LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Toyota >> 2012 >> Matrix Base, Standard Trans >> Repair and Diagnosis (Single Page) >> Restraints >> Restraints Control Systems >> Supplemental Restraint System (Diagnostic Codes (B1000 - B1974) & Symptom Tests) >> Airbag System >> DTC B1815/54: Short in Front Passenger Side Squib 2nd Step Circuit; DTC B1816/54: Open in Front Passenger Side Squib 2nd Step Circuit; DTC B1817/54: Short to GND in Front Passenger Side Squib 2nd Step Circuit; DTC B1818/54: Short to B+ in Front Passenger Side Squib 2nd Step Circuit >> Procedure
April 5, 2026: LEMON Manuals is launched! Read the announcement.

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

  1. CHECK CONNECTORS 
    1. Turn the ignition switch off.
      Fig 1: Checking Connectors
      GTY124832Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    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 passenger airbag assembly and center airbag sensor assembly. Also check that the connectors that link the instrument panel wire assembly and instrument panel wire are properly connected.

      OK

      The connectors are properly connected.

      HINT: 

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

    4. Disconnect the connectors from the front passenger airbag assembly and center airbag sensor assembly. Also disconnect the instrument panel wire from the instrument panel wire assembly.
    5. Check that the terminals of the connectors are not damaged.

      OK

      The terminals are not deformed or damaged.

    6. Check that the instrument panel wire assembly connector (on the front passenger airbag assembly side) is not damaged.

      OK

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

    7. Check that the short springs for the instrument panel wire and instrument panel wire assembly with the activation prevention mechanism are not deformed or damaged.

      OK

      The short springs are not deformed or damaged.

    NG → REPLACE WIRE HARNESS 

    OK: Go to next step 

  2. CHECK FRONT PASSENGER AIRBAG ASSEMBLY (FRONT PASSENGER SIDE SQUIB 2ND STEP) 
    1. Connect the instrument panel wire to the instrument panel wire assembly and center airbag sensor assembly.
      Fig 2: Checking Front Passenger Airbag Assembly Using SST (Front Passenger Side Squib 2nd Step)
      GTY244479Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Connect SST (resistance 2.1 Ω) to connector E (black connector).
      WARNING:

      Never connect a tester to the front passenger airbag assembly (front passenger 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.
      • Insert SST straight into the terminals of the connector.
      • SST: 09843-18061 
    3. Connect the cable to the negative (-) battery terminal.
    4. Turn the ignition switch to ON, and wait for at least 60 seconds.
    5. Clear the DTCs stored in the memory. Refer to DTC CHECK / CLEAR .
    6. Turn the ignition switch off.
    7. Turn the ignition switch to ON, and wait for at least 60 seconds.
    8. Check for DTCs. Refer to DTC CHECK / CLEAR .

      OK

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

      HINT: 

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

    NG → See step   4 

    OK → See step   3 

  3. REPLACE FRONT PASSENGER AIRBAG ASSEMBLY. Refer to  REMOVAL 
  4. CHECK FRONT PASSENGER SIDE SQUIB 2ND STEP CIRCUIT 
    1. Turn the ignition switch off.
      Fig 3: Checking Front Passenger Side Squib 2nd Step Circuit And T2 Connector Terminals
      GTY225214Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    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 instrument panel 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 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
        T2-2 (P2+) - Body ground Ignition switch ON Below 1 V
        T2-1 (P2-) - Body ground Ignition switch ON Below 1 V
    6. Check for an open in the circuit.
      1. Turn the ignition 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
        T2-2 (P2+) - T2-1 (P2-) 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
        T2-2 (P2+) - Body ground Always 1 MΩ or higher
        T2-1 (P2-) - 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. Refer to DIAGNOSIS SYSTEM .
      2. Measure the resistance according to the value(s) in the table below.

        Standard Resistance

        Tester Connection Condition Specified Condition
        T2-2 (P2+) - T2-1 (P2-) Always 1 MΩ or higher

    NG → See step   6 

    OK: Go to next step 

  5. CHECK CENTER AIRBAG SENSOR ASSEMBLY 
    1. Restore the released activation prevention mechanism of connector B to the original condition.
      Fig 4: Checking Center Airbag Sensor Assembly
      GTY109759Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Connect the connectors to the front passenger airbag assembly and the center airbag sensor assembly.
    3. Connect the cable to the negative (-) battery terminal.
    4. Turn the ignition switch to ON, and wait for at least 60 seconds.
    5. Clear the DTCs stored in the memory. Refer to DTC CHECK / CLEAR .
    6. Turn the ignition switch off.
    7. Turn the ignition switch to ON, and wait for at least 60 seconds.
    8. Check for DTCs. Refer to DTC CHECK / CLEAR .

      OK

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

      HINT: 

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

    NG → See step   8 

    OK → See step   9 

  6. CHECK INSTRUMENT PANEL WIRE 
    1. Restore the released activation prevention mechanism of connector B to the original condition.
      Fig 5: Checking Instrument Panel Wire And ET1 Connector Terminals
      GTY244384Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Disconnect the instrument panel wire assembly from the instrument panel wire.
    3. 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 Switch Condition Specified Condition
        ET1-3 (P2+) - Body ground Ignition switch ON Below 1 V
        ET1-4 (P2-) - Body ground Ignition switch ON Below 1 V
    4. Check for an open in the circuit.
      1. Turn the ignition 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
        ET1-3 (P2+) - ET1-4 (P2-) 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
        ET1-3 (P2+) - Body ground Always 1 MΩ or higher
        ET1-4 (P2-) - 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. Refer to DIAGNOSIS SYSTEM .
      2. Measure the resistance according to the value(s) in the table below.

        Standard Resistance

        Tester Connection Condition Specified Condition
        ET1-3 (P2+) - ET1-4 (P2-) Always 1 MΩ or higher

    NG → REPLACE INSTRUMENT PANEL WIRE 

    OK: Go to next step 

  7. CHECK INSTRUMENT PANEL WIRE ASSEMBLY 
    1. Check for a short to B+ in the circuit.
      Fig 6: Checking Instrument Panel Wire Assembly And T2 Connector Terminals
      GTY222453Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      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 Switch Condition Specified Condition
        T2-2 (P2+) - Body ground Ignition switch ON Below 1 V
        T2-1 (P2-) - Body ground Ignition switch ON Below 1 V
    2. Check for an open in the circuit.
      1. Turn the ignition 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
        T2-2 (P2+) - T2-1 (P2-) 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
        T2-2 (P2+) - Body ground Always 1 MΩ or higher
        T2-1 (P2-) - 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. Refer to DIAGNOSIS SYSTEM .
      2. Measure the resistance according to the value(s) in the table below.

        Standard Resistance

        Tester Connection Condition Specified Condition
        T2-2 (P2+) - T2-1 (P2-) Always 1 MΩ or higher

    NG → REPLACE INSTRUMENT PANEL WIRE ASSEMBLY 

    OK → See step   9 

  8. REPLACE CENTER AIRBAG SENSOR ASSEMBLY. Refer to  REMOVAL 
  9. USE SIMULATION METHOD TO CHECK. Refer to  DIAGNOSIS SYSTEM 
scientia non olet · About LEMON Manuals