IMMOBILISER SYSTEM, Diagnostic DTC:B279A, B279A12

DTC Code DTC Name
B279A Theft Deterrent System Communication Line High Fixation
B279A12 Engine Immobiliser System Circuit Short to Battery

DESCRIPTION

When the communication line (IMI - EFIO) between the ECM and ID code box (immobiliser code ECU) is stuck high, the ECM stores this DTC.

Tech Tips


  • DTC B279A : for 2AR-FE

  • DTC B279A12 : for 2GR-FKS

DTC No. Detection Item DTC Detection Condition Trouble Area Note
B279A Theft Deterrent System Communication Line High Fixation The communication line (IMI - EFIO) between the ECM and ID code box (immobiliser code ECU) is stuck high. (1 trip detection logic*)

  • ID code box (immobiliser code ECU)

  • ECM

  • Wire harness or connector

DTC output confirmation operation:


  • Turn the engine switch on (IG) and wait 6 seconds.
B279A12 Engine Immobiliser System Circuit Short to Battery The communication line (IMI - EFIO) between the ECM and ID code box (immobiliser code ECU) is stuck high. (1 trip detection logic*)

  • ID code box (immobiliser code ECU)

  • ECM

  • Wire harness or connector

DTC output confirmation operation:


  • Turn the engine switch on (IG) and wait 6 seconds.

Vehicle Condition and Fail-safe Operation when Malfunction Detected
Vehicle Condition when Malfunction Detected Fail-safe Operation when Malfunction Detected
Engine cannot be started Engine cannot be started
Related Data List and Active Test
DTC No. Data List and Active Test

  • B279A*1

  • B279A12*2

 -

WIRING DIAGRAM

B006LFME04

CAUTION / NOTICE / HINT

Note


  • When using the GTS with the engine switch off, connect the GTS to the DLC3 and turn a courtesy light switch on and off at intervals of 1.5 seconds or less until communication between the GTS and the vehicle begins. Then select Model Code "KEY REGIST" under manual mode and enter the following menus: Body Electrical / Entry&Start(CAN). While using the GTS, periodically turn a courtesy light switch on and off at intervals of 1.5 seconds or less to maintain communication between the GTS and the vehicle.

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

  • After repair, confirm that no DTCs are output by performing "DTC Output Confirmation Operation."

Tech Tips

When DTC B279A*1 or B279A12*2 and a certification ECU (smart key ECU assembly) DTC are output simultaneously, first perform troubleshooting for the certification ECU (smart key ECU assembly) DTC.


  • *1: for 2AR-FE

  • *2: for 2GR-FKS

PROCEDURE


  1. CLEAR DTC


    1. Clear the DTCs.


      1. for 2AR-FE


        Powertrain > Engine and ECT > Clear DTCs

      2. for 2GR-FKS


        Powertrain > Engine > Clear DTCs
      Result
      Proceed to
      NEXT

    NEXT

  2. CHECK FOR DTC


    1. Turn the engine switch on (IG) and wait 10 seconds.

    2. Check for DTCs.


      1. for 2AR-FE


        Powertrain > Engine and ECT > Trouble Codes

      2. for 2GR-FKS


        Powertrain > Engine > Trouble Codes

        Tech Tips

        If DTCs other than DTC B279A*1 or B279A12*2 are output, troubleshoot those DTCs first.


        • *1: for 2AR-FE

        • *2: for 2GR-FKS

      Result
      Result Proceed to
      DTC B279A is output (for 2AR-FE) A
      DTC B279A12 is output (for 2GR-FKS)
      DTC B279A and other DTCs are output (for 2AR-FE) B
      DTC B279A12 and other DTCs are output (for 2GR-FKS)

    B

    GO TO DIAGNOSTIC TROUBLE CODE CHART Click here

    A

  3. CHECK CONNECTION OF CONNECTOR


    1. Turn the engine switch off.

    2. Check that the connectors are properly connected to the ECM and ID code box (immobiliser code ECU).

      OK
      Connectors are properly connected.
      Result
      Result Proceed to
      OK (for 2GR-FKS) A
      OK (for 2AR-FE) B
      NG C

    B

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

    C

    CONNECT CONNECTORS PROPERLY

    A

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


    1. Disconnect the G15 ID code box (immobiliser code ECU) connector.

    2. Disconnect the A53 ECM connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      G15-4 (EFIO) - A53-59 (IMI) Always Below 1 Ω
      G15-4 (EFIO) or A53-59 (IMI) - Body ground Always 10 kΩ or higher

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      A53-59 (IMI) - Body ground Always Below 1 V
      Result
      Proceed to
      OK
      NG

    OK

    GO TO STEP 6 Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

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


    1. Disconnect the G15 ID code box (immobiliser code ECU) connector.

    2. Disconnect the A53 ECM connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      G15-4 (EFIO) - A53-28 (IMI) Always Below 1 Ω
      G15-4 (EFIO) or A53-28 (IMI) - Body ground Always 10 kΩ or higher

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      A53-28 (IMI) - Body ground Always Below 1 V
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  6. REPLACE ID CODE BOX (IMMOBILISER CODE ECU)


    1. Replace the ID code box (immobiliser code ECU) with a new one.

      Tech Tips

      Refer to Service Bulletin.

      Result
      Proceed to
      NEXT

    NEXT

  7. REGISTER RECOGNITION CODE


    1. Register the recognition codes in the ECUs.

      Tech Tips

      Refer to Service Bulletin.

      Result
      Proceed to
      NEXT

    NEXT

  8. REGISTER ECU COMMUNICATION ID


    1. Register the ECU communication ID.

      Tech Tips

      Refer to Service Bulletin.

      Result
      Proceed to
      NEXT

    NEXT

  9. CLEAR DTC


    1. Clear the DTCs.


      Powertrain > Engine > Clear DTCs
      Result
      Proceed to
      NEXT

    NEXT

  10. CHECK FOR DTC


    1. Perform "DTC Output Confirmation Operation" procedure.

    2. Check for DTCs.


      1. for 2AR-FE


        Powertrain > Engine and ECT > Trouble Codes

      2. for 2GR-FKS


        Powertrain > Engine > Trouble Codes
      OK
      DTC B279A*1 or B279A12*2 is not output.

      • *1: for 2AR-FE

      • *2: for 2GR-FKS

      Result
      Result Proceed to
      B279A is not output A
      B279A12 is output (for 2GR-FKS) B
      B279A is output (for 2AR-FE) C

    A

    END (ID CODE BOX (IMMOBILISER CODE ECU) WAS DEFECTIVE)

    B

    REPLACE ECM Click here

    C

    REPLACE ECM Click here