IMMOBILISER SYSTEM(w/o 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 key into the ignition key cylinder.
Table 1. Vehicle Condition and Fail-safe Operation when Malfunction Detected

Vehicle Condition when Malfunction Detected

Fail-safe Operation when Malfunction Detected

Engine cannot be started

-
Table 2. Related Data List and Active Test

DTC No.

Data List and Active Test

B2784

Antenna Coil Status

WIRING DIAGRAM

B329324E09

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. Check for DTCs.

      Body Electrical > Immobiliser > Trouble Codes

      Tip:

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

      OK

      DTC B2784 is not output.

    Result

    Result

    Proceed to

    B2784 is not output

    A

    B2784 is output

    B

  3. CHECK CONNECTION OF CONNECTOR

    1. Check that the connectors are 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. Check for DTCs.

      Body Electrical > Immobiliser > Trouble Codes

      Tip:

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

      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.

      B329326C05

      *a

      Component with harness connected

      (Transponder Key Coil)

      *b

      Waveform 1

      *c

      Waveform 2

      -

      -
      Table 3. Waveform 1

      Item

      Content

      Tester Connection

      E78-1 (ANT1) ←→ Body ground

      Tool Setting

      2 V/DIV., 500 ms./DIV.

      Condition

      Within 3 seconds of inserting key into ignition key cylinder
      Table 4. Waveform 2

      Item

      Content

      Tester Connection

      E78-5 (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

    Result

    Proceed to

    OK

    NG
    NG

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

    OK

  7. REPLACE TRANSPONDER KEY ECU ASSEMBLY

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

      Tip:

      Refer to Service Bulletin.

      Note:

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

      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. Check for DTCs.

      Body Electrical > Immobiliser > Trouble Codes

      Tip:

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

      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

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

    1. Disconnect the E21 transponder key ECU assembly connector.

    2. Disconnect the E78 transponder key coil connector.

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

      Standard Resistance

      Tester Connection

      Condition

      Specified Condition

      E21-4 (ANT1) - E78-1 (ANT1)

      Always

      Below 1 Ω

      E21-15 (ANT2) - E78-5 (ANT2)

      Always

      Below 1 Ω

      E21-4 (ANT1) - Body ground

      Always

      10 kΩ or higher

      E78-1 (ANT1) - Body ground

      Always

      10 kΩ or higher

      E21-15 (ANT2) - Body ground

      Always

      10 kΩ or higher

      E78-5 (ANT2) - Body ground

      Always

      10 kΩ or higher

    Result

    Proceed to

    OK

    NG
    OK

    REPLACE TRANSPONDER KEY ECU ASSEMBLYClick here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR