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

DTC Code DTC Name
B2784 Antenna Coil Open / Short

DESCRIPTION

When an open or short circuit is detected in the antenna coil built into the transponder key coil, the transponder key ECU assembly stores this DTC.

DTC No. DTC Detection Condition Trouble Area DTC Output Confirmation Operation
B2784 The antenna coil in the transponder key coil is open/shorted.

  • Harness or connector

  • Transponder key coil

  • 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 No. Data List and Active Test
B2784 Antenna Coil Status

WIRING DIAGRAM

B007VERE02

INSPECTION PROCEDURE

Note


  • If the transponder key ECU assembly is replaced, refer to Service Bulletin.

  • After repair, confirm that no DTCs are output by performing "DTC Output Confirmation Operation".

  • When using the GTS with the vehicle ignition switch off, connect the GTS to the vehicle and turn a courtesy light switch on and off at intervals of 1.5 seconds or less until communication between the GTS and the vehicle begins. Then select the Model Code "KEY REGIST" under manual mode and enter the following menus: Body Electrical / Immobiliser. While using the GTS, periodically turn a courtesy light switch on and off at intervals of 1.5 seconds or less to maintain communication between the GTS and the vehicle.

PROCEDURE


  1. CLEAR DTC


    1. Clear the DTCs Click here.


    NEXT

  2. CHECK FOR DTC


    1. Check for DTCs Click here.

      Tech Tips

      Before checking for DTCs, perform the "DTC Output Confirmation Operation" procedure.

      OK
      DTC B2784 is not output.

    NG

    CHECK CONNECTION OF CONNECTOR Click here

    OK

    USE SIMULATION METHOD TO CHECK Click here

  3. CHECK CONNECTION OF CONNECTOR


    1. Check that the connectors are properly connected to the transponder key coil.


    NEXT

  4. CLEAR DTC


    1. Clear the DTCs Click here.


    NEXT

  5. CHECK FOR DTC


    1. Check for DTCs Click here.

      Tech Tips

      Before checking for DTCs, perform the "DTC Output Confirmation Operation" procedure.

      OK
      DTC B2784 is not output.

    NG

    CHECK TRANSPONDER KEY COIL (OUTPUT) Click here

    OK

    END (CONNECTOR WAS NOT CONNECTED PROPERLY)

  6. CHECK TRANSPONDER KEY COIL (OUTPUT)


    1. Using an oscilloscope, check the waveform.

      B007VQOE03
      Text in Illustration
      *a

      Component with harness connected

      (Transponder Key Coil)

      		 *b Waveform 1
      *c Waveform 2 - -
      Waveform 1
      Item Content
      Tester Connection H79-1 (ANT1) - Body ground
      Tool Setting 2 V/DIV., 500 ms/DIV
      Condition Within 3 seconds of inserting key into ignition key cylinder
      Waveform 2
      Item Content
      Tester Connection F79-5 (ANT2) - Body ground
      Tool Setting 2 V/DIV., 500 ms/DIV
      Tool Setting Within 3 seconds of inserting key into ignition key cylinder
      OK
      Waveform is similar to that shown in the illustration.

    NG

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

    OK

  7. REPLACE TRANSPONDER KEY ECU ASSEMBLY


    1. Replace the transponder key ECU assembly with a new one.

      Tech Tips

      Refer to Service Bulletin.

      Note

      Key ID code registration is necessary when replacing the transponder key ECU assembly.

      Refer to Service Bulletin.


    NEXT

  8. CLEAR DTC


    1. Clear the DTCs Click here.


    NEXT

  9. CHECK FOR DTC


    1. Check for DTCs Click here.

      Tech Tips

      Before checking for DTCs, perform the "DTC Output Confirmation Operation" procedure.

      OK
      DTC B2784 is not output.

    NG

    REPLACE TRANSPONDER KEY COIL Click here

    OK

    END (TRANSPONDER KEY ECU ASSEMBLY WAS DEFECTIVE)

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


    1. Disconnect the H60 transponder key ECU assembly connector.

    2. Disconnect the H79 transponder key coil connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      H60-4 (ANT1) - H79-1 (ANT1) Always Below 1 Ω
      H60-15 (ANT2) - H79-5 (ANT2) Always Below 1 Ω
      H60-4 (ANT1) - Body ground Always 10 kΩ or higher
      H79-1 (ANT1) - Body ground Always 10 kΩ or higher
      H60-15 (ANT2) - Body ground Always 10 kΩ or higher
      H79-5 (ANT2) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  11. REPLACE TRANSPONDER KEY ECU ASSEMBLY


    1. Replace the transponder key ECU assembly with a new one.

      Tech Tips

      Refer to Service Bulletin.

      Note

      Key ID code registration is necessary when replacing the transponder key ECU assembly.

      Refer to Service Bulletin.


    NEXT

  12. CLEAR DTC


    1. Clear the DTCs Click here.


    NEXT

  13. CHECK FOR DTC


    1. Check for DTCs Click here.

      Tech Tips

      Before checking for DTCs, perform the "DTC Output Confirmation Operation" procedure.

      OK
      DTC B2784 is not output.

    NG

    REPLACE TRANSPONDER KEY COIL Click here

    OK

    END (TRANSPONDER KEY ECU ASSEMBLY WAS DEFECTIVE)