ENGINE IMMOBILISER SYSTEM (w/o Smart Entry and Start System), Diagnostic DTC:B2793, B2794, B2797, B2798

DTC Code DTC Name
B2793 Transponder Chip Malfunction
B2794 Unmatched Encryption Code
B2797 Communication Malfunction No. 1
B2798 Communication Malfunction No. 2

DESCRIPTION


DTC No. DTC Detection Condition Trouble Area DTC Output Confirmation Operation
B2793 A transponder chip malfunction (1 trip detection logic*).

  • Key

  • Transponder key coil

  • Transponder key ECU assembly

 Insert the key into the ignition key cylinder
B2794 A key with an incomplete key ID code is inserted into the ignition key cylinder (1 trip detection logic*).

  • Key

  • Transponder key coil

  • Transponder key ECU assembly

 Insert the key into the ignition key cylinder
B2797 A key with a BCC malfunction is inserted into the ignition key cylinder (1 trip detection logic*).

  • Key

  • Transponder key coil

  • Transponder key ECU assembly

 Insert the key into the ignition key cylinder
B2798 Key ID code identification cannot be completed within the specified time (1 trip detection logic*).

  • Key

  • Transponder key coil

  • Transponder key ECU assembly

 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 No. Data List and Active Test
B2793 -
B2794 -
B2797 -
B2798 -

INSPECTION PROCEDURE

Note


  • If the transponder key ECU assembly or key is replaced, refer to Service Bulletin.

  • After repair, confirm that no DTCs are output by performing "DTC Output Confirmation Operation".

  • When using the GTS with the vehicle ignition switch off, connect the GTS to the vehicle 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 the Model Code "KEY REGIST" under manual mode and enter the following menus: Body Electrical / Immobiliser. 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.

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 DTCs each time Click here.

      Tech Tips


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

      • If DTCs B2793, B2794, B2797, or B2798 are stored, clear the DTCs before checking the next key.

      OK
      DTCs B2793, B2794, B2797 and B2798 are not output.
      Result
      Result Proceed to
      DTCs are not output A
      DTCs are output for all of the keys B
      DTCs are output for any of the keys C

    B

    CHECK CONNECTION OF CONNECTOR Click here

    C

    REPLACE KEY FOR WHICH DTC WAS OUTPUT

    A

    USE SIMULATION METHOD TO CHECK Click here

  3. CHECK CONNECTION OF CONNECTOR


    1. Check that the connectors are properly connected to the transponder key coil.

    2. Check that the engine starts with the key.

      OK
      Engine starts.

    NG

    CHECK TRANSPONDER KEY COIL Click here

    OK

    END (CONNECTOR WAS NOT CONNECTED PROPERLY)

  4. CHECK TRANSPONDER KEY COIL


    1. Clear the DTCs Click here.

    2. Temporarily replace the transponder key coil with a new one or known good one Click here.

    3. Check that the engine starts with the key.

      OK
      Engine starts.

    NG

    REPLACE TRANSPONDER KEY ECU ASSEMBLY

    OK

    END (TRANSPONDER KEY COIL WAS DEFECTIVE)