ENGINE IMMOBILISER SYSTEM(w/o Entry and Start System), Diagnostic DTC:B2784

DTC Code DTC Name
B2784 Antenna Coil Open / Short

DESCRIPTION

The antenna coil receives key code signals from the transponder chip in the key grip. The antenna coil is built into the transponder key amplifier, which amplifies the key code signals and outputs the signals to the transponder key ECU assembly.

This DTC is stored when there is an open or short in the antenna coil.

DTC Code DTC Detection Condition Trouble Area DTC Output Confirmation Operation
B2784

The antenna coil built into the transponder key amplifier is open or shorted (determined by communication with transponder key ECU assembly) (1 trip detection logic*).


  • Terminal VC5, TXCT or CODE is open.

  • The antenna coil built into the transponder key amplifier is open.

  • Harness or connector

  • Transponder key amplifier

  • 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 Code Data List and Active Test
B2784 Antenna Coil Status

WIRING DIAGRAM

A005HY3E01
*a CODE
*b Antenna Coil
*c TRANSPONDER KEY AMPLIFIER
*d TRANSPONDER KEY ECU ASSEMBLY

CAUTION / NOTICE / HINT

Note


  • When replacing the transponder key ECU assembly, 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. Check for DTCs Click here.

      OK
      DTC B2784 is not output.

    OK

    USE SIMULATION METHOD TO CHECK Click here

    NG

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


    1. Disconnect the F54 transponder key ECU assembly connector.

    2. Disconnect the F55 transponder key amplifier connector.

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

      Standard Resistance (Check for Open)
      Tester Connection Condition Specified Condition
      F54-14 (VC5) - F55-1 (VC5) Always Below 1 Ω
      F54-15 (CODE) - F55-4 (CODE) Always Below 1 Ω
      F54-4 (TXCT) - F55-5 (TXCT) Always Below 1 Ω
      F54-5 (AGND) - F55-7 (AGND) Always Below 1 Ω
      Standard Resistance (Check for Short)
      Tester Connection Condition Specified Condition
      F54-14 (VC5) or F55-1 (VC5) - Body ground Always 10 kΩ or higher
      F54-15 (CODE) or F55-4 (CODE) - Body ground Always 10 kΩ or higher
      F54-4 (TXCT) or F55-5 (TXCT) - Body ground Always 10 kΩ or higher
      F54-5 (AGND) or F55-7 (AGND) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  4. REPLACE TRANSPONDER KEY AMPLIFIER


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


    NEXT

  5. CHECK FOR DTC


    1. Check for DTCs Click here.

      OK
      DTC B2784 is not output.

    OK

    END (TRANSPONDER KEY AMPLIFIER WAS DEFECTIVE)

    NG

    REPLACE TRANSPONDER KEY ECU ASSEMBLY