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

DTC Code DTC Name
B2799 Engine Immobiliser System Malfunction

DESCRIPTION

The ECM stores this DTC when a communication line between the ECM and transponder key ECU assembly is malfunctioning or the communication ID of the ECM and transponder key ECU assembly do not match.

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

Note

B2799

Engine Immobiliser System Malfunction

One of the following conditions is met:

  • Error in communication between ECM and transponder key ECU assembly.

  • Error in communication lines.

  • Communication ID is different during communication between ECM and transponder key ECU assembly.

  • Wire harness or connector

  • Transponder key ECU assembly

  • ECM

  • DTC Output Confirmation Operation:

  • Start the engine and wait 10 seconds.

  • After disconnecting and reconnecting the cable to the negative (-) battery terminal, turn the ignition switch to ON and wait 10 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

-
Table 2. Related Data List and Active Test

DTC No.

Data List and Active Test

B2799

-

WIRING DIAGRAM

B506729E02

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".

Tip:

If transponder key ECU assembly DTCs are output simultaneously, troubleshoot the transponder key ECU assembly DTCs first.

PROCEDURE

  1. CLEAR DTC

    1. Clear the DTCs.

      Powertrain > Engine and ECT > Clear DTCs

    Result

    Proceed to

    NEXT
    NEXT

  2. 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

    Result

    Proceed to

    OK

    A

    NG (DTC B2799 is output)

    B

    NG (Other DTCs are output)

    C
    A

    USE SIMULATION METHOD TO CHECK

    Click here

    C

    GO TO DIAGNOSTIC TROUBLE CODE CHART

    B

  3. INSPECT ECM (TERMINAL IMO)

    1. Using an oscilloscope, check the waveform.

      B506734C01

      *a

      Component with harness connected

      (ECM)

      *b

      Waveform
      Table 3. OK

      Tester Connection

      Condition

      Tool Setting

      Specified Condition

      A34-43 (IMO) - Body ground

      Within 3 seconds of starter operation and initial combustion, or within 3 seconds of ignition switch first being turned to ON after cable disconnected and reconnected to negative (-) battery terminal

      2 V/DIV., 500 ms./DIV.

      Pulse generation

      (See waveform)

    OK

    Waveform is similar to that shown in the illustration.

    Result

    Result

    Proceed to

    OK

    A

    NG (Terminal IMO stuck low (2.4 V or less))

    B

    NG (Terminal IMO stuck high (12 V) or abnormal waveform)

    C
    B

    INSPECT ECM (IMO TERMINAL VOLTAGE)Click here

    C

    REPLACE ECMClick here

    A

  4. INSPECT ECM (TERMINAL IMI)

    1. Using an oscilloscope, check the waveform.

      B506735C01

      *a

      Component with harness connected (ECM)

      *b

      Waveform
      Table 4. OK

      Tester Connection

      Condition

      Tool Setting

      Specified Condition

      A34-42 (IMI) - Body ground

      Within 3 seconds of starter operation and initial combustion, or within 3 seconds of ignition switch first being turned to ON after cable disconnected and reconnected to negative (-) battery terminal

      2 V/DIV., 500 ms./DIV.

      Pulse generation

      (See waveform)

    OK

    Waveform is similar to that shown in the illustration.

    Result

    Proceed to

    OK

    NG
    NG

    REPLACE TRANSPONDER KEY ECU ASSEMBLYClick here

    OK

  5. REGISTER ECU COMMUNICATION ID

    1. Reregister the ECU communication ID.

      Tip:

      Refer to Service Bulletin.

    Result

    Proceed to

    NEXT
    NEXT

  6. CHECK WHETHER ENGINE STARTS

    1. Using a registered door control transmitter assembly, turn the ignition switch to ON.

    2. Check that the engine starts 5 seconds after the ignition switch was turned to ON.

      OK

      Engine starts normally.

    Result

    Proceed to

    OK

    NG
    OK

    END (COMMUNICATION ID REGISTRATION WAS DEFECTIVE)

    NG

    REPLACE ECMClick here

  7. INSPECT ECM (IMO TERMINAL VOLTAGE)

    1. Disconnect the A34 ECM connector.

    2. Turn the ignition switch to ON.

    3. B506730C01

      *a

      Front view of wire harness connector

      (to ECM)

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

      Standard Voltage

      Tester Connection

      Condition

      Result

      A34-43 (IMO) - Body ground

      Ignition switch turned to ON using registered door control transmitter assembly

      Terminal IMO stuck low (2.4 V or less)

    Result

    Result

    Proceed to

    Terminal IMO stuck low (2.4 V or less)

    A

    Terminal IMO stuck high (12 V) or abnormal waveform

    B
    B

    REPLACE ECMClick here

    A

  8. CHECK HARNESS AND CONNECTOR (TRANSPONDER KEY ECU ASSEMBLY - ECM)

    1. Disconnect the E24 transponder key ECU assembly connector.

    2. Disconnect the A34 ECM connector.

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

      Standard Resistance

      Tester Connection

      Condition

      Specified Condition

      E24-12 (EFII) - A34-43 (IMO)

      Always

      Below 1 Ω

      A34-43 (IMO) or E24-12 (EFII) - Body ground

      Always

      10 kΩ or higher

    Result

    Proceed to

    OK

    NG
    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  9. REPLACE TRANSPONDER KEY ECU ASSEMBLY

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

      Tip:

      Refer to Service Bulletin.

      Note:

      Key ID code registration is necessary when replacing the transponder key ECU assembly, refer to Service Bulletin.

    Result

    Proceed to

    NEXT
    NEXT

  10. CHECK WHETHER ENGINE STARTS

    1. Using a registered door control transmitter assembly, turn the ignition switch to ON.

    2. Check that the engine starts 5 seconds after the ignition switch was turned to ON.

      OK

      Engine starts normally.

    Result

    Proceed to

    OK

    NG
    OK

    END (TRANSPONDER KEY ECU ASSEMBLY WAS DEFECTIVE)

    NG

    REPLACE ECM

    Click here

  11. REPLACE ECM

    1. Temporarily replace the ECM with a new one.

      Click here

    Result

    Proceed to

    NEXT
    NEXT

  12. REGISTER ECU COMMUNICATION ID

    1. Reregister the ECU communication ID.

      Tip:

      Refer to Service Bulletin.

    Result

    Proceed to

    NEXT
    NEXT

  13. CHECK WHETHER ENGINE STARTS

    1. Using a registered door control transmitter assembly, turn the ignition switch to ON.

    2. Check that the engine starts 5 seconds after the ignition switch was turned to ON.

      OK

      Engine starts normally.

    Result

    Proceed to

    OK

    NG
    OK

    END (ECM WAS DEFECTIVE)

    NG

    REPLACE TRANSPONDER KEY ECU ASSEMBLY