AIRBAG SYSTEM, Diagnostic DTC:B1820/55, B1821/55, B1822/55, B1823/55

DTC Code DTC Name
B1820/55 Short in Front Driver Side - Side Squib Circuit
B1821/55 Open in Front Driver Side - Side Squib Circuit
B1822/55 Short to GND in Front Driver Side - Side Squib Circuit
B1823/55 Short to B+ in Front Driver Side - Side Squib Circuit

DESCRIPTION

The driver side - side squib circuit consists of the center airbag sensor and the driver side - side airbag.

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

These DTCs are recorded when a malfunction is detected in the driver side - side squib circuit.

DTC Code Detection Condition Trouble Area
B1820/55

When all conditions below are met:


  • The center airbag sensor receives a line short circuit signal 5 times in the driver side - side squib circuit during primary check.

  • Driver side - side squib malfunction

  • Center airbag sensor malfunction

  • Floor wire

  • Front seat side airbag assembly (driver side)

  • Center airbag sensor assembly
B1821/55

When all conditions below are met:


  • The center airbag sensor receives an open circuit signal in the driver side - side squib circuit for 2 seconds.

  • Driver side - side squib malfunction

  • Center airbag sensor malfunction

  • Floor wire

  • Front seat side airbag assembly (driver side)

  • Center airbag sensor assembly
B1822/55

When all conditions below are met:


  • The center airbag sensor receives a short circuit to ground signal in the driver side - side squib circuit for 0.5 seconds.

  • Driver side - side squib malfunction

  • Center airbag sensor malfunction

  • Floor wire

  • Front seat side airbag assembly (driver side)

  • Center airbag sensor assembly
B1823/55

When all conditions below are met:


  • The center airbag sensor receives a short circuit to B+ signal in the driver side - side squib circuit for 0.5 seconds.

  • Driver side - side squib malfunction

  • Center airbag sensor malfunction

  • Floor wire

  • Front seat side airbag assembly (driver side)

  • Center airbag sensor assembly

WIRING DIAGRAM

A01DY61E15
A01DY61E16

INSPECTION PROCEDURE

PROCEDURE


  1. CHECK VEHICLE CONDITION


    1. Check vehicle condition.

      Result
      Result Proceed to
      for LHD A
      for RHD B

    B

    CHECK FRONT SEAT SIDE AIRBAG ASSEMBLY RH Click here

    A

  2. CHECK FRONT SEAT SIDE AIRBAG LH (SIDE SQUIB LH)

    A01DX9DE01

    1. Turn the ignition switch OFF.

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

    3. Disconnect the connector from the front seat side airbag LH.

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

      CAUTION:

      Never connect the tester to the front seat side airbag LH (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 negative (-) terminal cable to the battery, 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 B1820, B1821, B1822 or B1823 is not output

      Tech Tips

      Codes other than DTC B1820, B1821, B1822, B1823 may be output at this time, but they are not related to this check.


    NG

    CHECK FLOOR WIRE (SIDE SQUIB LH CIRCUIT) Click here

    OK

    REPLACE FRONT SEATBACK ASSEMBLY LH

  3. CHECK FLOOR WIRE (SIDE SQUIB LH CIRCUIT)

    A01DX8WE01

    1. Turn the ignition 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. Disconnect the connectors from the center airbag sensor.

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

    6. Turn the ignition switch ON.

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

      Standard voltage
      Tester Connection Switch Condition Specified Condition
      S39-1 (SFL+) - Body ground Ignition switch ON Below 1 V
      S39-2 (SFL-) - Body ground

    8. Turn the ignition switch OFF.

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

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

      Standard resistance
      Tester Connection Condition Specified Condition
      S39-1 (SFL+) - S39-2 (SFL-) Always Below 1 Ω

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

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

      Standard resistance
      Tester Connection Condition Specified Condition
      S39-1 (SFL+) - S39-2 (SFL-) Always 1 MΩ or higher
      S39-1 (SFL+) - Body ground
      S39-2 (SFL-) - Body ground

    NG

    REPLACE FLOOR WIRE

    OK

  4. CHECK CENTER AIRBAG SENSOR ASSEMBLY

    A01E05OE01

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

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

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

    4. Clear the DTCs Click here.

    5. Turn the ignition switch OFF.

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

    7. Check for DTCs Click here.

      OK
      DTC B1820, B1821, B1822 or B1823 is not output

      Tech Tips

      Codes other than DTC B1820, B1821, B1822, B1823 may be output at this time, but they are not related to this check.


    NG

    REPLACE CENTER AIRBAG SENSOR ASSEMBLY

    OK

    USE SIMULATION METHOD TO CHECK

  5. CHECK FRONT SEAT SIDE AIRBAG ASSEMBLY RH

    A01DX9DE02

    1. Turn the ignition switch OFF.

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

    3. Disconnect the connector from the front seat side airbag RH.

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

      CAUTION:

      Never connect the tester to the front seat side airbag RH (side squib 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.

    5. Connect the negative (-) terminal cable to the battery, 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 B1820, B1821, B1822 or B1823 is not output

      Tech Tips

      Codes other than DTC B1820, B1821, B1822 or B1823 may be output at this time, but they are not related to this check.


    NG

    CHECK FLOOR WIRE (SIDE SQUIB RH CIRCUIT) Click here

    OK

    REPLACE FRONT SEATBACK ASSEMBLY RH

  6. CHECK FLOOR WIRE (SIDE SQUIB RH CIRCUIT)

    A01DX8WE02

    1. Turn the ignition 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. Disconnect the connectors from the center airbag sensor.

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

    6. Turn the ignition switch ON.

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

      Standard voltage
      Tester Connection Switch Condition Specified Condition
      S38-1 (SFR+) - Body ground Ignition switch ON Below 1 V
      S38-2 (SFR-) - Body ground

    8. Turn the ignition switch OFF.

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

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

      Standard resistance
      Tester Connection Condition Specified Condition
      S38-1 (SFR+) - S38-2 (SFR-) Always Below 1 Ω

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

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

      Standard resistance
      Tester Connection Condition Specified Condition
      S38-1 (SFR+) - S38-2 (SFR-) Always 1 MΩ or higher
      S38-1 (SFR+) - Body ground
      S38-2 (SFR-) - Body ground

    NG

    REPLACE FLOOR WIRE (SIDE SQUIB LH CIRCUIT)

    OK

  7. CHECK CENTER AIRBAG SENSOR ASSEMBLY

    A01E05OE05

    1. Connect the connectors to the front seat side airbag RH and the center airbag sensor.

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

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

    4. Clear the DTCs Click here.

    5. Turn the ignition switch OFF.

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

    7. Check for DTCs Click here.

      OK
      DTC B1820, B1821, B1822 or B1823 is not output

      Tech Tips

      Codes other than B1820, B1821, B1822 or B1823 may be output at this time, but they are not related to this check.


    NG

    REPLACE CENTER AIRBAG SENSOR ASSEMBLY

    OK

    USE SIMULATION METHOD TO CHECK