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

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

DESCRIPTION

The side squib (D seat side) circuit consists of the center airbag sensor assembly and the front seat airbag assembly.

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

These DTCs are set when a malfunction is detected in the side squib (D seat side) circuit.

DTC No. DTC Detecting Conditions Trouble Areas
B1820

  • Center airbag sensor assembly receives line short circuit signal in side squib (D seat side) circuit 5 times during check

  • Side squib (D seat side) malfunction

  • Center airbag sensor assembly malfunction

  • Floor wire

  • Front seat airbag assembly (D seat side)

  • Center airbag sensor assembly
B1821

  • Center airbag sensor assembly receives open circuit signal in side squib (D seat side) circuit for 2 seconds

  • Side squib (D seat side) malfunction

  • Center airbag sensor assembly malfunction

  • Floor wire

  • Front seat airbag assembly (D seat side)

  • Center airbag sensor assembly
B1822

  • Center airbag sensor assembly receives short circuit to ground signal in side squib (D seat side) circuit for 0.5 seconds

  • Side squib (D seat side) malfunction

  • Center airbag sensor assembly malfunction

  • Floor wire

  • Front seat airbag assembly (D seat side)

  • Center airbag sensor assembly
B1823

  • Center airbag sensor assembly receives short circuit to B+ signal in side squib (D seat side) circuit for 0.5 seconds

  • Side squib (D seat side) malfunction

  • Center airbag sensor assembly malfunction

  • Floor wire

  • Front seat airbag assembly (D seat side)

  • Center airbag sensor assembly

WIRING DIAGRAM

A01388HE01

INSPECTION PROCEDURE

Tech Tips

Perform a check mode inspection after repairing the squib system to check if the repair has done correctly Click here.

PROCEDURE


  1. CHECK FRONT SEAT AIRBAG ASSEMBLY (D SQUIB)

    SST
    09843-18060

    1. A0136DCE01

      Turn the ignition switch to the LOCK position.

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

    3. Disconnect the connectors from the front seat airbag assembly (D seat side).

    4. Connect the black wire side of SST (resistance 2.1 Ω) to the floor wire.

      CAUTION:

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

      Note


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

      • Insert the SST straight into the terminal of the connector.

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

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

    7. Clear the DTCs stored in memory.

    8. Turn the ignition switch to the LOCK position.

    9. Turn the ignition switch to the ON position, and wait for at least 60 seconds.

    10. Check the DTCs.

      OK
      DTC B1820, B1821, B1822 and B1823 are not output.

    OK

    REPLACE FRONT SEAT AIRBAG ASSEMBLY LH (LHD)

    OK

    REPLACE FRONT SEAT AIRBAG ASSEMBLY RH (RHD)

    NG

  2. CHECK CONNECTOR


    1. Turn the ignition switch to the LOCK position.

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

    3. Check that the connector (on the front seat airbag assembly side) is not damaged Click here.

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

    NG

    REPAIR OR REPLACE WIRE HARNESS

    OK

  3. CHECK CONNECTION OF CONNECTOR


    1. Check that the connectors are properly connected to the center airbag sensor assembly and the airbag sensor front RH.

      OK
      The connectors are properly connected.

    NG

    CONNECT CONNECTOR

    OK

  4. CHECK FLOOR WIRE (D SQUIB CIRCUIT)


    1. A0137SXE01

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

    2. Turn the ignition switch to the ON position.

    3. Measure the voltage.

      Standard Voltage
      Tester Connection Condition Specified Condition
      H13-4 (SFL+) - Body ground (*1) Ignition switch ON Below 1 V
      H13-3 (SFL-) - Body ground (*1) Ignition switch ON Below 1 V
      H14-4 (SFR+) - Body ground (*2) Ignition switch ON Below 1 V
      H14-3 (SFR-) - Body ground (*2) Ignition switch ON Below 1 V

      *1:LHD

      *2:RHD

    4. Turn the ignition switch to the LOCK position.

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

    6. Measure the resistance.

      Standard Resistance
      Tester Connection Condition Specified Condition
      H13-4 (SFL+) - H13-3 (SFL-) (*1) Always Below 1 Ω
      H13-4 (SFL+) - Body ground (*1) Always 1 MΩ or Higher
      H13-3 (SFL-) - Body ground (*1) Always 1 MΩ or Higher
      H14-4 (SFR+) - H14-3 (SFR-) (*2) Always Below 1 Ω
      H14-4 (SFR+) - Body ground (*2) Always 1 MΩ or Higher
      H14-3 (SFR-) - Body ground (*2) Always 1 MΩ or Higher

      *1:LHD

      *2:RHD

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

    8. Measure the resistance.

      Standard Resistane
      Tester Connection Condition Specified Condition
      H13-4 (SFL+) - H13-3 (SFL-) (*1) Always 1 MΩ or Higher
      H14-4 (SFR+) - H14-3 (SFR-) (*2) Always 1 MΩ or Higher

      *1:LHD

      *2:RHD


    NG

    REPAIR OR REPLACE FLOOR WIRE

    OK

    REPLACE CENTER AIRBAG SENSOR ASSEMBLY