting the "check mode" (signal check) with the intelligent tester Click here.

  • After selecting the "check mode" (signal check), perform the simulation method by wiggling each connector of the airbag system or driving the vehicle on various types of roads Click here.

PROCEDURE


  1. CHECK REAR SEAT OUTER BELT LH (REAR PRETENSIONER SQUIB LH)

    A01GLHTE19

    1. Turn the engine switch off.

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

    3. Disconnect the connectors from the rear seat outer belt RH.

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

      CAUTION:

      Never connect a tester to the rear seat outer belt LH (rear pretensioner squib LH) 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 negative (-) terminal cable to the battery, and wait for at least 2 seconds.

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

    7. Clear the DTCs Click here.

    8. Turn the engine switch off.

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

    10. Check for DTCs Click here.

      OK
      DTC B1925, B1926, B1927, B1928 or 78 is not output.

      Tech Tips

      Codes other than DTC B1925, B1926, B1927, B1928 and 78 may be output at this time, but they are not related to this check.


    NG

    REPLACE REAR SEAT OUTER BELT ASSEMBLY LH Click here

    OK

  2. CHECK CONNECTOR


    1. Turn the engine switch off.

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

    3. Disconnect SST from connector C.

    4. Check that the No. 2 floor wire connector (on the rear seat outer belt LH side) is not damaged.


    NG

    REPLACE NO. 2 FLOOR WIRE

    OK

  3. CHECK NO. 2 FLOOR WIRE (REAR PRETENSIONER SQUIB LH CIRCUIT)

    A01GLQUE19

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

    2. Connect the negative (-) terminal cable to the battery, 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
      S84-1 (RL+) - Body ground Engine switch on (IG) Below 1 V
      S84-2 (RL-) - Body ground Engine switch on (IG) Below 1 V

    5. Turn the engine switch off.

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

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

      Standard resistance
      Tester Connection Condition Specified Condition
      S84-1 (RL+) - S84-2 (RL-) Always Below 1 Ω

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

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

      Standard resistance
      Tester Connection Condition Specified Condition
      S84-1 (RL+) - S84-2 (RL-) Always 1 MΩ or higher
      S84-1 (RL+) - Body ground Always 1 MΩ or higher
      S84-2 (RL-) - Body ground Always 1 MΩ or higher

    NG

    REPLACE NO. 2 FLOOR WIRE

    OK

  4. CHECK CENTER AIRBAG SENSOR ASSEMBLY

    A01GHTGE04

    1. Connect the connectors to the rear seat outer belt LH and the center airbag sensor assembly.

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

    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 B1925, B1926, B1927, B1928 or 78 is not output.

      Tech Tips

      Codes other than DTC B1925, B1926, B1927, B1928 and 78 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