ENGINE IMMOBILISER SYSTEM (w/ Smart Entry and Start System), Diagnostic DTC:B2799

DTC Code DTC Name
B2799 Engine Immobiliser System Malfunction

DESCRIPTION

When there are communication malfunctions 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 Code DTC Detection Condition Trouble Area DTC Output Confirmation Operation
B2799

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

  • Harness or connector

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 carrying the key). 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 Code Data List and Active Test
B2799 -

WIRING DIAGRAM

A003FTAE37

INSPECTION PROCEDURE

Note


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

  • After performing repairs, perform the DTC output confirmation operation, and then confirm that no DTCs are output again.

Tech Tips

When DTC B2799 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. REGISTER ECU COMMUNICATION ID


    1. Register the ECU communication ID.

      Tech Tips

      Refer to the Service Bulletin.


    NEXT

  2. CLEAR DTC


    1. Clear the DTCs Click here.


    NEXT

  3. CHECK FOR DTC


    1. Check for DTCs Click here.

      Tech Tips

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

      OK
      DTC B2799 is not output.

    NG

    REPLACE ECM Click here

    OK

    END (ECU COMMUNICATION ID HAS NOT BEEN REGISTERED)

  4. REPLACE ECM


    1. Temporarily replace the ECM with a new or known good one Click here.


    NEXT

  5. CLEAR DTC


    1. Clear the DTCs Click here.


    NEXT

  6. CHECK FOR DTC


    1. Check for DTCs Click here.

      Tech Tips

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

      OK
      DTC B2799 is not output.

    NG

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

    OK

    END (ECM WAS DEFECTIVE)

  7. CHECK HARNESS AND CONNECTOR (ID CODE BOX [IMMOBILISER CODE ECU] - ECM)


    1. Disconnect the H81 ID code box (immobiliser code ECU) connector.

    2. Disconnect the B72 ECM connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      H81-3 (EFII) - B72-15 (IMO) Always Below 1 Ω
      H81-3 (EFII) - Body ground Always 10 kΩ or higher
      B72-15 (IMO) - Body ground Always 10 kΩ or higher
      H81-4 (EFIO) - B72-16 (IMI) Always Below 1 Ω
      H81-4 (EFIO) - Body ground Always 10 kΩ or higher
      B72-16 (IMI) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

    REPLACE ID CODE BOX (IMMOBILISER CODE ECU)