ENGINE IMMOBILISER SYSTEM (w/ Smart Entry and Start 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


DTC Code DTC Detection Condition Trouble Area DTC Output Confirmation Operation
B2799

Either condition is met (1 trip detection logic*3):


  • A malfunction in the communication or communication lines between the ECM and ID code box (immobiliser code ECU)*1 or certification ECU (smart key ECU assembly)*2.

  • A matching communication code cannot be verified during communication between the ECM and ID code box (immobiliser code ECU)*1 or certification ECU (smart key ECU assembly)*2.

  • ID code box (immobiliser code ECU)*1

  • Certification ECU (smart key ECU assembly)*2

  • ECM

  • Wire 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*1

  • B279986*2

 -

WIRING DIAGRAM

B000M2QE05

INSPECTION PROCEDURE

Note


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

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


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.


PROCEDURE


  1. REGISTER ECU COMMUNICATION ID


    1. Register the ECU communication ID.

      Tech Tips

      Refer to Service Bulletin.


    NEXT

  2. CLEAR DTC


    1. Clear the DTCs Click here.


    NEXT

  3. CHECK FOR DTC


    1. Start the engine.

    2. Perform "DTC Output Confirmation Operation" procedure.

    3. Check for DTCs Click here.

      OK
      DTC B2799*1 or B279986*2 is not output.
      Result
      Result Proceed to
      OK A
      NG (DTC B2799*1 or B279986*2 is output) (w/o Entry Function on Driver Door or for TMMK Made) B
      NG (DTC B2799 is output) (w/ Entry Function on Driver Door except TMMK Made) C
      NG (Other DTCs are output) D

      • *1: for 2AR-FE

      • *2: for 6AR-FSE


    B

    CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - ECM) Click here

    C

    REGISTER ECU COMMUNICATION ID Click here

    D

    GO TO DIAGNOSTIC TROUBLE CODE CHART Click here

    A

    END (COMMUNICATION ID REGISTRATION WAS DEFECTIVE)

  4. CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - ECM)


    1. Disconnect the A43 certification ECU (smart key ECU assembly) connector.

    2. Disconnect the A25*1 or A84*2 ECM connector.


      • *1: for 2AR-FE

      • *2: for 6AR-FSE

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

      Standard Resistance
      for 2AR-FE
      Tester Connection Condition Specified Condition
      A43-14 (EFII) - A25-29 (IMO) Always Below 1 Ω
      A43-14 (EFII) or A25-29 (IMO) - Body ground Always 10 kΩ or higher
      A43-13 (EFIO) - A25-28 (IMI) Always Below 1 Ω
      A43-13 (EFIO) or A25-28 (IMI) - Body ground Always 10 kΩ or higher
      for 6AR-FE
      Tester Connection Condition Specified Condition
      A43-14 (EFII) - A84-45 (IMO) Always Below 1 Ω
      A43-14 (EFII) or A84-45 (IMO) - Body ground Always 10 kΩ or higher
      A43-13 (EFIO) - A84-28 (IMI) Always Below 1 Ω
      A43-13 (EFIO) or A84-28 (IMI) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  5. INSPECT CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) (TERMINAL EFII)


    1. Using an oscilloscope, check the waveform.

      B000LX4E01
      Text in Illustration
      *a

      Component with harness connected

      (Certification ECU (Smart Key ECU Assembly))

      		 *b Approximately 160 ms
      *c Approximately 270 ms *d Waveform
      Measurement Condition
      Tester Connection Condition Tool Setting Specified Condition
      A43-14 (EFII) - Body ground Within 3 seconds of engine start or within 3 seconds of engine switch turned on (IG) after battery cable disconnected and reconnected 2 V/DIV., 500 ms./DIV.

      Pulse generation

      (See waveform)
      OK
      The waveform is similar to that shown in the illustration.
      Result
      Result Proceed to
      Normal waveform A
      Terminal IMO stuck low (2.4 V or less) B
      Terminal IMO stuck high (12 V), or has abnormal wavelength or shape (for 2AR-FE) C
      Terminal IMO stuck high (12 V), or has abnormal wavelength or shape (for 6AR-FSE) D

    B

    INSPECT ECM (IMO TERMINAL VOLTAGE) Click here

    C

    REPLACE ECM Click here

    D

    REPLACE ECM Click here

    A

  6. INSPECT CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) (TERMINAL EFIO)


    1. Using an oscilloscope, check the waveform.

      B000HN2E01
      Text in Illustration
      *a

      Component with harness connected

      (Certification ECU (Smart Key ECU Assembly))

      		 *b Approximately 160 ms
      *c Approximately 270 ms *d Waveform
      Measurement Condition
      Tester Connection Condition Tool Setting Specified Condition
      A43-13 (EFIO) - Body ground Engine switch on (IG) using registered electrical key transmitter sub-assembly 2 V/DIV., 500 ms./DIV.

      Pulse generation

      (See waveform)
      OK
      The waveform is similar to that shown in the illustration.

    NG

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

    OK

  7. REGISTER ECU COMMUNICATION ID


    1. Register the ECU communication ID.

      Tech Tips

      Refer to Service Bulletin.


    NEXT

  8. CHECK WHETHER ENGINE STARTS


    1. Using an electrical key transmitter sub-assembly which is registered to the vehicle, turn the engine switch on (IG).

    2. Check that the engine starts 5 seconds after the engine switch was turned on (IG).

      OK
      Engine starts normally.
      Result
      Result Proceed to
      OK A
      NG (for 2AR-FE) B
      NG (for 6AR-FSE) C

    B

    REPLACE ECM Click here

    C

    REPLACE ECM Click here

    A

    END (COMMUNICATION ID REGISTRATION WAS DEFECTIVE)

  9. INSPECT ECM (IMO TERMINAL VOLTAGE)


    1. B000NMNE78
      Text in Illustration
      *A for 2AR-FE
      *B for 6AR-FSE
      *a

      Front view of wire harness connector

      (to ECM)

      Disconnect the A25*1 or A84*2 ECM connector.


      • *1: for 2AR-FE

      • *2: for 6AR-FSE

    2. Turn the engine switch on (IG).

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

      Standard Voltage
      for 2AR-FE
      Tester Connection Condition Specified Condition
      A25-29 (IMO) - Body ground Engine switch on (IG) using registered electrical key transmitter sub-assembly Terminal IMO stuck low (2.4 V or less)
      Terminal IMO stuck high (12 V) or abnormal waveform
      for 6AR-FSE
      Tester Connection Condition Specified Condition
      A84-45 (IMO) - Body ground Engine switch on (IG) using registered electrical key transmitter sub-assembly Terminal IMO stuck low (2.4 V or less)
      Terminal IMO stuck high (12 V) or abnormal waveform
      Result
      Result Proceed to
      Terminal IMO stuck low (2.4 V or less) A
      Terminal IMO stuck high (12 V) or abnormal waveform (for 2AR-FE) B
      Terminal IMO stuck high (12 V) or abnormal waveform (for 6AR-FSE) C

    B

    REPLACE ECM Click here

    C

    REPLACE ECM Click here

    A

  10. REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)


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

      Tech Tips

      Refer to Service Bulletin.


    NEXT

  11. REGISTER ECU COMMUNICATION ID


    1. Register the ECU communication ID.

      Tech Tips

      Refer to Service Bulletin.


    NEXT

  12. CHECK WHETHER ENGINE STARTS


    1. Using an electrical key transmitter sub-assembly which is registered to the vehicle, turn the engine switch on (IG).

    2. Check that the engine starts 5 seconds after the engine switch was turned on (IG).

      OK
      Engine starts normally.
      Result
      Result Proceed to
      OK A
      NG (for 2AR-FE) B
      NG (for 6AR-FSE) C

    B

    REPLACE ECM Click here

    C

    REPLACE ECM Click here

    A

    END (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) WAS DEFECTIVE)

  13. REGISTER ECU COMMUNICATION ID

    Register the ECU communication ID.

    Tech Tips

    Refer to Service Bulletin.


    NEXT

  14. CLEAR DTC


    1. Clear the DTCs Click here.


    NEXT

  15. CHECK FOR DTC


    1. Perform "DTC Output Confirmation Operation" procedure.

    2. Check for DTCs Click here.

      OK
      DTC B2799 is not output.

    NG

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

    OK

    END (COMMUNICATION ID REGISTRATION WAS DEFECTIVE)

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


    1. Disconnect the I20 ID code box (immobiliser code ECU) connector.

    2. Disconnect the A25 ECM connector.

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

      Standard Resistance
      for 2GR-FE
      Tester Connection Condition Specified Condition
      I20-3 (EFII) - A25-30 (IMO) Always Below 1 Ω
      I20-3 (EFII) or A25-30 (IMO) - Body ground Always 10 kΩ or higher
      I20-4 (EFIO) - A25-31 (IMI) Always Below 1 Ω
      I20-4 (EFIO) or A25-31 (IMI) - Body ground Always 10 kΩ or higher
      for 2AR-FE
      Tester Connection Condition Specified Condition
      I20-3 (EFII) - A25-29 (IMO) Always Below 1 Ω
      I20-3 (EFII) or A25-29 (IMO) - Body ground Always 10 kΩ or higher
      I20-4 (EFIO) - A25-28 (IMI) Always Below 1 Ω
      I20-4 (EFIO) or A25-28 (IMI) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  17. REPLACE ECM


    1. Temporarily replace the ECM with a new one Click here for 2GR-FE , Click here for 2AR-FE).


    NEXT

  18. CLEAR DTC


    1. Clear the DTCs Click here.


    NEXT

  19. CHECK FOR DTC


    1. Perform "DTC Output Confirmation Operation" procedure.

    2. Check for DTCs Click here.

      OK
      DTC B2799 is not output.

    NG

    REPLACE ID CODE BOX (IMMOBILISER CODE ECU)

    OK

    END (ECM WAS DEFECTIVE)