Last Modified: 08-21-2023 6.11:8.1.0 Doc ID: RM100000001B2OF
Model Year Start: 2019 Model: Avalon HV Prod Date Range: [04/2018 -           ]
Title: THEFT DETERRENT / KEYLESS ENTRY: SMART KEY SYSTEM (for Start Function, HV Model): B279986; Engine Immobiliser System Signal (Some Circuit Quantity, Reported via Serial Data) Invalid; 2019 - 2022 MY Avalon HV [04/2018 -        ]

DTC

B279986

Engine Immobiliser System Signal (Some Circuit Quantity, Reported via Serial Data) Invalid

DESCRIPTION

If there is a communication malfunction between the hybrid vehicle control ECUand certification ECU (smart key ECU assembly), or when the communication ID codes do not match, the hybrid vehicle control ECU stores this DTC.

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

Note

B279986

Engine Immobiliser System Signal (Some Circuit Quantity, Reported via Serial Data) Invalid

Either of the following conditions is met (1 trip detection logic*):

  • A malfunction is detected in the communication or communication lines between the hybrid vehicle control ECU and certification ECU (smart key ECU assembly).
  • The communication ID codes of the hybrid vehicle control ECU and certification ECU (smart key ECU assembly) do not match.
  • Certification ECU (smart key ECU assembly)
  • Hybrid vehicle control ECU
  • Wire harness or connector

DTC output confirmation operation (Perform either of the following):

  • Start the hybrid control system and wait for 10 seconds. If there is a malfunction, the hybrid control system will stop (communication begins within 3 seconds of the hybrid control system start operation being performed, and DTCs are stored after 6 seconds).
  • Connect the cable to the negative (-) auxiliary battery terminal, start the hybrid control system and wait for 10 seconds (communication begins within 3 seconds of the power switch being turned on (IG), and DTCs are stored after 6 seconds).
  • *: 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

-

Related Data List and Active Test

DTC No.

Data List and Active Test

B279986

-

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 2019 - 2022 MY Avalon HV [04/2018 -        ]; THEFT DETERRENT / KEYLESS ENTRY: SMART KEY SYSTEM (for Start Function, HV Model): HOW TO PROCEED WITH TROUBLESHOOTING

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

    Click here 2019 - 2020 MY Avalon HV [04/2018 - 08/2020]; THEFT DETERRENT / KEYLESS ENTRY: SMART KEY SYSTEM (for Start Function, HV Model): REGISTRATION 2021 - 2022 MY Avalon HV [08/2020 -        ]; THEFT DETERRENT / KEYLESS ENTRY: SMART KEY SYSTEM (for Start Function, HV Model): REGISTRATION

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

HINT:

When DTC B279986 and the certification ECU (smart key ECU assembly) DTC are output simultaneously, first perform troubleshooting for the certification ECU (smart key ECU assembly) DTC.

PROCEDURE

1.

REGISTER ECU COMMUNICATION ID

(a) Register the ECU communication ID code.

Click here 2019 - 2020 MY Avalon HV [04/2018 - 08/2020]; THEFT DETERRENT / KEYLESS ENTRY: SMART KEY SYSTEM (for Start Function, HV Model): REGISTRATION 2021 - 2022 MY Avalon HV [08/2020 -        ]; THEFT DETERRENT / KEYLESS ENTRY: SMART KEY SYSTEM (for Start Function, HV Model): REGISTRATION

NEXT

2.

CHECK HYBRID VEHICLE CONTROL ECU (TERMINAL IMO)

(a) Using an oscilloscope, check the waveform.

*a

Component with harness connected

(Hybrid Vehicle Control ECU)

*b

Waveform

*c

Approximately 160 ms.

*d

Approximately 270 ms.

OK:

Tester Connection

Condition

Tool Setting

Specified Condition

G47-23 (IMO) - Body ground

Within 3 seconds of hybrid control system start or within 3 seconds of power switch turned on (IG) after cable disconnected and reconnected to auxiliary battery

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

Pulse generation

(See waveform)

Result

Proceed to

Normal waveform

A

Terminal EFII stuck low (2.4 V or less)

B

Waveform not output, or has abnormal wavelength or shape

C
B

GO TO STEP 6

C

REPLACE HYBRID VEHICLE CONTROL ECU 2019 - 2021 MY Avalon HV [04/2018 - 08/2021]; HYBRID / BATTERY CONTROL: HYBRID VEHICLE CONTROL ECU: REMOVAL 2022 MY Avalon HV [08/2021 -        ]; HYBRID / BATTERY CONTROL: HYBRID VEHICLE CONTROL ECU: REMOVAL

A

3.

CHECK HYBRID VEHICLE CONTROL ECU (TERMINAL IMI)

(a) Using an oscilloscope, check the waveform.

*a

Component with harness connected

(Hybrid Vehicle Control ECU)

*b

Waveform

*c

Approximately 160 ms.

*d

Approximately 270 ms.

OK:

Tester Connection

Condition

Tool Setting

Specified Condition

G47-22 (IMI) - Body ground

Within 3 seconds of hybrid control system start or within 3 seconds of power switch turned on (IG) after cable disconnected and reconnected to auxiliary battery

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

Pulse generation

(See waveform)
NG

REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) 2019 - 2021 MY Avalon Avalon HV [04/2018 - 08/2021]; THEFT DETERRENT / KEYLESS ENTRY: CERTIFICATION ECU: REMOVAL 2022 MY Avalon Avalon HV [08/2021 -        ]; THEFT DETERRENT / KEYLESS ENTRY: CERTIFICATION ECU: REMOVAL

OK

4.

REGISTER ECU COMMUNICATION ID

(a) Register the ECU communication ID code.

Click here 2019 - 2020 MY Avalon HV [04/2018 - 08/2020]; THEFT DETERRENT / KEYLESS ENTRY: SMART KEY SYSTEM (for Start Function, HV Model): REGISTRATION 2021 - 2022 MY Avalon HV [08/2020 -        ]; THEFT DETERRENT / KEYLESS ENTRY: SMART KEY SYSTEM (for Start Function, HV Model): REGISTRATION

NEXT

5.

CHECK WHETHER HYBRID CONTROL SYSTEM STARTS

(a) Using an electrical key transmitter sub-assembly which is registered to the vehicle, turn the power switch on (IG).

(b) Check that the hybrid control system starts 5 seconds after the power switch turned on (IG).

OK:

Hybrid control system starts normally.

OK

END (ECU COMMUNICATION ID HAS NOT BEEN REGISTERED)
NG

REPLACE HYBRID VEHICLE CONTROL ECU 2019 - 2021 MY Avalon HV [04/2018 - 08/2021]; HYBRID / BATTERY CONTROL: HYBRID VEHICLE CONTROL ECU: REMOVAL 2022 MY Avalon HV [08/2021 -        ]; HYBRID / BATTERY CONTROL: HYBRID VEHICLE CONTROL ECU: REMOVAL

6.

CHECK HYBRID VEHICLE CONTROL ECU

(a) Disconnect the G47 hybrid vehicle control ECU connector.

(b) Measure the voltage according to the value(s) in the table below.

Standard Voltage:

Tester Connection

Condition

Specified Condition

G47-23 (IMO) - Body ground

Power switch turned on (IG) using registered electrical key transmitter sub-assembly

Terminal IMO stuck low (2.4 V or less)

Terminal IMO stuck high (12 V) or abnormal waveform

Result

Proceed to

Terminal IMO stuck low (2.4 V or less)

A

Terminal IMO stuck high (12 V) or abnormal waveform

B
B

REPLACE HYBRID VEHICLE CONTROL ECU 2019 - 2021 MY Avalon HV [04/2018 - 08/2021]; HYBRID / BATTERY CONTROL: HYBRID VEHICLE CONTROL ECU: REMOVAL 2022 MY Avalon HV [08/2021 -        ]; HYBRID / BATTERY CONTROL: HYBRID VEHICLE CONTROL ECU: REMOVAL

A

7.

CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - HYBRID VEHICLE CONTROL ECU)

(a) Disconnect the A10 certification ECU (smart key ECU assembly) connector.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

A10-3 (EFII) - G47-23 (IMO)

Always

Below 1 Ω

A10-3 (EFII) or G47-23 (IMO) - Other terminals and body ground

Always

10 kΩ or higher
OK

REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) 2019 - 2021 MY Avalon Avalon HV [04/2018 - 08/2021]; THEFT DETERRENT / KEYLESS ENTRY: CERTIFICATION ECU: REMOVAL 2022 MY Avalon Avalon HV [08/2021 -        ]; THEFT DETERRENT / KEYLESS ENTRY: CERTIFICATION ECU: REMOVAL

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR