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

DTC Code DTC Name
B2784 Antenna Coil Open / Short

DESCRIPTION

The transponder key coil is built into the transponder key amplifier and receives a key code signal from the transponder chip in the key. This signal is amplified by the amplifier, then it is output to the transponder key ECU assembly.

DTC No. DTC Detection Condition Trouble Area
B2784 Antenna coil is open/shorted

  • Wire harness or connector

  • Transponder key amplifier

  • Transponder key ECU assembly

WIRING DIAGRAM

A017E3WE07

INSPECTION PROCEDURE

Note

If the transponder key ECU is replaced, register the key and ECU communication ID.

PROCEDURE


  1. READ VALUE ON INTELLIGENT TESTER (TRANSPONDER KEY AMPLIFIER)


    1. Connect the intelligent tester to the DLC3.

    2. Turn the ignition switch to the ON position.

    3. Turn the tester on.

    4. Select Antenna Coil Status in the Data List and read the tester display.

      Immobiliser (Transponder Key ECU):
      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Antenna Coil Status Transponder key amplifier coil condition/NORMAL or FAIL

      NORMAL: Antenna coil is normal

      FAIL: Antenna coil is malfunctioning

      		 -
      OK
      NORMAL (Antenna coil is normal) appears on the screen.

    NG

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

    OK

    REPLACE TRANSPONDER KEY ECU ASSEMBLY

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


    1. A017FSNE06

      Disconnect the transponder key ECU and transponder key amplifier connectors.

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

      Standard resistance
      Tester Connection Condition Specified Condition
      D37-4 (TXCT) - D24-5 (TXCT) Always Below 1 Ω
      D37-5 (AGND) - D24-7 (AGND) Always Below 1 Ω
      D37-14 (VC5) - D24-1 (VC5) Always Below 1 Ω
      D37-15 (CODE) - D24-4 (CODE) Always Below 1 Ω
      D37-4 (TXCT) - Body ground Always 10 kΩ or higher
      D37-5 (AGND) - Body ground Always 10 kΩ or higher
      D37-14 (VC5) - Body ground Always 10 kΩ or higher
      D37-15 (CODE) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  3. INSPECT TRANSPONDER KEY ECU ASSEMBLY (TRANSPONDER KEY AMPLIFIER POWER SOURCE)


    1. A017DIJE30

      Reconnect the transponder key ECU and transponder key amplifier connectors.

    2. Measure the voltage according to the value(s) in the table below.

      Standard voltage
      Tester Connection Condition Specified Condition
      D37-14 (VC5) - Body ground No key is in ignition key cylinder Below 1 V
      D37-14 (VC5) - Body ground Key is in ignition key cylinder 4.6 to 5.4 V

    NG

    REPLACE TRANSPONDER KEY ECU ASSEMBLY

    OK

  4. INSPECT TRANSPONDER KEY ECU ASSEMBLY (TRANSPONDER KEY AMPLIFIER GROUND)


    1. A017DIJE32

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

      Standard resistance
      Tester Connection Condition Specified Condition
      D37-5 (AGND) - Body ground Always Below 1 Ω

    NG

    REPLACE TRANSPONDER KEY ECU ASSEMBLY

    OK

    REPLACE TRANSPONDER KEY AMPLIFIER Click here