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. Detection Item DTC Detection Condition Trouble Area Note
B2784 Antenna Coil Open / Short The antenna coil in the transponder key coil is open/shorted.

  • Wire harness or connector

  • Transponder key coil

  • Transponder key ECU assembly

    DTC Output Confirmation Operation:

  • Insert the door control transmitter assembly 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

A0026XME24
*a Transponder Key ECU Assembly
*b Transponder Key Coil

CAUTION / NOTICE / HINT

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".

PROCEDURE


  1. CLEAR DTC


    1. Clear the DTCs.


      Body Electrical > Immobiliser > Clear DTCs
      Result
      Proceed to
      NEXT

    NEXT

  2. CHECK FOR DTC


    1. Perform "DTC Output Confirmation Operation" procedure.

    2. Check for DTCs.


      Body Electrical > Immobiliser > Trouble Codes
      OK
      DTC B2784 is not output.
      Result
      Result Proceed to
      B2784 is not output A
      B2784 is output B

    A

    USE SIMULATION METHOD TO CHECK Click here

    B

  3. CHECK CONNECTION OF CONNECTOR


    1. Check that the connector is properly connected to the transponder key coil.

      Result
      Proceed to
      NEXT

    NEXT

  4. CLEAR DTC


    1. Clear the DTCs.


      Body Electrical > Immobiliser > Clear DTCs
      Result
      Proceed to
      NEXT

    NEXT

  5. CHECK FOR DTC


    1. Perform "DTC Output Confirmation Operation" procedure.

    2. Check for DTCs.


      Body Electrical > Immobiliser > Trouble Codes
      OK
      DTC B2784 is not output.
      Result
      Result Proceed to
      B2784 is not output A
      B2784 is output B

    A

    END (CONNECTOR WAS NOT CONNECTED PROPERLY)

    B

  6. CHECK TRANSPONDER KEY COIL (OUTPUT)


    1. Using an oscilloscope, check the waveform.

      A002BWLC14
      *a

      Component with harness connected

      (Transponder Key Coil)

      		 *b Waveform 1
      *c Waveform 2 - -
      Measurement Condition
      Tester Connection Condition Tool Setting Specified Condition
      F53-1 (ANT1) - Body ground Within 3 seconds of inserting door control transmitter assembly into ignition key cylinder 2 V/DIV., 500 ms./DIV.

      Pulse generation

      (See waveform 1)
      F53-5 (ANT2) - Body ground Within 3 seconds of inserting door control transmitter assembly into ignition key cylinder 2 V/DIV., 500 ms./DIV.

      Pulse generation

      (See waveform 2)
      OK
      Waveform is similar to that shown in the illustration.
      Result
      Proceed to
      OK
      NG

    NG

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

    OK

  7. REPLACE TRANSPONDER KEY ECU ASSEMBLY


    1. Temporarily replace the transponder key ECU assembly with a new one.

      Note

      Key ID code registration is necessary when replacing the transponder key ECU assembly, refer to Service Bulletin.

      Tech Tips

      Refer to Service Bulletin.

      Result
      Proceed to
      NEXT

    NEXT

  8. CLEAR DTC


    1. Clear the DTCs.


      Body Electrical > Immobiliser > Clear DTCs
      Result
      Proceed to
      NEXT

    NEXT

  9. CHECK FOR DTC


    1. Perform "DTC Output Confirmation Operation" procedure.

    2. Check for DTCs.


      Body Electrical > Immobiliser > Trouble Codes
      OK
      DTC B2784 is not output.
      Result
      Result Proceed to
      B2784 is not output A
      B2784 is output B

    A

    END (TRANSPONDER KEY ECU ASSEMBLY WAS DEFECTIVE)

    B

    REPLACE TRANSPONDER KEY COIL Click here

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


    1. Disconnect the F66 transponder key ECU assembly connector.

    2. Disconnect the F53 transponder key coil connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      F66-4 (ANT1) - F53-1 (ANT1) Always Below 1 Ω
      F66-15 (ANT2) - F53-5 (ANT2) Always Below 1 Ω
      F66-4 (ANT1) or F53-1 (ANT1) - Body ground Always 10 kΩ or higher
      F66-15 (ANT2) or F53-5 (ANT2) - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    OK

    GO TO STEP 7 Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR