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

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

DESCRIPTION

When the communication line (IMI - EFIO) between the ECM and certification ECU (smart key ECU assembly)*2 or ID code box (immobiliser code ECU)*3 is stuck high, the ECM stores this DTC.

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 certification ECU (smart key ECU assembly)*2 or ID code box (immobiliser code ECU)*3 is stuck high. (1 trip detection logic*1)

  • Certification ECU (smart key ECU assembly)*2

  • ID code box (immobiliser code ECU)*3

  • ECM

  • Wire harness or connector

DTC output confirmation operation:

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

  • *1: Only output while a malfunction is present.

  • *2: for LHD

  • *3: for RHD

Table 1. 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
Table 2. Related Data List and Active Test

DTC No.

Data List and Active Test

B279A

-

WIRING DIAGRAM

  1. for LHD

    B388975E01

  2. for RHD

    B388976E01

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, certification ECU (smart key ECU assembly)*1 or ID code box (immobiliser code ECU)*2, refer to Service Bulletin.

    • *1: for LHD

    • *2: for RHD

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

Tip:

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

PROCEDURE

  1. CLEAR DTC

    1. Clear the DTCs.

      1. for 1KR-FE

        Powertrain > Engine and ECT > Clear DTCs

      2. for 1PP

        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 1KR-FE

        Powertrain > Engine and ECT > Trouble Codes

      2. for 1PP

        Powertrain > Engine > Trouble Codes

    Tip:

    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 CONNECTION OF CONNECTOR

    1. Turn the engine switch off.

    2. Check that the connectors are properly connected to the ECM and certification ECU (smart key ECU assembly)*1 or ID code box (immobiliser code ECU)*2.

      • *1: for LHD

      • *2: for RHD

      OK

      Connectors are properly connected.

    Result

    Result

    Proceed to

    OK (for LHD)

    A

    OK (for RHD)

    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 (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - ECM)

    1. Disconnect the E50 certification ECU (smart key ECU assembly) connector.

    2. Disconnect the A34*1 or B56*2 ECM connector.

      • *1: for 1KR-FE

      • *2: for 1PP

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

      Standard Resistance

      Tester Connection

      Condition

      Specified Condition

      E50-35 (EFIO) - A34-42 (IMI)*1

      Always

      Below 1 Ω

      E50-35 (EFIO) - B56-19 (IMI)*2

      Always

      Below 1 Ω

      E50-35 (EFIO) or A34-42 (IMI) - Body ground*1

      Always

      10 kΩ or higher

      E50-35 (EFIO) or B56-19 (IMI) - Body ground*2

      Always

      10 kΩ or higher

      • *1: for 1KR-FE

      • *2: for 1PP

    Result

    Proceed to

    OK

    NG
    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  5. REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

    1. Replace the certification ECU (smart key ECU assembly) with a new one.

      Tip:

      Refer to Service Bulletin.

    Result

    Proceed to

    NEXT
    NEXT

  6. REGISTER ECU COMMUNICATION ID

    1. Register the ECU communication ID.

      Tip:

      Refer to Service Bulletin.

    Result

    Proceed to

    NEXT
    NEXT

  7. CLEAR DTC

    1. Clear the DTCs.

      1. for 1KR-FE

        Powertrain > Engine and ECT > Clear DTCs

      2. for 1PP

        Powertrain > Engine > Clear DTCs

    Result

    Proceed to

    NEXT
    NEXT

  8. CHECK FOR DTC

    1. Perform "DTC Output Confirmation Operation" procedure.

    2. Check for DTCs.

      1. for 1KR-FE

        Powertrain > Engine and ECT > Trouble Codes

      2. for 1PP

        Powertrain > Engine > Trouble Codes

    OK

    DTC B279A is not output.

    Result

    Proceed to

    OK

    NG
    OK

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

    NG

    REPLACE ECM

    for 1KR-FE:Click here

    for 1PP:Click here

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

    1. Disconnect the E48 ID code box (immobiliser code ECU) connector.

    2. Disconnect the A34*1 or B56*2 ECM connector.

      • *1: for 1KR-FE

      • *2: for 1PP

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

      Standard Resistance

      Tester Connection

      Condition

      Specified Condition

      E48-4 (EFIO) - A34-42 (IMI)*1

      Always

      Below 1 Ω

      E48-4 (EFIO) - B56-19 (IMI)*2

      Always

      Below 1 Ω

      E48-4 (EFIO) or A34-42 (IMI) - Body ground*1

      Always

      10 kΩ or higher

      E48-4 (EFIO) or B56-19 (IMI) - Body ground*2

      Always

      10 kΩ or higher

      • *1: for 1KR-FE

      • *2: for 1PP

    Result

    Proceed to

    OK

    NG
    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  10. REPLACE ID CODE BOX (IMMOBILISER CODE ECU)

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

      Tip:

      Refer to Service Bulletin.

    Result

    Proceed to

    NEXT
    NEXT

  11. REGISTER RECOGNITION CODE

    1. Register the recognition codes in the ECUs.

      Tip:

      Refer to Service Bulletin.

    Result

    Proceed to

    NEXT
    NEXT

  12. REGISTER ECU COMMUNICATION ID

    1. Register the ECU communication ID.

      Tip:

      Refer to Service Bulletin.

    Result

    Proceed to

    NEXT
    NEXT

  13. CLEAR DTC

    1. Clear the DTCs.

      1. for 1KR-FE

        Powertrain > Engine and ECT > Clear DTCs

      2. for 1PP

        Powertrain > Engine > Clear DTCs

    Result

    Proceed to

    NEXT
    NEXT

  14. CHECK FOR DTC

    1. Perform "DTC Output Confirmation Operation" procedure.

    2. Check for DTCs.

      1. for 1KR-FE

        Powertrain > Engine and ECT > Trouble Codes

      2. for 1PP

        Powertrain > Engine > Trouble Codes

    OK

    DTC B279A is not output.

    Result

    Proceed to

    OK

    NG
    OK

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

    NG

    REPLACE ECM

    for 1KR-FE:Click here

    for 1PP:Click here