IMMOBILISER SYSTEM, Diagnostic DTC:B279986

DTC Code DTC Name
B279986 Engine Immobiliser System Signal (Some Circuit Quantity, Reported via Serial Data) Invalid

DESCRIPTION

If there is a communication malfunction between the ECM and ID code box (immobiliser code ECU), or when the communication ID codes do not match, the ECM stores this DTC.

DTC No. Detection Item DTC Detection Condition Trouble Area Note
B279986 Engine Immobiliser System Signal (Some Circuit Quantity, Reported via Serial Data) Invalid

Either of the following conditions is met (1 trip detection logic*):


  • A malfunction is detected in the communication or communication lines between the ECM and ID code box (immobiliser code ECU).

  • The communication ID codes of the ECM and ID code box (immobiliser code ECU) do not match.

  • ID code box (immobiliser code ECU)

  • ECM

  • Wire harness or connector

DTC output confirmation operation (Perform either of the following):


  • Start the engine and wait for 10 seconds. If there is a malfunction, the engine will stop (communication begins within 3 seconds of the engine start operation being performed, and DTCs are stored after 6 seconds).

  • Connect the cable to the negative (-) battery terminal, start the engine and wait for 10 seconds (communication begins within 3 seconds of the engine switch being turned on (IG), and DTCs are stored after 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 -
Related Data List and Active Test
DTC No. Data List and Active Test
B279986 -

WIRING DIAGRAM

A01VX7WE05

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 the vehicle type 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 performing repairs, confirm that no DTCs are output by performing "DTC Output Confirmation Operation".

Tech Tips

When DTC B279986 and the certification ECU (smart key ECU assembly) DTC are output simultaneously, first perform troubleshooting for the certification ECU (smart key ECU assembly) DTC.

PROCEDURE


  1. REGISTER ECU COMMUNICATION ID


    1. Register the ECU communication ID code.

      Tech Tips

      Refer to Service Bulletin.

      Result
      Proceed to
      NEXT

    NEXT

  2. CLEAR DTC


    1. Clear the DTCs.


      Powertrain > Engine > Clear DTCs
      Result
      Proceed to
      NEXT

    NEXT

  3. CHECK FOR DTC


    1. Perform "DTC Output Confirmation Operation" procedure.

    2. Check for DTCs.


      Powertrain > Engine > Trouble Codes
      OK
      B279986 is not output.
      Result
      Proceed to
      OK
      NG

    OK

    END (COMMUNICATION ID REGISTRATION WAS DEFECTIVE)

    NG

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


    1. Disconnect the J36 ID code box (immobiliser code ECU) connector.

    2. Disconnect the A46*1 or A37*2 ECM connector.


      • *1: for 8AR-FTS

      • *2: for 2GR-FKS

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

      Standard Resistance
      for 8AR-FTS
      Tester Connection Condition Specified Condition
      J36-4 (EFIO) - A46-28 (IMI) Always Below 1 Ω
      J36-3 (EFII) - A46-45 (IMO) Always Below 1 Ω
      J36-4 (EFIO) or A46-28 (IMI) - Body ground Always 10 kΩ or higher
      J36-3 (EFII) or A46-45 (IMO) - Body ground Always 10 kΩ or higher
      for 2GR-FKS
      Tester Connection Condition Specified Condition
      J36-4 (EFIO) - A37-59 (IMI) Always Below 1 Ω
      J36-3 (EFII) - A37-45 (IMO) Always Below 1 Ω
      J36-4 (EFIO) or A37-59 (IMI) - Body ground Always 10 kΩ or higher
      J36-3 (EFII) or A37-45 (IMO) - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  5. 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

  6. REGISTER RECOGNITION CODE


    1. Register the recognition codes in the ECUs.

      Tech Tips

      Refer to Service Bulletin.

      Result
      Proceed to
      NEXT

    NEXT

  7. REGISTER ECU COMMUNICATION ID


    1. Register the ECU communication ID.

      Tech Tips

      Refer to Service Bulletin.

      Result
      Proceed to
      NEXT

    NEXT

  8. CHECK WHETHER ENGINE STARTS


    1. Check that the engine starts.

      OK
      Engine starts normally.
      Result
      Proceed to
      OK
      NG

    NG

    REPLACE ECM for 8AR-FTS: Click here
    REPLACE ECM for 2GR-FKS: Click here

    OK

  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.


      Powertrain > Engine > Trouble Codes
      OK
      B279986 is not output.
      Result
      Proceed to
      OK
      NG

    OK

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

    NG

    REPLACE ECM for 8AR-FTS: Click here
    REPLACE ECM for 2GR-FKS: Click here