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 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 the ID code box (immobiliser code ECU) is stuck on HI output.

  • Harness or connector

  • ID code box (immobiliser code ECU)

  • ECM

WIRING DIAGRAM

A00KUCGE04

INSPECTION PROCEDURE

Note


  • When replacing the ID code box (immobiliser code ECU) or ECM, refer to the Service Bulletin.

  • Inspect the fuses for circuits related to this system before performing the following inspection procedure.

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
      No DTC is not output A
      DTC B279A and other DTCs are output B
      DTC B279A is output C

    B

    Go to DIAGNOSTIC TROUBLE CODE CHART Click here

    C

    CHECK HARNESS AND CONNECTOR (ID CODE BOX - ECM) Click here

    A

    USE SIMULATION METHOD TO CHECK Click here

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


    1. Disconnect the G37 ID code box (immobiliser code ECU) connector.

    2. Disconnect the G56*1 or G58*2 ECM connector.


      • *1: for 1GR-FE

      • *2: for 1KD-FTV

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

      Standard Resistance
      for 1GR-FE
      Tester Connection Condition Specified Condition
      G37-6 (EFIO) - G56-14 (IMI) Always Below 1 Ω
      G37-6 (EFIO) or G56-14 (IMI) - Body ground Always 10 kΩ or higher
      for 1KD-FTV
      Tester Connection Condition Specified Condition
      G37-6 (EFIO) - G58-28 (IMI) Always Below 1 Ω
      G37-6 (EFIO) or G58-28 (IMI) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

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


    1. Using an oscilloscope, check the waveform.

      A00KUF1E02
      Text in Illustration
      *A for 1GR-FE *B for 1KD-FTV
      *a

      Component with harness connected

      (ECM)

      		 - -
      Measurement Condition
      Item Content
      Tester Connection

      G56-14 (IMI) - Body ground*1

      G58-28 (IMI) - Body ground*2
      Tool Setting 10 V/DIV., 100 ms./DIV.
      Condition Engine switch on (IG)

      • *1: for 1GR-FE

      • *2: for 1KD-FTV

      OK
      Waveform is output normally (refer to illustration).
      Result
      Result Proceed to
      NG A
      OK (for 1GR-FE) B
      OK (for 1KD-FTV) C

    B

    REPLACE ECM Click here

    C

    REPLACE ECM Click here

    A

  5. CHECK HARNESS AND CONNECTOR (ID CODE BOX - BATTERY AND BODY GROUND)


    1. A00KWA0E04
      Text in Illustration
      *a

      Front view of wire harness connector

      (to ID Code Box [Immobiliser Code ECU])

      Disconnect the G37 ID code box (immobiliser code ECU) connector.

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      G37-1 (+B) - Body ground Always 11 to 14 V

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      G37-8 (GND) - Body ground Always Below 1 Ω

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  6. REPLACE ECM


    1. Temporarily replace the ECM with a new one.



    NEXT

  7. REGISTER ECU COMMUNICATION ID


    1. Register the ECU communication ID (Refer to the Service Bulletin).


    NEXT

  8. CLEAR DTC


    1. Clear the DTCs Click here.


    NEXT

  9. CHECK FOR DTC


    1. Check for DTCs Click here.

      OK
      DTC B279A is not output.

    NG

    REPLACE ID CODE BOX (IMMOBILISER CODE ECU)

    OK

    END (ECM IS DEFECTIVE)