Toyota Avalon Service & Repair Manual: Antenna Coil Open / Short (B2784)

DESCRIPTION

When an open or short circuit is detected in the transponder key amplifier coil built into the power switch, the certification ECU (smart key ECU assembly) stores this DTC. This DTC is also stored as a history DTC.

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

Note

B2784

Antenna Coil Open / Short

The transponder key amplifier coil built into the power switch is open (see below) or shorted (determined by communication with certification ECU (smart key ECU assembly)). (1 trip detection logic*)

  • Power switch
  • Certification ECU (smart key ECU assembly)
  • Wire harness or connector

DTC output confirmation operation:

  • With the shift lever in P and the electrical key transmitter sub-assembly held near the power switch, a hybrid control system start operation is performed by pressing and holding the power switch when the transmitter battery is depleted.
  • *: Only output while a malfunction is present.
Vehicle Condition and Fail-safe Operation when Malfunction Detected

Vehicle Condition when Malfunction Detected

Fail-safe Operation when Malfunction Detected

Hybrid control system cannot be started when transmitter battery is depleted by holding electrical key transmitter sub-assembly near power switch and pressing and holding power switch with shift lever in P

-

Related Data List and Active Test

DTC No.

Data List and Active Test

B2784

-

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

  • When using the Techstream with the power switch off, connect the Techstream to the DLC3 and turn a courtesy light switch on and off at intervals of 1.5 seconds or less until communication between the Techstream and the vehicle begins. Then select the vehicle type under manual mode and enter the following menus: Body Electrical / Smart Key. While using the Techstream, periodically turn a courtesy light switch on and off at intervals of 1.5 seconds or less to maintain communication between the Techstream and the vehicle.
  • The smart key system (for Start Function, HV Model) uses the LIN communication system and CAN communication system. Inspect the communication function by following How to Proceed with Troubleshooting. Troubleshoot the smart key system (for Start Function, HV Model) after confirming that the communication systems are functioning properly.

    Click here

  • Before replacing the certification ECU (smart key ECU assembly), refer to Registration.

    Click here

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

PROCEDURE

1.

CLEAR DTC

(a) Clear the DTCs.

Body Electrical > Smart Key > Clear DTCs
NEXT

2.

CHECK FOR DTC

(a) Perform "DTC Output Confirmation Operation" procedure.

(b) Check for DTCs.

Body Electrical > Smart Key > Trouble Codes

OK:

DTC B2784 is not output.

OK

USE SIMULATION METHOD TO CHECK

NG

3.

CHECK POWER SWITCH (OUTPUT)

(a) Using an oscilloscope, check the waveform.

*a

Component with harness connected

(Power Switch)

*b

Waveform

*c

Waveform (detail)

-

-

OK:

Tester Connection

Condition

Tool Setting

Specified Condition

G117-8 (CODE) - G117-6 (AGND)

Power switch off, power switch pressed with electrical key transmitter sub-assembly held near power switch*

1 V/DIV., 20 ms./DIV.

Pulse generation

(See waveform)

2 V/DIV., 100 μs./DIV.

Pulse generation

(See waveform (detail))

  • *: Remove the transmitter battery before performing this inspection.

OK:

The waveform is similar to that shown in the illustration.

OK

REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

NG

REPLACE POWER SWITCH

    Power Source Control ECU Malfunction (B2782)

    IG2 Signal Malfunction (B2788)

    See More:

    Toyota Avalon Service & Repair Manual > Smart Key System(for Entry Function, Gasoline Model): Driver Side Door Entry Lock and Unlock Functions do not Operate
    DESCRIPTION If the entry lock and unlock functions do not operate for the driver door only, the request code may not be being transmitted from the driver door or the front door outside handle assembly (for driver door) (touch sensor) may be malfunctioning. If the entry functions for other doors oper ...

    Toyota Avalon Owners Manual

    Toyota Avalon Service & Repair Manual

    © 2024 Copyright www.tavalon.net
    0.0163