DTC    B2784    Antenna Coil Open / Short

for Preparation Click here


DESCRIPTION

The antenna coil receives key code signals from the transponder chip in the key grip, the coil is built in to the transponder key amplifier, which amplifies the key code signals and outputs the signals to the transponder key ECU. This DTC is stored when there is an open or short in the antenna coil.

DTC No.
DTC Detection Condition
Trouble Area
B2784
When performing immobiliser set/unset, the antenna coil circuit is opened or shorted for 5 seconds.
  1. Wire harness or connector
  2. Transponder key amplifier
  3. Transponder key ECU

WIRING DIAGRAM


B164252E17


INSPECTION PROCEDURE

NOTICE:
If the transponder key ECU is replaced, register the key and ECU - ECM communication ID.

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


    B203485E02

  1. Disconnect the D29 transponder key ECU connectors.

  1. Disconnect the D24 transponder key amplifier connector.

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

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    D29-4 (TXCT) - D31-5 (TXCT)
    		Always
    		Below 1 Ω
    D29-5 (AGND) - D31-7 (AGND)
    		Always
    		Below 1 Ω
    D29-14 (VC5) - D31-1 (VC5)
    		Always
    		Below 1 Ω
    D29-15 (CODE) - D31-4 (CODE)
    		Always
    		Below 1 Ω
    D29-4 (TXCT) - Body ground
    		Always
    		10 kΩ or higher
    D29-5 (AGND) - Body ground
    		Always
    		10 kΩ or higher
    D29-14 (VC5) - Body ground
    		Always
    		10 kΩ or higher
    D29-15 (CODE) - Body ground
    		Always
    		10 kΩ or higher

  1. Reconnect the amplifier and ECU connector.
    Text in Illustration 
    *1
    		Front view of wire harness connector
    (to Transponder Key ECU)
    *2
    		Front view of wire harness connector
    (to Transponder Key Amplifier)



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


2.INSPECT TRANSPONDER KEY ECU (TRANSPONDER KEY AMPLIFIER POWER SOURCE AND GROUND)
B203486E02

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

    Standard Voltage:
    Tester Connection
    		Condition
    		Specified Condition
    D29-14 (VC5) - Body ground
    		No key is in ignition key cylinder
    		Below 1 V
    Key is in ignition key cylinder
    		4.6 to 5.4 V
    D29-5 (AGND) - Body ground
    		Always
    		Below 1 Ω

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

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    D29-5 (AGND) - Body ground
    		Always
    		Below 1 Ω

Text in Illustration 
*1
Component with harness connected
(Transponder Key ECU)


NG
REPLACE TRANSPONDER KEY ECU
OK


3.REPLACE TRANSPONDER KEY AMPLIFIER

  1. Temporarily replace the transponder key amplifier with a new or normally functioning one (Click here).


NEXT


4.CLEAR DTC

  1. Clear the DTC (Click here).


NEXT


5.CHECK FOR DTC

  1. Check for DTCs (Click here).

    OK:
    DTC B2784 is not output.



NG
REPLACE TRANSPONDER KEY ECU
OK

END (TRANSPONDER KEY AMPLIFIER IS DEFECTIVE)