Last Modified: 04-05-2023 6.11:8.1.0 Doc ID: RM100000000VJL3
Model Year Start: 2016 Model: Sienna Prod Date Range: [12/2015 -           ]
Title: THEFT DETERRENT / KEYLESS ENTRY: ENGINE IMMOBILISER SYSTEM(w/o Smart Key System): B2784; Antenna Coil Open / Short; 2016 - 2020 MY Sienna [12/2015 -        ]

DTC

B2784

Antenna Coil Open / Short

DESCRIPTION

When an open or short circuit is detected in the transponder key coil, the transponder key ECU assembly stores this DTC.

DTC Code

DTC Detection Condition

Trouble Area

B2784

The transponder key coil is open or shorted.

  • Wire harness or connector
  • Transponder key coil
  • Transponder key ECU assembly

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

  • If the transponder key ECU assembly is replaced, refer to Registration (See page 2016 - 2020 MY Sienna [12/2015 -        ]; THEFT DETERRENT / KEYLESS ENTRY: ENGINE IMMOBILISER SYSTEM(w/o Smart Key System): REGISTRATION ).
  • After performing repairs, perform the operation that fulfills the DTC output confirmation operation, and then confirm that no DTCs are output again.

PROCEDURE

1.

CLEAR DTC

(a) Clear the DTCs (See page 2016 MY Sienna [12/2015 - 08/2016]; THEFT DETERRENT / KEYLESS ENTRY: ENGINE IMMOBILISER SYSTEM(w/o Smart Key System): DTC CHECK / CLEAR 2017 - 2020 MY Sienna [08/2016 -        ]; THEFT DETERRENT / KEYLESS ENTRY: ENGINE IMMOBILISER SYSTEM(w/o Smart Key System): DTC CHECK / CLEAR ).

NEXT

2.

CHECK FOR DTC

(a) Check for DTCs (See page 2016 MY Sienna [12/2015 - 08/2016]; THEFT DETERRENT / KEYLESS ENTRY: ENGINE IMMOBILISER SYSTEM(w/o Smart Key System): DTC CHECK / CLEAR 2017 - 2020 MY Sienna [08/2016 -        ]; THEFT DETERRENT / KEYLESS ENTRY: ENGINE IMMOBILISER SYSTEM(w/o Smart Key System): DTC CHECK / CLEAR ).

HINT:

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

OK:

DTC B2784 is not output.

OK

USE SIMULATION METHOD TO CHECK

(See page 2016 MY Sienna [12/2015 - 08/2016]; INTRODUCTION: HOW TO TROUBLESHOOT ECU CONTROLLED SYSTEMS: HOW TO PROCEED WITH TROUBLESHOOTING 2017 MY Sienna [08/2016 - 11/2017]; INTRODUCTION: HOW TO TROUBLESHOOT ECU CONTROLLED SYSTEMS: HOW TO PROCEED WITH TROUBLESHOOTING 2018 - 2020 MY Sienna [11/2017 -        ]; INTRODUCTION: HOW TO TROUBLESHOOT ECU CONTROLLED SYSTEMS: HOW TO PROCEED WITH TROUBLESHOOTING )

NG

3.

CHECK CONNECTION OF CONNECTOR

(a) Check that the connectors are properly connected to the transponder key coil.

NEXT

4.

CLEAR DTC

(a) Clear the DTCs (See page 2016 MY Sienna [12/2015 - 08/2016]; THEFT DETERRENT / KEYLESS ENTRY: ENGINE IMMOBILISER SYSTEM(w/o Smart Key System): DTC CHECK / CLEAR 2017 - 2020 MY Sienna [08/2016 -        ]; THEFT DETERRENT / KEYLESS ENTRY: ENGINE IMMOBILISER SYSTEM(w/o Smart Key System): DTC CHECK / CLEAR ).

NEXT

5.

CHECK FOR DTC

(a) Check for DTCs (See page 2016 MY Sienna [12/2015 - 08/2016]; THEFT DETERRENT / KEYLESS ENTRY: ENGINE IMMOBILISER SYSTEM(w/o Smart Key System): DTC CHECK / CLEAR 2017 - 2020 MY Sienna [08/2016 -        ]; THEFT DETERRENT / KEYLESS ENTRY: ENGINE IMMOBILISER SYSTEM(w/o Smart Key System): DTC CHECK / CLEAR ).

HINT:

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)

(a) Using an oscilloscope, check the waveform.

Text in Illustration

*a

Component with harness connected

(Transponder Key Coil)

*b

Waveform 1

*c

Waveform 2

-

-

Waveform 1

Item

Content

Tester Connection

D148-1 (ANT1) - Body ground

Tool Setting

20 V/DIV., 2 s./DIV.

Condition

Within 3 seconds of inserting key into ignition key cylinder

Waveform 2

Item

Content

Tester Connection

F148-5 (ANT2) - Body ground

Tool Setting

20 V/DIV., 2 s./DIV.

Condition

Within 3 seconds of inserting key into ignition key cylinder

OK:

Waveform is similar to that shown in the illustration

OK

REPLACE TRANSPONDER KEY COIL

NG

7.

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

(a) Disconnect the D151 transponder key ECU assembly connector.

(b) Disconnect the D148 transponder key coil connector.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

D151-4 (ANT1) - D148-1 (ANT1)

Always

Below 1 Ω

D151-15 (ANT2) - D148-5 (ANT2)

Always

Below 1 Ω

D151-4 (ANT1) or D148-1 (ANT1) - Body ground

Always

10 kΩ or higher

D151-15 (ANT2) or D148-5 (ANT2) - Body ground

Always

10 kΩ or higher

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

OK

8.

REPLACE TRANSPONDER KEY ECU ASSEMBLY

(a) Replace the transponder key ECU assembly with a new one (See page 2016 - 2020 MY Sienna [12/2015 -        ]; THEFT DETERRENT / KEYLESS ENTRY: TRANSPONDER KEY AMPLIFIER: REMOVAL ).

NOTICE:

Key ID code registration is necessary when replacing the transponder key ECU assembly. Refer to Registration (See page 2016 - 2020 MY Sienna [12/2015 -        ]; THEFT DETERRENT / KEYLESS ENTRY: ENGINE IMMOBILISER SYSTEM(w/o Smart Key System): REGISTRATION ).

NEXT

9.

CLEAR DTC

(a) Clear the DTCs (See page 2016 MY Sienna [12/2015 - 08/2016]; THEFT DETERRENT / KEYLESS ENTRY: ENGINE IMMOBILISER SYSTEM(w/o Smart Key System): DTC CHECK / CLEAR 2017 - 2020 MY Sienna [08/2016 -        ]; THEFT DETERRENT / KEYLESS ENTRY: ENGINE IMMOBILISER SYSTEM(w/o Smart Key System): DTC CHECK / CLEAR ).

NEXT

10.

CHECK FOR DTC

(a) Check for DTCs (See page 2016 MY Sienna [12/2015 - 08/2016]; THEFT DETERRENT / KEYLESS ENTRY: ENGINE IMMOBILISER SYSTEM(w/o Smart Key System): DTC CHECK / CLEAR 2017 - 2020 MY Sienna [08/2016 -        ]; THEFT DETERRENT / KEYLESS ENTRY: ENGINE IMMOBILISER SYSTEM(w/o Smart Key System): DTC CHECK / CLEAR ).

HINT:

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