ENGINE IMMOBILISER SYSTEM(w/ Entry and Start System), Diagnostic DTC:B279A

DTC Code DTC Name
B279A Theft Deterrent System Communication Line High Fixation

DESCRIPTION

If the communication line (EFIO-IMI) to the ID code box (immobiliser code ECU) is stuck on HI output, the ECM outputs this DTC.

DTC Code DTC Detection Condition Trouble Area
B279A When the communication line (EFIO-IMI) between the ECM and the ID code box (immobiliser code ECU) is stuck on HI output.

  • Harness or connector

  • ID code box (immobiliser code ECU)

  • ECM

WIRING DIAGRAM

A01X0Q7E06
A01X0Q7E05
A01XAN0E01
for 3UR-FE
*a from IMB Fuse
*b ID Code Box (Immobiliser Code ECU)

PROCEDURE


  1. CLEAR DTC


    1. Clear the DTCs Click here.


    NEXT

  2. CHECK FOR DTC


    1. Check for DTCs Click here.

      Tech Tips

      If DTCs other than DTC B279A are output, troubleshoot those DTCs first.

      Result
      Result Proceed to
      DTC B279A is output A
      DTC B279A and other DTCs are output B

    B

    Go to DIAGNOSTIC TROUBLE CODE CHART Click here

    A

  3. CHECK HARNESS AND CONNECTOR (ID CODE BOX (IMMOBILISER CODE ECU) - ECM)


    1. Disconnect the E28 ID code box connector.

      A01X5VLE04

    2. Disconnect the A38*1 or A52*2 ECU connector.

      Tech Tips


      • *1: for LHD

      • *2: for RHD

      A01X5VLE05

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


      1. for 1UR-FE

        Standard Resistance
        Tester Connection Condition Specified Condition
        E28-6 (EFIO) - A38*1-40 (IMI) Always Below 1 Ω
        E28-6 (EFIO) or A38*1-40 (IMI) - Body ground Always 10 kΩ or higher
        E28-6 (EFIO) - A52*2-40 (IMI) Always Below 1 Ω
        E28-6 (EFIO) or A52*2-40 (IMI) - Body ground Always 10 kΩ or higher

        Tech Tips


        • *1: for LHD

        • *2: for RHD

        Standard Voltage
        Tester Connection Condition Specified Condition
        E28-6 (EFIO) - Body ground Always Below 1 V
        A38*1-40 (IMI) - Body ground
        A52*2-40 (IMI) - Body ground

        Tech Tips


        • *1: for LHD

        • *2: for RHD

      2. for 1GR-FE, 1VD-FTV

        Standard Resistance
        Tester Connection Condition Specified Condition
        E28-6 (EFIO) - A38*1-11 (IMI) Always Below 1 Ω
        E28-6 (EFIO) or A38*1-11 (IMI) - Body ground Always 10 kΩ or higher
        E28-6 (EFIO) - A52*2-11 (IMI) Always Below 1 Ω
        E28-6 (EFIO) or A52*2-11 (IMI) - Body ground Always 10 kΩ or higher

        Tech Tips


        • *1: for LHD

        • *2: for RHD

        Standard Voltage
        Tester Connection Condition Specified Condition
        E28-6 (EFIO) - Body ground Always Below 1 V
        A38*1-11 (IMI) - Body ground
        A52*2-11 (IMI) - Body ground

        Tech Tips


        • *1: for LHD

        • *2: for RHD

      3. for 3UR-FE

        Standard Resistance
        Tester Connection Condition Specified Condition
        E28-6 (EFIO) - A38-40 (IMI) Always Below 1 Ω
        E28-6 (EFIO) or A38-40 (IMI) - Body ground Always 10 kΩ or higher
        Standard Voltage
        Tester Connection Condition Specified Condition
        E28-6 (EFIO) - Body ground Always Below 1 V
        A38-40 (IMI) - Body ground

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  4. CHECK ID CODE BOX (IMMOBILISER CODE ECU) (OUTPUT)

    A01X8X7E02
    *1 Component with harness connected: (ID Code Box (Immobiliser Code ECU))
    *2 LOW

    1. Using an oscilloscope, check the waveform.

      Measurement Condition
      Item Content
      Tester Connection E28-6 (EFIO) - E28-8 (GND)
      Tool Setting 10 V/DIV., 100 msec./DIV.
      Condition Engine switch on (IG)
      OK
      Waveform is output normally (see illustration).
      Result
      Result Proceed to
      NG A
      OK (for 1GR-FE) B
      OK (for 1UR-FE) C
      OK (for 1VD-FTV) D
      OK (for 3UR-FE) E

    B

    REPLACE ECM Click here

    C

    REPLACE ECM Click here

    D

    REPLACE ECM Click here

    E

    REPLACE ECM Click here

    A

  5. CHECK ID CODE BOX (IMMOBILISER CODE ECU) (POWER SOURCE AND BODY GROUND)

    A01X8U9E01
    *1 Component with harness connected: (ID Code Box (Immobiliser Code ECU))

    1. Turn the engine switch on (IG).

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

      Standard Voltage
      Tester Connector Condition Specified Condition
      E28-1 (+B) - E28-8 (GND) Always 11 to 14 V

    OK

    REPLACE ID CODE BOX (IMMOBILISER CODE ECU)

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR