IMMOBILISER SYSTEM(w/o Entry and Start System), Diagnostic DTC:B279A and B279A12

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

DESCRIPTION

If the communication line (EFIO-IMI) to the transponder key ECU assembly is stuck high (e.g. shorted to +B), the ECM stores this DTC.

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

Note

B279A

Theft Deterrent System Communication Line High Fixation

Communication line (EFIO-IMI) between the ECM and transponder key ECU assembly is stuck high.

  • Wire harness or connector

  • ECM

  • Transponder key ECU assembly

  • DTC Output Confirmation Operation:

  • Turn the ignition switch to ON and wait 6 seconds.

B279A12

Engine Immobiliser System Circuit Short to Battery

Communication line (EFIO-IMI) between the ECM and transponder key ECU assembly is stuck high.

  • Wire harness or connector

  • ECM

  • Transponder key ECU assembly

  • DTC Output Confirmation Operation:

  • Turn the ignition switch to ON and wait 6 seconds.
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 (initial ignition occurs and engine cranks, then ignition stops)

Engine cannot be started
Table 2. Related Data List and Active Test

DTC No.

Data List and Active Test

  • B279A*1

  • B279A12*2

-

  • *1: except 8NR-FTS

  • *2: for 8NR-FTS

WIRING DIAGRAM

B520146E02

CAUTION / NOTICE / HINT

Note:

  • If the transponder key ECU assembly or ECM is replaced, refer to Service Bulletin.

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

PROCEDURE

  1. CLEAR DTC

    1. Clear the DTCs.

      Powertrain > Engine and ECT > Clear DTCs

      Powertrain > Engine > Clear DTCs

    Result

    Proceed to

    NEXT
    NEXT

  2. CHECK FOR DTC

    1. Check for DTCs.

      Powertrain > Engine and ECT > Trouble Codes

      Powertrain > Engine > Trouble Codes

      Tip:

      Before checking for DTCs, perform the "DTC Output Confirmation Operation" procedure.

      OK

      DTC B279A*1 or B279A12*2 is not output.

    Result

    Result

    Proceed to

    B279A*1 or B279A12*2 is not output

    A

    B279A*1 or B279A12*2 is output

    B

    • *1: except 8NR-FTS

    • *2: for 8NR-FTS

    A

    USE SIMULATION METHOD TO CHECK

    Click here

    B

  3. CHECK CONNECTION OF CONNECTOR

    1. Check that the connectors are properly connected to the ECM and transponder key ECU assembly.

      OK

      Connectors are properly connected.

    Result

    Proceed to

    OK

    NG
    NG

    CONNECT CONNECTORS PROPERLY

    OK

  4. CHECK HARNESS AND CONNECTOR (TRANSPONDER KEY ECU ASSEMBLY - ECM AND BODY GROUND)

    1. for 1ZR-FE, 2ZR-FE, 1ZR-FAE or 1NR-FE

      1. Disconnect the E21 transponder key ECU assembly connector.

      2. Disconnect the A50 ECM connector.

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

        Standard Resistance

        Tester Connection

        Condition

        Specified Condition

        E21-13 (EFIO) - A50-28 (IMI)

        Always

        Below 1 Ω

        E21-13 (EFIO) - Body ground

        Always

        10 kΩ or higher

        A50-28 (IMI) - Body ground

        Always

        10 kΩ or higher

    2. for 1ND-TV

      1. Disconnect the E21 transponder key ECU assembly connector.

      2. Disconnect the A101 ECM connector.

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

        Standard Resistance

        Tester Connection

        Condition

        Specified Condition

        E21-13 (EFIO) - A101-77 (IMI)

        Always

        Below 1 Ω

        E21-13 (EFIO) - Body ground

        Always

        10 kΩ or higher

        A101-77 (IMI) - Body ground

        Always

        10 kΩ or higher

    3. for 8NR-FTS

      1. Disconnect the E21 transponder key ECU assembly connector.

      2. Disconnect the A173 ECM connector.

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

        Standard Resistance

        Tester Connection

        Condition

        Specified Condition

        E21-13 (EFIO) - A173-28 (IMI)

        Always

        Below 1 Ω

        E21-13 (EFIO) - Body ground

        Always

        10 kΩ or higher

        A173-28 (IMI) - Body ground

        Always

        10 kΩ or higher

    Result

    Proceed to

    OK

    NG
    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  5. REPLACE TRANSPONDER KEY ECU ASSEMBLY

    1. Replace the transponder key ECU assembly with a new one.

    Result

    Proceed to

    NEXT
    NEXT

  6. CLEAR DTC

    1. Clear the DTCs.

      Powertrain > Engine and ECT > Clear DTCs

    Result

    Proceed to

    NEXT
    NEXT

  7. CHECK FOR DTC

    1. Check for DTCs.

      Tip:

      Before checking for DTCs, perform the "DTC Output Confirmation Operation" procedure.

      OK

      DTC B279A*1 or B279A12*2 is not output.

    Result

    Result

    Proceed to

    B279A is not output

    A

    B279A*1 or B279A12*2 is output

    B

    • *1: except 8NR-FTS

    • *2: for 8NR-FTS

    A

    END (TRANSPONDER KEY ECU ASSEMBLY WAS DEFECTIVE)

    B

    REPLACE ECM

    for 1ND-TV:Click here

    for 1NR-FE:Click here

    for 1ZR-FAE:Click here

    for 1ZR-FE:Click here

    for 2ZR-FE:Click here

    for 8NR-FTS:Click here