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

B004MFVE17
*a Transponder Key Coil
*b Transponder Key ECU Assembly

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. CHECK CONNECTION OF CONNECTOR


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

      Result
      Proceed to
      NEXT

    NEXT

  2. CLEAR DTC


    1. Clear the DTCs.


      Body Electrical > Immobiliser > Clear DTCs
      Result
      Proceed to
      NEXT

    NEXT

  3. 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

  4. CHECK TRANSPONDER KEY COIL (OUTPUT)


    1. Disconnect the K61 transponder key coil connector.

    2. Using an oscilloscope, check the waveform.

      B004MYAC01
      *a

      Front view of wire harness connector

      (to Transponder Key Coil)

      		 *b Waveform 1
      *c Waveform 2 - -
      OK
      Tester Connection Condition Tool Setting Specified Condition
      K61-1 (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)
      K61-5 (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

    OK

    REPLACE TRANSPONDER KEY COIL Click here

    NG

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


    1. Disconnect the K60 transponder key ECU assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      K60-2 (ANT1) - K61-1 (ANT1) Always Below 1 Ω
      K60-3 (ANT2) - K61-5 (ANT2) Always Below 1 Ω
      K60-2 (ANT1) or K61-1 (ANT1) - Other terminals and body ground Always 10 kΩ or higher
      K60-3 (ANT2) or K61-5 (ANT2) - Other terminals and body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE TRANSPONDER KEY ECU ASSEMBLY

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR