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

DTC Code DTC Name
B2797 Communication Malfunction No. 1

DESCRIPTION

This DTC is stored when a communication error occurs between the transponder key amplifier and transponder key ECU assembly. 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 Code DTC Detection Condition Trouble Area
B2797 2 or more ignition keys are positioned too close to each other or noise occurs in the communication line.

  • Key

  • Harness or connector

  • Transponder key amplifier

  • Transponder key ECU assembly

WIRING DIAGRAM

A00O38QE15

INSPECTION PROCEDURE

Note

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

PROCEDURE


  1. CHECK KEY


    1. A00OB93

      Check whether the ignition key being used is near other ignition keys, as shown in the illustration. Also, check whether a 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 key ring is not in contact with key grip B

    B

    CHECK HARNESS AND CONNECTOR (TRANSPONDER KEY ECU - TRANSPONDER KEY AMPLIFIER) Click here

    A

  2. CHECK FOR DTC


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

    2. Clear the DTCs Click here.

    3. Insert a key into the ignition key cylinder, and then remove it. Repeat this for all the other keys.

    4. Check that no DTC is output Click here.

      OK
      DTC B2797 is not output.

    NG

    CHECK HARNESS AND CONNECTOR (TRANSPONDER KEY ECU - TRANSPONDER KEY AMPLIFIER) Click here

    OK

    END

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


    1. Disconnect the G138*1 or G74*2 ECU connector.


      • *1: for 5L-E

      • *2: except 5L-E

    2. Disconnect the G75 amplifier connector.

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

      Standard Resistance
      for 5L-E
      Tester Connection Condition Specified Condition
      G138-15 (CODE) - G75-4 (CODE) Always Below 1 Ω
      G138-15 (CODE) or G75-4 (CODE) - Body ground Always 10 kΩ or higher
      except 5L-E
      Tester Connection Condition Specified Condition
      G74-15 (CODE) - G75-4 (CODE) Always Below 1 Ω
      G74-15 (CODE) or G75-4 (CODE) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  4. CHECK TRANSPONDER KEY ECU ASSEMBLY (NOISE)


    • *1: for 5L-E

    • *2: except 5L-E


    1. A00O9JAE03
      Text in Illustration
      *A for 5L-E
      *B except 5L-E
      *a

      Component with harness connected

      (Transponder Key Amplifier)
      *b

      Component with harness connected

      (Transponder Key ECU Assembly)
      *c Noise should not appear

      Using an oscilloscope, check for noise in the waveform between the terminals of the G75 amplifier connector and G138*1 or G74*2 ECU connector.

      Measurement Condition
      Item Content
      Tester Connection

      G75-4 (CODE) - G138-15 (CODE)*1

      G75-4 (CODE) - G74-15 (CODE)*2
      Tool Setting 5 V/DIV., 20 ms./DIV.
      Condition Key inserted in ignition key cylinder
      OK
      No noise is present.

    NG

    FIND CAUSE OF NOISE AND REMOVE IT

    OK

  5. REPLACE TRANSPONDER KEY AMPLIFIER


    1. Temporarily replace the transponder key amplifier with a new or normally functioning one Click here.


    NEXT

  6. CHECK WHETHER ENGINE STARTS


    1. Check that the engine starts normally.

      OK
      Engine starts.

    NG

    REPLACE TRANSPONDER KEY ECU ASSEMBLY

    OK

    END (TRANSPONDER KEY AMPLIFIER IS DEFECTIVE)