ENGINE IMMOBILISER SYSTEM, Diagnostic DTC:B2797

DTC Code DTC Name
B2797 Communication Malfunction No. 1

DESCRIPTION

This DTC is output when a communication error occurs between the transponder key amplifier and transponder key ECU. Some possible reasons for the communication error are: 1) 2 or more ignition keys are positioned too close together, or 2) noise is occurring in the communication line.

DTC No. DTC Detection Condition Trouble Area
B2797 Keys are positioned too close to each other, or noise occurred in communication line

  • Key

  • Wire Harness

  • Transponder key amplifier

  • Transponder key ECU

WIRING DIAGRAM

A01BHDEE17

INSPECTION PROCEDURE

PROCEDURE


  1. CHECK KEY


    1. A01BBKQE02

      Check if the ignition key being used is near other ignition keys. Also, check if the key ring is in contact with the key grip.

      Result:
      Result Proceed to
      Key is near other keys and/or key ring is in contact with key grip A
      Key is not near other keys and/or key ring is not in contact with key grip B

    B

    INSPECT TRANSPONDER KEY ECU Click here

    A

  2. CHECK FOR DTC


    1. Separate the keys from each other and/or remove the key ring.

    2. Delete the DTC Click here.

    3. Insert a key into the ignition key cylinder. Then remove it. Repeat for all the other keys.

    4. Check that no code is output.

      OK
      No code is output.

    OK

    END

    NG

  3. INSPECT TRANSPONDER KEY ECU


    1. A01BFETE14

      Using an oscilloscope or the intelligent tester, check for noise in the waveform between the terminals of the H43 transponder key amplifier connector and H60 transponder key ECU connector.

      OK
      No noise is present (see illustration).
      Tester Connection Tool Setting Condition Specified Condition
      H60-15 (CODE) - H43-4 (CODE) 5 V/DIV., 20 msec./DIV. Key inserted No noise is present

    NG

    FIND CAUSE OF NOISE AND REMOVE IT

    OK

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


    1. A01BAY7E58

      Disconnect the H60 transponder key ECU connector.

    2. Disconnect the H43 transponder key amplifier connector.

    3. Check the resistance.

      Standard resistance (Check for open)
      Tester Connection Specified Condition
      H60-15 (CODE) - H43-4 (CODE) Below 1 Ω
      Standard resistance (Check for short)
      Tester Connection Specified Condition
      H60-15 (CODE) or H43-4 (CODE) - Body ground 10 kΩ or higher

    4. Reconnect the transponder key amplifier connector.

    5. Reconnect the transponder key ECU connector.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  5. CHECK TRANSPONDER KEY AMPLIFIER (OPERATION)


    1. After replacing the transponder key amplifier with a normally functioning amplifier, check that the engine starts.

      OK
      Engine starts.

    NG

    REPLACE TRANSPONDER KEY ECU

    OK

    END (TRANSPONDER KEY AMPLIFIER DEFECTIVE)