AIRBAG SYSTEM(for Type C), Diagnostic DTC:B181A/7A, B181B/7A, B181C/7A, B181D/7A

DTC Code DTC Name
B181A/7A Short in Passenger Side Airbag Variable Vent Hole Squib Circuit
B181B/7A Open in Passenger Side Airbag Variable Vent Hole Squib Circuit
B181C/7A Short to GND in Passenger Side Airbag Variable Vent Hole Squib Circuit
B181D/7A Short to B+ in Passenger Side Airbag Variable Vent Hole Squib Circuit

DESCRIPTION

The front passenger side airbag variable vent hole squib circuit consists of the airbag sensor assembly and instrument panel passenger airbag assembly.

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

These DTCs are stored when a malfunction is detected in the front passenger side airbag variable vent hole squib circuit.

DTC No. Detection Item DTC Detection Condition Trouble Area
B181A/7A Short in Passenger Side Airbag Variable Vent Hole Squib Circuit

One of the following conditions is met:


  • The airbag sensor assembly detects a line short circuit signal 5 times in the front passenger side airbag variable vent hole squib circuit during the primary check.

  • An instrument panel passenger airbag assembly malfunction.

  • An airbag sensor assembly malfunction.

  • Instrument panel wire

  • No. 2 instrument panel wire

  • Instrument panel passenger airbag assembly

  • Airbag sensor assembly
B181B/7A Open in Passenger Side Airbag Variable Vent Hole Squib Circuit

One of the following conditions is met:


  • The airbag sensor assembly detects an open circuit signal in the front passenger side airbag variable vent hole squib circuit for 2 seconds.

  • An instrument panel passenger airbag assembly malfunction.

  • An airbag sensor assembly malfunction.

  • Instrument panel wire

  • No. 2 instrument panel wire

  • Instrument panel passenger airbag assembly

  • Airbag sensor assembly
B181C/7A Short to GND in Passenger Side Airbag Variable Vent Hole Squib Circuit

One of the following conditions is met:


  • The airbag sensor assembly detects a short circuit to ground signal in the front passenger side airbag variable vent hole squib circuit for 0.5 seconds.

  • An instrument panel passenger airbag assembly malfunction.

  • An airbag sensor assembly malfunction.

  • Instrument panel wire

  • No. 2 instrument panel wire

  • Instrument panel passenger airbag assembly

  • Airbag sensor assembly
B181D/7A Short to B+ in Passenger Side Airbag Variable Vent Hole Squib Circuit

One of the following conditions is met:


  • The airbag sensor assembly detects a short circuit to B+ signal in the front passenger side airbag variable vent hole squib circuit for 0.5 seconds.

  • An instrument panel passenger airbag assembly malfunction.

  • An airbag sensor assembly malfunction.

  • Instrument panel wire

  • No. 2 instrument panel wire

  • Instrument panel passenger airbag assembly

  • Airbag sensor assembly

WIRING DIAGRAM

B0025MGE49
*a Airbag Sensor Assembly
*b Instrument Panel Passenger Airbag Assembly

CAUTION / NOTICE / HINT

Note


  • After turning the ignition 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

  • After replacing the airbag sensor assembly, refer to initialization.

    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 INSTRUMENT PANEL PASSENGER AIRBAG ASSEMBLY


    1. B0026R5C01
      *1 Instrument Panel Passenger Airbag Assembly
      *2 Airbag Sensor Assembly
      *3 Connector E
      *4 SST
      *a

      Front view of wire harness connector

      (to Instrument Panel Passenger Airbag Assembly)
      *b Color: Green

      Turn the ignition switch off.

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

    3. Disconnect the connector from the instrument panel passenger airbag assembly.

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

      CAUTION:

      Never connect the tester to the instrument panel passenger airbag assembly 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 ignition switch to ON, and wait for at least 60 seconds.

    7. Clear the DTCs.

      Click here


      Body Electrical > SRS Airbag > Clear DTCs

    8. Turn the ignition switch off.

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

    10. Check for DTCs.

      Click here


      Body Electrical > SRS Airbag > Trouble Codes
      Result
      Proceed to
      DTC B181A/7A, B181B/7A, B181C/7A or B181D/7A is not output
      DTC B181A/7A, B181B/7A, B181C/7A or B181D/7A is output

      Tech Tips

      Codes other than DTC B1805/52, B1806/52, B1807/52 and B1808/52 may be output at this time, but they are not related to this check.

    11. Turn the ignition switch off.

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

    13. Disconnect SST from connector E.


    DTC B181A/7A, B181B/7A, B181C/7A or B181D/7A is not output

    REPLACE INSTRUMENT PANEL PASSENGER AIRBAG ASSEMBLY Click here

    DTC B181A/7A, B181B/7A, B181C/7A or B181D/7A is output

  2. CHECK CONNECTORS


    1. Disconnect the connectors from the airbag sensor assembly.

    2. B0024DJC03
      *1 Instrument Panel Passenger Airbag Assembly
      *2 Airbag Sensor Assembly
      *3 No. 2 Instrument Panel Wire
      *4 Instrument Panel Wire

      Check that the connectors (on the airbag sensor assembly side and instrument panel passenger airbag assembly side) are not damaged.

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

    NG

    REPLACE INSTRUMENT PANEL WIRE OR NO. 2 INSTRUMENT PANEL WIRE

    OK

  3. CHECK FRONT PASSENGER SIDE SQUIB CIRCUIT


    1. B0026A3C01
      *1 Instrument Panel Passenger Airbag Assembly
      *2 Airbag Sensor Assembly
      *3 Connector E
      *a

      Front view of wire harness connector

      (to Instrument Panel Passenger Airbag Assembly)
      *b Color: Green

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

    2. Turn the ignition switch to ON.

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      H6-1 (VHP+) - Body ground Ignition switch ON Below 1 V
      H6-2 (VHP-) - Body ground Ignition switch ON Below 1 V

    4. Turn the ignition 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
      H6-1 (VHP+) - H6-2 (VHP-) 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
      H6-1 (VHP+) - H6-2 (VHP-) Always 1 MΩ or higher

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

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      H6-1 (VHP+) - Body ground Always 1 MΩ or higher
      H6-2 (VHP-) - Body ground Always 1 MΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    CHECK INSTRUMENT PANEL WIRE Click here

    OK

  4. CHECK DTC


    1. B0024JNC08
      *1 Instrument Panel Passenger Airbag Assembly
      *2 Airbag Sensor Assembly

      Connect the connectors to the instrument panel passenger airbag assembly and airbag sensor assembly.

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

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

    4. Clear the DTCs.

      Click here


      Body Electrical > SRS Airbag > Clear DTCs

    5. Turn the ignition switch off.

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

    7. Check for DTCs.

      Click here


      Body Electrical > SRS Airbag > Trouble Codes
      Result
      Proceed to
      DTC B181A/7A, B181B/7A, B181C/7A or B181D/7A is not output
      DTC B181A/7A, B181B/7A, B181C/7A or B181D/7A is output

      Tech Tips

      Codes other than DTC B1805/52, B1806/52, B1807/52 and B1808/52 may be output at this time, but they are not related to this check.


    DTC B181A/7A, B181B/7A, B181C/7A or B181D/7A is not output

    USE SIMULATION METHOD TO CHECK Click here

    DTC B181A/7A, B181B/7A, B181C/7A or B181D/7A is output

    REPLACE AIRBAG SENSOR ASSEMBLY Click here

  5. CHECK INSTRUMENT PANEL WIRE


    1. B00265NC07
      *1 Instrument Panel Passenger Airbag Assembly
      *2 No. 2 Instrument Panel Wire
      *3 Instrument Panel Wire
      *4 Airbag Sensor Assembly
      *5 Connector C
      *a

      Front view of wire harness connector

      (to No. 2 Instrument Panel Wire)

      Disconnect the instrument panel wire connector from the No. 2 instrument panel wire.

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

    3. Turn the ignition switch to ON.

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      GH2-2 (VHP+) - Body ground Ignition switch ON Below 1 V
      GH2-1 (VHP-) - Body ground Ignition switch ON Below 1 V

    5. Turn the ignition 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
      GH2-2 (VHP+) - GH2-1 (VHP-) 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
      GH2-2 (VHP+) - GH2-1 (VHP-) Always 1 MΩ or higher

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

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      GH2-2 (VHP+) - Body ground Always 1 MΩ or higher
      GH2-1 (VHP-) - Body ground Always 1 MΩ or higher
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE NO. 2 INSTRUMENT PANEL WIRE

    NG

    REPLACE INSTRUMENT PANEL WIRE