IMMOBILISER SYSTEM, Diagnostic DTC:B2799, B279986

DTC Code DTC Name
B2799 Engine Immobiliser System Malfunction
B279986 Engine Immobiliser System Signal (Some Circuit Quantity, Reported via Serial Data) Invalid

DESCRIPTION

When 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.

Tech Tips


  • DTC B2799 : for 2AR-FE

  • DTC B279986 : for 2GR-FKS

DTC No. Detection Item DTC Detection Condition Trouble Area Note
B2799 Engine Immobiliser System Malfunction

Either condition is met (1 trip detection logic*):


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

  • A matching communication code cannot be verified during communication between the ECM and ID code box (immobiliser code ECU).

  • ID code box (immobiliser code ECU)

  • ECM

  • Wire harness or connector

DTC output confirmation operation (Either condition is met):


  • Within 10 seconds of an engine start operation being performed (with the shift lever in P and the brake pedal depressed, the engine switch is pressed while the key is being carried). If there is a malfunction, the engine stops (communication begins within 3 seconds of the engine start operation being performed, and DTCs are stored after 6 seconds).

  • 10 seconds after the engine switch is turned on (IG) after reconnecting the cable to the negative (-) battery terminal (communication begins within 3 seconds of the engine switch being turned on (IG), and DTCs are stored after 6 seconds).
B279986 Engine Immobiliser System Signal (Some Circuit Quantity, Reported via Serial Data) Invalid

Either condition is met (1 trip detection logic*):


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

  • A matching communication code cannot be verified during communication between the ECM and ID code box (immobiliser code ECU).

  • ID code box (immobiliser code ECU)

  • ECM

  • Wire harness or connector

DTC output confirmation operation (Either condition is met):


  • Within 10 seconds of an engine start operation being performed (with the shift lever in P and the brake pedal depressed, the engine switch is pressed while the key is being carried). If there is a malfunction, the engine stops (communication begins within 3 seconds of the engine start operation being performed, and DTCs are stored after 6 seconds).

  • 10 seconds after the engine switch is turned on (IG) after reconnecting the cable to the negative (-) battery terminal (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

  • B2799*1

  • B279986*2

 -

WIRING DIAGRAM

B006MYBE04

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 B2799*1 or B279986*2 and the 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. REGISTER ECU COMMUNICATION ID


    1. Register the ECU communication ID.

      Tech Tips

      Refer to Service Bulletin.

      Result
      Proceed to
      NEXT

    NEXT

  2. 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

  3. 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
      B2799*1 or B279986*2 is not output.

      • *1: for 2AR-FE

      • *2: for 2GR-FKS

      Result
      Result Proceed to
      B2799 is not output (for 2AR-FE) A
      B279986 is not output (for 2GR-FKS)
      B279986 is output (for 2GR-FKS) B
      B2799 is output (for 2AR-FE) C

    A

    END (COMMUNICATION ID REGISTRATION WAS DEFECTIVE)

    C

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

    B

  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
      G15-3 (EFII) - A53-45 (IMO) Always Below 1 Ω
      G15-4 (EFIO) or A53-59 (IMI) - Body ground Always 10 kΩ or higher
      G15-3 (EFII) or A53-45 (IMO) - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  5. REPLACE ECM


    1. Temporarily replace the ECM with a new one.

      Click here

      Result
      Proceed to
      NEXT

    NEXT

  6. CLEAR DTC


    1. Clear the DTCs.


      Powertrain > Engine > Clear DTCs
      Result
      Proceed to
      NEXT

    NEXT

  7. CHECK FOR DTC


    1. Perform "DTC Output Confirmation Operation" procedure.

    2. Check for DTCs.


      Powertrain > Engine > Trouble Codes
      OK
      B2799 is not output.
      Result
      Proceed to
      OK
      NG

    OK

    END (ECM WAS DEFECTIVE)

    NG

    REPLACE ID CODE BOX (IMMOBILISER CODE ECU)

  8. 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
      G15-3 (EFII) - A53-45 (IMO) Always Below 1 Ω
      G15-4 (EFIO) or A53-28 (IMI) - Body ground Always 10 kΩ or higher
      G15-3 (EFII) or A53-45 (IMO) - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  9. REPLACE ECM


    1. Temporarily replace the ECM with a new one.

      Click here

      Result
      Proceed to
      NEXT

    NEXT

  10. CLEAR DTC


    1. Clear the DTCs.


      Powertrain > Engine and ECT > Clear DTCs
      Result
      Proceed to
      NEXT

    NEXT

  11. CHECK FOR DTC


    1. Perform "DTC Output Confirmation Operation" procedure.

    2. Check for DTCs.


      Powertrain > Engine and ECT > Trouble Codes
      OK
      B2799 is not output.
      Result
      Proceed to
      OK
      NG

    OK

    END (ECM WAS DEFECTIVE)

    NG

    REPLACE ID CODE BOX (IMMOBILISER CODE ECU)