AIRBAG SYSTEM, Diagnostic DTC:B1815, B1816, B1817, B1818

DTC Code DTC Name
B1815 Short in P Squib (Dual Stage - 2nd Step) Circuit
B1816 Open in P Squib (Dual Stage - 2nd Step) Circuit
B1817 Short in P Squib (Dual Stage - 2nd Step) Circuit (to Ground)
B1818 Short in P Squib (Dual Stage - 2nd Step) Circuit (to +B)

DESCRIPTION

The front passenger side squib 2nd step circuit consists of the airbag ECU assembly and instrument panel passenger airbag assembly.

The airbag ECU assembly uses this circuit to deploy the airbag when deployment conditions are met.

These DTCs are stored when a malfunction is detected in the front passenger side squib 2nd step circuit.

DTC No. DTC Detection Condition Trouble Area
B1815

  • The airbag ECU assembly receives a line short circuit signal in the front passenger side squib 2nd step circuit during primary check.

  • Front passenger side squib 2nd step malfunction

  • Airbag ECU assembly malfunction

  • Instrument panel wire

  • Instrument panel passenger airbag assembly (Front passenger side squib 2nd step)

  • Airbag ECU assembly
B1816

  • The airbag ECU assembly receives an open circuit signal in the front passenger side squib 2nd step circuit.

  • Front passenger side squib 2nd step malfunction

  • Airbag ECU assembly malfunction
B1817

  • The airbag ECU assembly receives a short circuit to ground signal in the front passenger side squib 2nd step circuit.

  • Front passenger side squib 2nd step malfunction

  • Airbag ECU assembly malfunction
B1818

  • The airbag ECU assembly receives a short circuit to B+ signal in the front passenger side squib 2nd step circuit.

  • Front passenger side squib 2nd step malfunction

  • Airbag ECU assembly malfunction

WIRING DIAGRAM

A004HCBE02
*a Instrument Panel Passenger Airbag Assembly (Front Passenger Side Squib)
*b Airbag ECU 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.

Tech Tips


  • Perform the simulation method by selecting check mode (Signal Check) using the GTS 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 road or rough road Click here.

PROCEDURE


  1. CHECK CONNECTORS


    1. A004KKWE01
      Text in Illustration
      *1 Instrument Panel Passenger Airbag Assembly
      *2 Airbag ECU Assembly
      *3 Instrument Panel Wire

      Turn the ignition switch off.

    2. Disconnect the cable from the negative (-) battery terminal.

      CAUTION:

      Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to disable the SRS system.

    3. Check that the connectors are properly connected to the instrument panel passenger airbag assembly and airbag ECU assembly.

      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 instrument panel passenger airbag assembly and airbag ECU assembly.

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

      OK
      The terminals are not deformed or damaged.

    6. Check that the short spring for the instrument panel wire with the activation prevention mechanism are not deformed or damaged.

      OK
      The short spring is not deformed or damaged.

    NG

    REPLACE INSTRUMENT PANEL WIRE

    OK

  2. CHECK INSTRUMENT PANEL PASSENGER AIRBAG ASSEMBLY (FRONT PASSENGER SIDE SQUIB 2ND STEP)


    1. A004HM7E02
      Text in Illustration
      *1 Instrument Panel Passenger Airbag Assembly
      *2 Airbag ECU Assembly
      *a

      Front view of wire harness connector

      (to Instrument Panel Passenger Airbag Assembly)

      Connect the connector to the airbag ECU assembly.

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

      CAUTION:

      Never connect the tester to the instrument panel passenger airbag assembly (front passenger side squib 2nd step) 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 it.

      • Insert SST straight into the terminals of the connector.

      SST
      09843-18061

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

    4. Clear the DTCs stored in memory Click here.

    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.

      OK
      DTC B1815, B1816, B1817 or B1818 is not output.

      Tech Tips

      Codes other than DTCs B1815, B1816, B1817 and B1818 may be output at this time, but they are not related to this check.

    8. Turn the ignition switch off.

    9. Disconnect the cable from the negative (-) battery terminal.

      CAUTION:

      Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to disable the SRS system.

    10. Disconnect SST from connector C.


    OK

    REPLACE INSTRUMENT PANEL PASSENGER AIRBAG ASSEMBLY Click here

    NG

  3. CHECK FRONT PASSENGER SIDE SQUIB 2ND STEP CIRCUIT


    1. A004J7GE02
      Text in Illustration
      *1 Instrument Panel Passenger Airbag Assembly
      *2 Airbag ECU Assembly
      *3 Instrument Panel Wire
      *a

      Front view of wire harness connector

      (to Instrument Panel Passenger Airbag Assembly)

      Disconnect the instrument panel wire from the airbag ECU assembly.

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


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

      2. Turn the ignition switch to ON.

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

        Standard Voltage
        Tester Connection Condition Specified Condition
        D30-4 (P2+) - Body ground Ignition switch ON Below 1 V
        D30-3 (P2-) - Body ground Ignition switch ON Below 1 V

      4. Turn the ignition switch off.

      5. Disconnect the cable from the negative (-) battery terminal.

        CAUTION:

        Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to disable the SRS system.

    3. Check for an open in the circuit.


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

        Standard Resistance
        Tester Connection Condition Specified Condition
        D30-4 (P2+) - D30-3 (P2-) Always Below 1 Ω

    4. 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
        D30-4 (P2+) - Body ground Always 1 MΩ or higher
        D30-3 (P2-) - Body ground Always 1 MΩ or higher

    5. 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
        D30-4 (P2+) - D30-3 (P2-) Always 1 MΩ or higher

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


    NG

    REPLACE INSTRUMENT PANEL WIRE

    OK

  4. CHECK DTC


    1. A004H6WE01
      Text in Illustration
      *1 Instrument Panel Passenger Airbag Assembly
      *2 Airbag ECU Assembly

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

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

    3. Clear the DTCs stored in memory Click here.

    4. Turn the ignition switch off.

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

    6. Check for DTCs Click here.

      OK
      DTC B1815, B1816, B1817 or B1818 is not output.

      Tech Tips

      Codes other than DTCs B1815, B1816, B1817 and B1818 may be output at this time, but they are not related to this check.


    OK

    USE SIMULATION METHOD TO CHECK Click here

    NG

    REPLACE AIRBAG ECU ASSEMBLY Click here