AIRBAG SYSTEM, Diagnostic DTC:B1825/56, B1826/56, B1827/56, B1828/56

DTC Code DTC Name
B1825/56 Short in Side Squib LH Circuit
B1826/56 Open in Side Squib LH Circuit
B1827/56 Short to GND in Side Squib LH Circuit
B1828/56 Short to B+ in Side Squib LH Circuit

DESCRIPTION

The front side squib LH circuit consists of the center airbag sensor assembly and front seat airbag LH.

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

These DTCs are stored when a malfunction is detected in the front side squib LH circuit.

DTC Code DTC Detection Condition Trouble Area
B1825/56

One of the following conditions is met:


  • The center airbag sensor assembly detects a line short circuit signal 5 times in the front side squib LH circuit during the primary check.

  • A front side squib LH malfunction.

  • A center airbag sensor assembly malfunction.

  • Front seat wire LH

  • No. 2 floor wire

  • Front seat airbag assembly LH (Front side squib LH)

  • Center airbag sensor assembly
B1826/56

One of the following conditions is met:


  • The center airbag sensor assembly detects an open circuit signal in the front side squib LH circuit for 2 seconds.

  • A front side squib LH malfunction.

  • A center airbag sensor assembly malfunction.
B1827/56

One of the following conditions is met:


  • The center airbag sensor assembly detects a short circuit to ground signal in the front side squib LH circuit for 0.5 seconds.

  • A front side squib LH malfunction.

  • A center airbag sensor assembly malfunction.
B1828/56

One of the following conditions is met:


  • The center airbag sensor assembly detects a short circuit to B+ signal in the front side squib LH circuit for 0.5 seconds.

  • A front side squib LH malfunction.

  • A center airbag sensor assembly malfunction.

WIRING DIAGRAM

A01FEZCE10

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

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 AIRBAG ASSEMBLY LH (FRONT SIDE SQUIB LH)


    1. A01FED3E01
      Text in Illustration
      *1 Front Side Squib LH
      *2 Center Airbag Sensor Assembly
      *3 Connector E
      *4 SST
      *a

      Front view of wire harness connector

      (to Front Side Squib LH)
      *b Color: Red

      Turn the engine 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 airbag LH.

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

      CAUTION:

      Never connect the tester to the front seat airbag LH (front side 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 cable to the negative (-) battery terminal, 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 B1825/56, B1826/56, B1827/56 or B1828/56 is not output.

      Tech Tips

      Codes other than DTC B1825/56, B1826/56, B1827/56 and B1828/56 may be output at this time, but they are not related to this check.

    11. Turn the engine switch off.

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

    13. Disconnect SST from connector E.


    NG

    CHECK CONNECTOR Click here

    OK

    REPLACE FRONT SEAT AIRBAG ASSEMBLY LH Click here

  2. CHECK CONNECTOR


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

    2. A01FJ1WE01
      Text in Illustration
      *1 Front Side Squib LH
      *2 Center Airbag Sensor Assembly

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

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

    NG

    REPLACE HARNESS AND CONNECTOR

    OK

  3. CHECK FRONT SIDE SQUIB LH CIRCUIT


    1. A01FEVDE01
      Text in Illustration
      *1 Front Side Squib LH
      *2 Front Seat Wire LH
      *3 No. 2 Floor Wire
      *4 Center Airbag Sensor Assembly
      *5 Connector E
      *a

      Front view of wire harness connector

      (to Front Side Squib LH)

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

    2. Turn the engine switch on (IG).

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      d32-1 (SFL+) - Body ground Engine switch on (IG) Below 1 V
      d32-2 (SFL-) - Body ground Engine switch on (IG) Below 1 V

    4. Turn the engine switch off.

    5. Disconnect the cable from the negative (-) 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
      d32-1 (SFL+) - d32-2 (SFL-) 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
      d32-1 (SFL+) - d32-2 (SFL-) Always 1 MΩ or higher
      d32-1 (SFL+) - Body ground Always 1 MΩ or higher
      d32-2 (SFL-) - Body ground Always 1 MΩ or higher

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


    NG

    CHECK FRONT SEAT WIRE LH Click here

    OK

  4. CHECK CENTER AIRBAG SENSOR ASSEMBLY


    1. A01FIWSE01
      Text in Illustration
      *1 Front Side Squib LH
      *2 Center Airbag Sensor Assembly

      Connect the connectors to the front seat airbag LH and center airbag sensor assembly.

    2. Connect the cable to the negative (-) battery terminal, 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 B1825/56, B1826/56, B1827/56 or B1828/56 is not output.

      Tech Tips

      Codes other than DTC B1825/56, B1826/56, B1827/56 and B1828/56 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

  5. CHECK FRONT SEAT WIRE LH


    1. A01FFDYE01
      Text in Illustration
      *1 Front Side Squib LH
      *2 Front Seat Wire LH
      *3 No. 2 Floor Wire
      *4 Center Airbag Sensor Assembly
      *5 Connector E
      *a

      Front view of wire harness connector

      (to Front Side Squib LH)

      Disconnect the front seat wire LH from the No. 2 floor wire.

    2. Connect the cable to the negative (-) battery terminal, 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
      d32-1 (SFL+) - Body ground Engine switch on (IG) Below 1 V
      d32-2 (SFL-) - Body ground Engine switch on (IG) Below 1 V

    5. Turn the engine switch off.

    6. Disconnect the cable from the negative (-) battery terminal, 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
      d32-1 (SFL+) - d32-2 (SFL-) Always Below 1 Ω

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

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      d32-1 (SFL+) - d32-2 (SFL-) Always 1 MΩ or higher
      d32-1 (SFL+) - Body ground Always 1 MΩ or higher
      d32-2 (SFL-) - Body ground Always 1 MΩ or higher

    10. Restore the released activation prevention mechanism of connector D to its original condition.


    NG

    REPLACE FRONT SEAT WIRE LH

    OK

    REPLACE NO. 2 FLOOR WIRE