ENGINE IMMOBILISER SYSTEM(w/o Entry and Start System), Diagnostic DTC:B2796

DTC Code DTC Name
B2796 No Communication in Immobiliser System

DESCRIPTION


DTC Code DTC Detection Condition Trouble Area DTC Output Confirmation Operation
B2796 The key code cannot be transmitted (1 trip detection logic*).

  • Key

  • Harness or connector

  • Transponder key ECU assembly

  • Transponder key amplifier

 Insert the key into the ignition key cylinder.

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
B2796 Response

WIRING DIAGRAM

A01VJH7E09

CAUTION / NOTICE / HINT

Note


  • When replacing the transponder key ECU assembly or key, refer to the Service Bulletin.

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

PROCEDURE


  1. CLEAR DTC


    1. Clear the DTCs Click here.


    NEXT

  2. CHECK FOR DTC


    1. Insert and remove each registered key one at a time, and check for DTC each time Click here.

      Tech Tips


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

      • If DTC B2796 is stored, check for DTCs with the next key after clearing the DTCs.

      OK
      DTC B2796 is not output.
      Result
      Result Proceed to
      OK A
      NG (all keys) B
      NG (any key) C

    A

    USE SIMULATION METHOD TO CHECK Click here

    C

    REPLACE KEY THAT CANNOT START ENGINE

    B

  3. CHECK CONNECTION OF CONNECTOR


    1. Check the connection of the transponder key ECU assembly and transponder key amplifier connectors.

    2. Visually inspect the terminals of the transponder key ECU assembly and transponder key amplifier connectors.

      OK
      Connectors are properly connected.

    NG

    CONNECT CONNECTORS PROPERLY

    OK

  4. CHECK WHETHER ENGINE STARTS


    1. Check that the engine starts with an already registered vehicle key.

      OK
      Engine starts normally.

    NG

    CHECK TRANSPONDER KEY AMPLIFIER Click here

    OK

  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 B2796 is not output.

    OK

    END (CONNECTOR WAS NOT PROPERLY CONNECTED)

    NG

  7. CHECK TRANSPONDER KEY AMPLIFIER


    1. Using an oscilloscope, check the waveform.

      A01VM74E01

      1. Waveform 1 (Reference)

        Measurement Condition
        Item Content
        Tester Connection F55-1 (VC5) - Body ground
        Tool Setting 1 V/DIV., 20 ms./DIV.
        Condition Key inserted in ignition key cylinder

      2. Waveform 2 (Reference)

        Measurement Condition
        Item Content
        Tester Connection F55-5 (TXCT) - Body ground
        Tool Setting 1 V/DIV., 20 ms./DIV.
        Condition Key inserted in ignition key cylinder

      3. Waveform 3 (Reference)

        Measurement Condition
        Item Content
        Tester Connection F55-4 (CODE) - Body ground
        Tool Setting 1 V/DIV., 20 ms./DIV.
        Condition Key inserted in ignition key cylinder
        OK
        Waveform is output normally (refer to illustration).
        Text in Illustration
        *a

        Component with harness connected

        (Transponder Key Amplifier)
        *b Waveform 1
        *c Waveform 2
        *d Waveform 3
        Result
        Result Proceed to
        OK A
        NG (Waveform 1) B
        NG (Waveform 2) C
        NG (Waveform 3) D

    A

    REPLACE TRANSPONDER KEY ECU ASSEMBLY

    C

    CHECK TRANSPONDER KEY AMPLIFIER (TXCT) Click here

    D

    CHECK TRANSPONDER KEY AMPLIFIER (CODE) Click here

    B

  8. CHECK TRANSPONDER KEY AMPLIFIER (VC5)


    1. Disconnect the F55 transponder key amplifier connector.

    2. A01VEBCE01
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Transponder Key Amplifier)
      *b Waveform

      Using an oscilloscope, check the waveform.


      1. Waveform (Reference)

        Measurement Condition
        Item Content
        Tester Connection F55-1 (VC5) - Body ground
        Tool Setting 1 V/DIV., 20 ms./DIV.
        Condition Key inserted in ignition key cylinder
        OK
        Waveform is output normally (refer to illustration).

    OK

    REPLACE TRANSPONDER KEY AMPLIFIER Click here

    NG

  9. CHECK HARNESS AND CONNECTOR (TRANSPONDER KEY AMPLIFIER - TRANSPONDER KEY ECU ASSEMBLY)


    1. Disconnect the F55 transponder key amplifier connector.

    2. Disconnect the F54 transponder key ECU assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      F55-1 (VC5) - F54-14 (VC5) Always Below 1 Ω
      F55-7 (AGND) - F54-5 (AGND) Always Below 1 Ω
      F55-1 (VC5) - Body ground Always 10 kΩ or higher

    OK

    REPLACE TRANSPONDER KEY ECU ASSEMBLY

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

  10. CHECK TRANSPONDER KEY AMPLIFIER (TXCT)


    1. Disconnect the F55 transponder key amplifier connector.

    2. A01VIHJE01
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Transponder Key Amplifier)
      *b Waveform

      Using an oscilloscope, check the waveform.


      1. Waveform (Reference)

        Measurement Condition
        Item Content
        Tester Connection F55-5 (TXCT) - Body ground
        Tool Setting 1 V/DIV., 20 ms./DIV.
        Condition Key inserted in ignition key cylinder
        OK
        Waveform is output normally (refer to illustration).

    OK

    REPLACE TRANSPONDER KEY AMPLIFIER Click here

    NG

  11. CHECK HARNESS AND CONNECTOR (TRANSPONDER KEY AMPLIFIER - TRANSPONDER KEY ECU ASSEMBLY)


    1. Disconnect the F55 transponder key amplifier connector.

    2. Disconnect the F54 transponder key ECU assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      F55-5 (TXCT) - F54-4 (TXCT) Always Below 1 Ω
      F55-5 (TXCT) - Body ground Always 10 kΩ or higher

    OK

    REPLACE TRANSPONDER KEY ECU ASSEMBLY

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

  12. CHECK TRANSPONDER KEY AMPLIFIER (CODE)


    1. Disconnect the F55 transponder key amplifier connector.

    2. A01VE0CE01
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Transponder Key Amplifier)
      *b Waveform

      Using an oscilloscope, check the waveform.


      1. Waveform (Reference)

        Measurement Condition
        Item Content
        Tester Connection F55-4 (CODE) - Body ground
        Tool Setting 1 V/DIV., 20 ms./DIV.
        Condition Key inserted in ignition key cylinder
        OK
        Waveform is output normally (refer to illustration).

    OK

    REPLACE TRANSPONDER KEY AMPLIFIER Click here

    NG

  13. CHECK HARNESS AND CONNECTOR (TRANSPONDER KEY AMPLIFIER - TRANSPONDER KEY ECU ASSEMBLY)


    1. Disconnect the F55 transponder key amplifier connector.

    2. Disconnect the F54 transponder key ECU assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      F55-4 (CODE) - F54-15 (CODE) Always Below 1 Ω
      F55-4 (CODE) - Body ground Always 10 kΩ or higher

    OK

    REPLACE TRANSPONDER KEY ECU ASSEMBLY

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR