ENGINE IMMOBILISER SYSTEM(w/o 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 transponder key ECU is stuck on HI output, the ECM stores this DTC.

DTC Code DTC Detection Condition Trouble Area
B279A The communication line (EFIO-IMI) between the ECM and transponder key ECU is stuck on HI output for 6 seconds or more

  • Harness or connector

  • Transponder key ECU

  • ECM

WIRING DIAGRAM

A004O7HE05
*a from ECU-B2 Fuse
*b Transponder Key ECU

CAUTION / NOTICE / HINT

Tech Tips

When the transponder key ECU and/or ECM is replaced, reregister the ECU - ECM communication ID.

PROCEDURE


  1. CLEAR DTC


    1. Clear the DTC Click here.


    NEXT

  2. CHECK FOR DTC


    1. Check for DTC Click here.

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

      Tech Tips

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


    B

    GO TO DIAGNOSTIC TROUBLE CODE CHART Click here

    A

  3. CHECK HARNESS AND CONNECTOR (TRANSPONDER KEY ECU - ECM)


    1. Disconnect the D102 transponder key ECU connector.

    2. Disconnect the A83 ECM connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      D102-13 (EFIO) - A83-34 (IMI) Always Below 1 Ω
      D102-13 (EFIO) or A83-34 (IMI) - Body ground Always 10 kΩ or higher
      Standard Voltage
      Tester Connection Condition Specified Condition
      D102-13 (EFIO) - Body ground Always Below 1 V
      A83-34 (IMI) - Body ground

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  4. CHECK TRANSPONDER KEY ECU (OUTPUT)


    1. A004Q2EE02
      *1 Component with harness connected: (Transponder Key ECU)
      *2 Normal Waveform
      *3 LOW

      Measure the waveform.

      Waveform 1 (Reference)
      Terminal No. (Symbols) Tool Setting Switch Condition
      D102-13 (EFIO) - D102-16 (GND) 10 V/DIV., 500 msec./DIV. Ignition switch ON
      OK
      Waveform is output normally (see illustration).
      Result
      Result Proceed to
      OK (for 1WW) A
      OK (for 2WW) B
      NG C

    A

    REPLACE ECM Click here

    B

    REPLACE ECM Click here

    C

  5. CHECK TRANSPONDER KEY ECU (POWER SOURCE AND BODY GROUND)

    A004OTQE02
    Text in Illustration
    *1

    Component with harness connected

    (Transponder Key ECU)

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      D102-1 (+B) - D102-16 (GND) Always 11 to 14 V

    OK

    REPLACE TRANSPONDER KEY ECU

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR