AIRBAG SYSTEM, Diagnostic DTC:B1815/54, B1816/54, B1817/54, B1818/54

DTC Code DTC Name
B1815/54 Short in Front Passenger Side Squib 2nd Step Circuit
B1816/54 Open in Front Passenger Side Squib 2nd Step Circuit
B1817/54 Short to GND in Front Passenger Side Squib 2nd Step Circuit
B1818/54 Short to B+ in Front Passenger Side Squib 2nd Step Circuit

DESCRIPTION

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

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 squib 2nd step circuit.

DTC No. Detection Item DTC Detection Condition Trouble Area
B1815/54 Short in Front Passenger Side Squib 2nd Step Circuit

    One of the following conditions is met:

  • The airbag ECU assembly detects a line short circuit signal 5 times in the front passenger side squib 2nd step circuit during the primary check.

  • An instrument panel passenger airbag assembly (front passenger side squib 2nd step) malfunction.

  • An airbag ECU assembly malfunction.

  • Instrument panel wire

  • No. 2 instrument panel wire

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

  • Airbag ECU assembly
B1816/54 Open in Front Passenger Side Squib 2nd Step Circuit

    One of the following conditions is met:

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

  • An instrument panel passenger airbag assembly (front passenger side squib 2nd step) malfunction.

  • An airbag ECU assembly malfunction.

  • Instrument panel wire

  • No. 2 instrument panel wire

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

  • Airbag ECU assembly
B1817/54 Short to GND in Front Passenger Side Squib 2nd Step Circuit

    One of the following conditions is met:

  • The airbag ECU assembly detects a short circuit to ground signal in the front passenger side squib 2nd step circuit for 0.5 seconds.

  • An instrument panel passenger airbag assembly (front passenger side squib 2nd step) malfunction.

  • An airbag ECU assembly malfunction.

  • Instrument panel wire

  • No. 2 instrument panel wire

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

  • Airbag ECU assembly
B1818/54 Short to B+ in Front Passenger Side Squib 2nd Step Circuit

    One of the following conditions is met:

  • The airbag ECU assembly detects a short circuit to B+ signal in the front passenger side squib 2nd step circuit for 0.5 seconds.

  • An instrument panel passenger airbag assembly (front passenger side squib 2nd step) malfunction.

  • An airbag ECU assembly malfunction.

  • Instrument panel wire

  • No. 2 instrument panel wire

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

  • Airbag ECU assembly

WIRING DIAGRAM

B005A1AE32
*a Instrument Panel Passenger Airbag Assembly (Front Passenger Side Squib 2nd Step)
*b Airbag ECU Assembly

CAUTION / NOTICE / HINT

Note


  • After turning the engine 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 ECU 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 (FRONT PASSENGER SIDE SQUIB 2ND STEP)


    1. B005AHQC07
      *1 Instrument Panel Passenger Airbag Assembly (Front Passenger Side Squib 2nd Step)
      *2 Airbag ECU Assembly
      *3 Connector E
      *4 SST
      *a

      Front view of wire harness connector

      (to Instrument Panel Passenger Airbag Assembly [Front Passenger Side Squib 2nd Step])
      *b Color: Black

      Turn the engine 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 (black connector).

      CAUTION:

      Never connect the tester to the instrument panel passenger (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 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 engine switch on (IG), and wait for at least 60 seconds.

    7. Clear the DTCs.

      Click here


      Body Electrical > SRS Airbag > Clear DTCs

    8. Turn the engine switch off.

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

    10. Check for DTCs.

      Click here


      Body Electrical > SRS Airbag > Trouble Codes
      Result
      Proceed to
      DTC B1815/54, B1816/54, B1817/54 or B1818/54 is not output
      DTC B1815/54, B1816/54, B1817/54 or B1818/54 is output

      Tech Tips

      Codes other than DTC B1815/54, B1816/54, B1817/54 and B1818/54 may be output at this time, but they are not related to this check.

    11. Turn the engine 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 B1815/54, B1816/54, B1817/54 or B1818/54 is not output

    REPLACE INSTRUMENT PANEL PASSENGER AIRBAG ASSEMBLY Click here

    DTC B1815/54, B1816/54, B1817/54 or B1818/54 is output

  2. CHECK CONNECTORS


    1. Disconnect the connectors from the airbag ECU assembly.

    2. B0057TLC07
      *1 Instrument Panel Passenger Airbag Assembly (Front Passenger Side Squib 2nd Step)
      *2 Airbag ECU Assembly
      *3 No. 2 Instrument Panel Wire
      *4 Instrument Panel Wire

      Check that the connectors (on the airbag ECU 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 damaged or deformed.
      Result
      Proceed to
      OK
      NG

    NG

    REPLACE INSTRUMENT PANEL WIRE OR NO. 2 INSTRUMENT PANEL WIRE

    OK

  3. CHECK FRONT PASSENGER SIDE SQUIB 2ND STEP CIRCUIT


    1. B0059CEC09
      *1 Instrument Panel Passenger Airbag Assembly (Front Passenger Side Squib 2nd Step)
      *2 Airbag ECU Assembly
      *3 Connector E
      *a

      Front view of wire harness connector

      (to Instrument Panel Passenger Airbag Assembly [Front Passenger Side Squib 2nd Step])
      *b Color: Black

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

    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
      H1-2 (P2+) - Body ground Engine switch on (IG) Below 1 V
      H1-1 (P2-) - Body ground Engine switch on (IG) Below 1 V

    4. Turn the engine 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
      H1-2 (P2+) - H1-1 (P2-) 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
      H1-2 (P2+) -H1-1 (P2-) 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
      H1-2 (P2+) - Body ground Always 1 MΩ or higher
      H1-1 (P2-) - Body ground Always 1 MΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    CHECK INSTRUMENT PANEL WIRE Click here

    OK

  4. CHECK DTC


    1. B005AGLC09
      *1 Instrument Panel Passenger Airbag Assembly (Front Passenger Side Squib 2nd Step)
      *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, and wait for at least 2 seconds.

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

    4. Clear the DTCs.

      Click here


      Body Electrical > SRS Airbag > Clear DTCs

    5. Turn the engine switch off.

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

    7. Check for DTCs.

      Click here


      Body Electrical > SRS Airbag > Trouble Codes
      Result
      Proceed to
      DTC B1815/54, B1816/54, B1817/54 or B1818/54 is not output
      DTC B1815/54, B1816/54, B1817/54 or B1818/54 is output

      Tech Tips

      Codes other than DTC B1815/54, B1816/54, B1817/54 and B1818/54 may be output at this time, but they are not related to this check.


    DTC B1815/54, B1816/54, B1817/54 or B1818/54 is not output

    USE SIMULATION METHOD TO CHECK Click here

    DTC B1815/54, B1816/54, B1817/54 or B1818/54 is output

    REPLACE AIRBAG ECU ASSEMBLY Click here

  5. CHECK INSTRUMENT PANEL WIRE


    1. B005928C04
      *1 Instrument Panel Passenger Airbag Assembly (Front Passenger Side Squib 2nd Step)
      *2 No. 2 Instrument Panel Wire
      *3 Instrument Panel Wire
      *4 Airbag ECU 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 engine switch on (IG).

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      IH1-3 (P2+) - Body ground Engine switch on (IG) Below 1 V
      IH1-4 (P2-) - Body ground Engine switch on (IG) Below 1 V

    5. Turn the engine 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
      IH1-3 (P2+) - IH1-4 (P2-) 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
      IH1-3 (P2+) - IH1-4 (P2-) 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
      IH1-3 (P2+) - Body ground Always 1 MΩ or higher
      IH1-4 (P2-) - Body ground Always 1 MΩ or higher
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE NO. 2 INSTRUMENT PANEL WIRE

    NG

    REPLACE INSTRUMENT PANEL WIRE