ENGINE IMMOBILISER SYSTEM, Diagnostic DTC:B2796, B2798

DTC Code DTC Name
B2796 No Communication in Immobiliser System
B2798 Communication Malfunction No. 2

DESCRIPTION

These DTCs are output when a key that does not have a transponder chip is inserted into the ignition key cylinder or communication between the key and transponder key ECU assembly is not possible.

DTC No. DTC Detection Conditions Trouble Areas
B2796 No response from inserted key

-Key

-Wire harness or connector

-Transponder key coil

-Transponder key ECU assembly
B2798 Communication error

Key

-Wire harness or connector

-Transponder key coil

-Transponder key ECU assembly

WIRING DIAGRAM

A0138BUE01

INSPECTION PROCEDURE

PROCEDURE


  1. CHECK WHETHER ENGINE STARTS WITH OTHER KEYS


    1. Check whether the engine can be started with the vehicle's other keys.

      OK
      Engine starts.

    OK

    RE-REGISTER OR REPLACE KEY THAT WILL NOT START ENGINE

    NG

  2. READ VALUE USING INTELLIGENT TESTER


    1. Connect the intelligent tester to the DLC3.

    2. Turn the ignition switch to ON with the key that will not start the engine.

    3. Select the following menu items: Body / immobiliser / Data List / Antenna Coil.

      OK
      NORMAL (antenna coil is normal) appears on the screen.
      Item Measurement Item: Display (Range) Normal Condition Diagnostic Note
      Antenna Coil

      Antenna coil condition:

      NORMAL or FAIL

      NORMAL: Antenna coil normal

      FAIL: Antenna coil abnormal

      		 -

    OK

    REPLACE TRANSPONDER KEY ECU ASSEMBLY

    NG

  3. CHECK HARNESS AND CONNECTOR (TRANSPONDER KEY ECU ASSEMBLY - TRANSPONDER KEY COIL)


    1. A0137FEE01

      Disconnect the C30 transponder key ECU assembly connector.

    2. Disconnect the C31 transponder key coil connector.

    3. Measure the resistance of the wire harness side connectors.

      Standard Resistance
      Tester Connection Specified Condition
      C30-4 (AN1) - C31-1 (AN1) Below 1 Ω
      C30-5 (AN2) - C31-2 (AN2) Below 1 Ω
      C30-4 (AN1) or C31-1 (AN1) - Body ground 10 kΩ higher
      C30-5 (AN2) or C31-2 (AN2) - Body ground 10 kΩ higher

    4. Reconnect the transponder key coil connector.

    5. Reconnect the transponder key ECU assembly connector.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  4. REPLACE TRANSPONDER KEY COIL


    NEXT

  5. CHECK OPERATION OF TRANSPONDER KEY COIL


    1. After replacing the transponder key coil check that the engine starts.

      OK
      Engine starts.

    NG

    REPLACE TRANSPONDER KEY ECU ASSEMBLY

    OK

    END