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

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

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

DTC No. DTC Detection Condition Trouble Area
B1820/55

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

  • Front driver side - side squib malfunction

  • Center airbag sensor assembly malfunction

    for LHD:

  • No. 2 floor wire

  • Front seat wire LH

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

  • Center airbag sensor assembly


    for RHD:

  • Floor wire

  • Front seat wire RH

  • Front seat side airbag assembly RH (Front driver side - side squib)

  • Center airbag sensor assembly
B1821/55

  • The center airbag sensor assembly receives an open circuit signal in the front driver side - side squib circuit.

  • Front driver side - side squib malfunction

  • Center airbag sensor assembly malfunction

    for LHD:

  • No. 2 floor wire

  • Front seat wire LH

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

  • Center airbag sensor assembly


    for RHD:

  • Floor wire

  • Front seat wire RH

  • Front seat side airbag assembly RH (Front driver side - side squib)

  • Center airbag sensor assembly
B1822/55

  • The center airbag sensor assembly receives a short circuit to ground signal in the front driver side - side squib circuit.

  • Front driver side - side squib malfunction

  • Center airbag sensor assembly malfunction

    for LHD:

  • No. 2 floor wire

  • Front seat wire LH

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

  • Center airbag sensor assembly


    for RHD:

  • Floor wire

  • Front seat wire RH

  • Front seat side airbag assembly RH (Front driver side - side squib)

  • Center airbag sensor assembly
B1823/55

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

  • Front driver side - side squib malfunction

  • Center airbag sensor assembly malfunction

    for LHD:

  • No. 2 floor wire

  • Front seat wire LH

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

  • Center airbag sensor assembly


    for RHD:

  • Floor wire

  • Front seat wire RH

  • Front seat side airbag assembly RH (Front driver side - side squib)

  • Center airbag sensor assembly

WIRING DIAGRAM

A01CFR8E01

INSPECTION PROCEDURE

Tech Tips


  • Perform the simulation method by selecting Check Mode (Signal Check) using the intelligent tester Click here.

  • After selecting Check Mode (Signal Check), perform the simulation method by wiggling each connector of the airbag system or driving the vehicle on a city or rough road Click here.

PROCEDURE


  1. CHECK CONNECTORS


    1. for LHD:


      1. Turn the engine switch off.

        A01CEX6E04

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

      3. Check that the connectors are properly connected to the front seat side airbag assembly LH and center airbag sensor assembly. Also check that the connectors that link the No. 2 floor wire and front seat wire LH are properly connected.

        OK
        The connectors are properly connected.

        Tech Tips

        If the connectors are not connected securely, reconnect the connectors and proceed to the next inspection.

      4. Disconnect the connectors from the front seat side airbag assembly LH and center airbag sensor assembly. Also disconnect the No. 2 floor wire from the front seat wire LH.

      5. Check that the terminals of the connectors are not damaged.

        OK
        The terminals are not deformed or damaged.

      6. Check that the short springs for the No. 2 floor wire and front seat wire LH with the activation prevention mechanism are not deformed or damaged.

        OK
        The short springs are not deformed or damaged.

    2. for RHD:


      1. Turn the engine switch off.

        A01CEX6E02

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

      3. Check that the connectors are properly connected to the front seat side airbag assembly RH and center airbag sensor assembly. Also check that the connectors that link the floor wire and front seat wire RH are properly connected.

        OK
        The connectors are properly connected.

        Tech Tips

        If the connectors are not connected securely, reconnect the connectors and proceed to the next inspection.

      4. Disconnect the connectors from the front seat side airbag assembly RH and center airbag sensor assembly. Also disconnect the floor wire from the front seat wire RH.

      5. Check that the terminals of the connectors are not damaged.

        OK
        The terminals are not deformed or damaged.

      6. Check that the short springs for the floor wire and front seat wire RH with the activation prevention mechanism are not deformed or damaged.

        OK
        The short springs are not deformed or damaged.

    NG

    REPLACE WIRE HARNESS

    OK

  2. CHECK FRONT SEAT SIDE AIRBAG ASSEMBLY (FRONT DRIVER SIDE - SIDE SQUIB)


    1. for LHD:


      1. Connect the No. 2 floor wire to the front seat wire LH and center airbag sensor assembly.

        A01CAPPE03

      2. Connect SST (resistance 2.1 Ω) to connector E.

        CAUTION:

        Never connect the tester to the front seat side airbag assembly LH (front driver side - side squib) 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.

        • Insert SST straight into the terminals of the connector.

      3. Connect the cable to the negative (-) battery terminal.

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

      5. Clear the DTCs stored in the memory Click here.

      6. Turn the engine switch off.

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

      8. Check for DTCs Click here.

        OK
        DTC B1820, B1821, B1822, B1823 or 55 is not output.

        Tech Tips

        Codes other than DTCs B1820, B1821, B1822, B1823 and 55 may be output at this time, but they are not related to this check.

        Result
        Result Proceed to
        NG A
        OK B
      SST
      09843-18061

    2. for RHD:


      1. Connect the floor wire to the front seat wire RH and center airbag sensor assembly.

        A01CAPPE01

      2. Connect SST (resistance 2.1 Ω) to connector E.

        CAUTION:

        Never connect the tester to the front seat side airbag assembly RH (front driver side - side squib) 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.

        • Insert SST straight into the terminals of the connector.

      3. Connect the cable to the negative (-) battery terminal.

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

      5. Clear the DTCs stored in the memory Click here.

      6. Turn the engine switch off.

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

      8. Check for DTCs Click here.

        OK
        DTC B1820, B1821, B1822, B1823 or 55 is not output.

        Tech Tips

        Codes other than DTCs B1820, B1821, B1822, B1823 and 55 may be output at this time, but they are not related to this check.

        Result
        Result Proceed to
        NG A
        OK C
      SST
      09843-18061

    B

    REPLACE FRONT SEAT SIDE AIRBAG ASSEMBLY LH Click here

    C

    REPLACE FRONT SEAT SIDE AIRBAG ASSEMBLY RH Click here

    A

  3. CHECK WIRE HARNESS (FRONT DRIVER SIDE - SIDE SQUIB CIRCUIT)


    1. for LHD:


      1. Turn the engine switch off.

        A01CCASE04

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

      3. Disconnect SST from connector E.

      4. Disconnect the No. 2 floor wire from the center airbag sensor assembly.

      5. Check for a short to B+ in the circuit.


        1. Connect the cable to the negative (-) battery terminal.

        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
          Wz1-1 (SFL+) - Body ground Engine switch on (IG) Below 1 V
          Wz1-2 (SFL-) - Body ground Engine switch on (IG) Below 1 V

      6. Check for an open in the circuit.


        1. Turn the engine switch off.

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

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

          Standard Resistance
          Tester Connection Condition Specified Condition
          Wz1-1 (SFL+) - Wz1-2 (SFL-) Always Below 1 Ω

      7. Check for a short to ground in the circuit.


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

          Standard Resistance
          Tester Connection Condition Specified Condition
          Wz1-1 (SFL+) - Body ground Always 1 MΩ or higher
          Wz1-2 (SFL-) - Body ground Always 1 MΩ or higher

      8. Check for a short in the circuit.


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

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

          Standard Resistance
          Tester Connection Condition Specified Condition
          Wz1-1 (SFL+) - Wz1-2 (SFL-) Always 1 MΩ or higher

    2. for RHD:


      1. Turn the engine switch off.

        A01CCASE01

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

      3. Disconnect SST from connector E.

      4. Disconnect the floor wire from the center airbag sensor assembly.

      5. Check for a short to B+ in the circuit.


        1. Connect the cable to the negative (-) battery terminal.

        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
          Vz1-1 (SFR+) - Body ground Engine switch on (IG) Below 1 V
          Vz1-2 (SFR-) - Body ground Engine switch on (IG) Below 1 V

      6. Check for an open in the circuit.


        1. Turn the engine switch off.

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

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

          Standard Resistance
          Tester Connection Condition Specified Condition
          Vz1-1 (SFR+) - Vz1-2 (SFR-) Always Below 1 Ω

      7. Check for a short to ground in the circuit.


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

          Standard Resistance
          Tester Connection Condition Specified Condition
          Vz1-1 (SFR+) - Body ground Always 1 MΩ or higher
          Vz1-2 (SFR-) - Body ground Always 1 MΩ or higher

      8. Check for a short in the circuit.


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

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

          Standard Resistance
          Tester Connection Condition Specified Condition
          Vz1-1 (SFR+) - Vz1-2 (SFR-) Always 1 MΩ or higher

    NG

    CHECK WIRE HARNESS Click here

    OK

  4. CHECK CENTER AIRBAG SENSOR ASSEMBLY


    1. A01CBWDE01

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

    2. for LHD:

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

    3. for RHD:

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

    4. Connect the cable to the negative (-) battery terminal.

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

    6. Clear the DTCs stored in the memory Click here.

    7. Turn the engine switch off.

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

    9. Check for DTCs Click here.

      OK
      DTC B1820, B1821, B1822, B1823 or 55 is not output.

      Tech Tips

      Codes other than DTCs B1820, B1821, B1822, B1823 and 55 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 WIRE HARNESS


    1. for LHD:


      1. Restore the release activation prevention mechanism of connector B to the original condition.

        A01CG19E03

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

      3. Check for a short to B+ in the circuit.


        1. Connect the cable to the negative (-) battery terminal.

        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
          NW2-1 (SFL+) - Body ground Engine switch on (IG) Below 1 V
          NW2-2 (SFL-) - Body ground Engine switch on (IG) Below 1 V

      4. Check for an open in the circuit.


        1. Turn the engine switch off.

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

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

          Standard Resistance
          Tester Connection Condition Specified Condition
          NW2-1 (SFL+) - NW2-2 (SFL-) Always Below 1 Ω

      5. Check for a short to ground in the circuit.


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

          Standard Resistance
          Tester Connection Condition Specified Condition
          NW2-1 (SFL+) - Body ground Always 1 MΩ or higher
          NW2-2 (SFL-) - Body ground Always 1 MΩ or higher

      6. Check for a short in the circuit.


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

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

          Standard Resistance
          Tester Connection Condition Specified Condition
          NW2-1 (SFL+) - NW2-2 (SFL-) Always 1 MΩ or higher
          Result
          Result Proceed to
          OK A
          NG B

    2. for RHD:


      1. Restore the release activation prevention mechanism of connector B to the original condition.

        A01CG19E01

      2. Disconnect the front seat wire RH from the floor wire.

      3. Check for a short to B+ in the circuit.


        1. Connect the cable to the negative (-) battery terminal.

        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
          MV2-1 (SFR+) - Body ground Engine switch on (IG) Below 1 V
          MV2-2 (SFR-) - Body ground Engine switch on (IG) Below 1 V

      4. Check for an open in the circuit.


        1. Turn the engine switch off.

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

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

          Standard Resistance
          Tester Connection Condition Specified Condition
          MV2-1 (SFR+) - MV2-2 (SFR-) Always Below 1 Ω

      5. Check for a short to ground in the circuit.


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

          Standard Resistance
          Tester Connection Condition Specified Condition
          MV2-1 (SFR+) - Body ground Always 1 MΩ or higher
          MV2-2 (SFR-) - Body ground Always 1 MΩ or higher

      6. Check for a short in the circuit.


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

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

          Standard Resistance
          Tester Connection Condition Specified Condition
          MV2-1 (SFR+) - MV2-2 (SFR-) Always 1 MΩ or higher
          Result
          Result Proceed to
          OK A
          NG C

    B

    REPLACE NO. 2 FLOOR WIRE

    C

    REPLACE FLOOR WIRE

    A

  6. CHECK WIRE HARNESS


    1. for LHD:


      1. Check for a short to B+ in the circuit.

        A01CFURE03

        1. Connect the cable to the negative (-) battery terminal.

        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
          Wz1-1 (SFL+) - Body ground Engine switch on (IG) Below 1 V
          Wz1-2 (SFL-) - Body ground Engine switch on (IG) Below 1 V

      2. Check for an open in the circuit.


        1. Turn the engine switch off.

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

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

          Standard Resistance
          Tester Connection Condition Specified Condition
          Wz1-1 (SFL+) - Wz1-2 (SFL-) Always Below 1 Ω

      3. Check for a short to ground in the circuit.


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

          Standard Resistance
          Tester Connection Condition Specified Condition
          Wz1-1 (SFL+) - Body ground Always 1 MΩ or higher
          Wz1-2 (SFL-) - Body ground Always 1 MΩ or higher

      4. Check for a short in the circuit.


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

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

          Standard Resistance
          Tester Connection Condition Specified Condition
          Wz1-1 (SFL+) - Wz1-2 (SFL-) Always 1 MΩ or higher
          Result
          Result Proceed to
          OK A
          NG B

    2. for RHD:


      1. Check for a short to B+ in the circuit.

        A01CFURE01

        1. Connect the cable to the negative (-) battery terminal.

        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
          Vz1-1 (SFR+) - Body ground Engine switch on (IG) Below 1 V
          Vz1-2 (SFR-) - Body ground Engine switch on (IG) Below 1 V

      2. Check for an open in the circuit.


        1. Turn the engine switch off.

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

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

          Standard Resistance
          Tester Connection Condition Specified Condition
          Vz1-1 (SFR+) - Vz1-2 (SFR-) Always Below 1 Ω

      3. Check for a short to ground in the circuit.


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

          Standard Resistance
          Tester Connection Condition Specified Condition
          Vz1-1 (SFR+) - Body ground Always 1 MΩ or higher
          Vz1-2 (SFR-) - Body ground Always 1 MΩ or higher

      4. Check for a short in the circuit.


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

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

          Standard Resistance
          Tester Connection Condition Specified Condition
          Vz1-1 (SFR+) - Vz1-2 (SFR-) Always 1 MΩ or higher
          Result
          Result Proceed to
          OK A
          NG C

    B

    REPLACE FRONT SEAT WIRE LH

    C

    REPLACE FRONT SEAT WIRE RH

    A

    USE SIMULATION METHOD TO CHECK Click here