Last Modified: 07-31-2024 6.11:8.1.0 Doc ID: RM100000001CY4Y
Model Year Start: 2019 Model: GR Corolla Prod Date Range: [06/2018 - 09/2022]
Title: NETWORKING: LIN COMMUNICATION SYSTEM (for Gasoline Model): B278C; Lost Communication with Power Source Control; 2019 - 2022 MY Corolla Corolla Hatchback GR Corolla [06/2018 - 09/2022]

DTC

B278C

Lost Communication with Power Source Control

DESCRIPTION

When an internal malfunction is detected in the certification ECU (smart key ECU assembly), this DTC is stored.

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

B278C

Lost Communication with Power Source Control

An internal malfunction occurs in the certification ECU (smart key ECU assembly).

Certification ECU (smart key ECU assembly)

CAUTION / NOTICE / HINT

NOTICE:

  • When using the Techstream with the engine 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 Model Code "KEY REGIST" 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.
  • Before replacing the certification ECU (smart key ECU assembly), refer to Registration.

    Click here 2019 MY Corolla Corolla Hatchback GR Corolla [06/2018 - 01/2019]; THEFT DETERRENT / KEYLESS ENTRY: SMART KEY SYSTEM (for Start Function, Gasoline Model): REGISTRATION 2020 MY Corolla Corolla Hatchback GR Corolla [01/2019 - 09/2019]; THEFT DETERRENT / KEYLESS ENTRY: SMART KEY SYSTEM (for Start Function, Gasoline Model): REGISTRATION 2020 MY Corolla Corolla Hatchback GR Corolla [09/2019 - 04/2020]; THEFT DETERRENT / KEYLESS ENTRY: SMART KEY SYSTEM (for Start Function, Gasoline Model): REGISTRATION 2021 - 2022 MY Corolla Corolla Hatchback GR Corolla [04/2020 - 09/2022]; THEFT DETERRENT / KEYLESS ENTRY: SMART KEY SYSTEM (for Start Function, Gasoline Model): REGISTRATION

PROCEDURE

1.

CLEAR DTC

(a) Clear the DTCs.

Body Electrical > Smart Key > Clear DTCs

NEXT

2.

CHECK FOR DTC

(a) Check for DTCs.

Body Electrical > Smart Key > Trouble Codes

OK:

DTC B278C is not output.

OK

USE SIMULATION METHOD TO CHECK

NG

REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) 2019 MY Corolla Corolla Hatchback Corolla HV GR Corolla [06/2018 - 01/2019]; THEFT DETERRENT / KEYLESS ENTRY: CERTIFICATION ECU: REMOVAL 2020 MY Corolla Corolla Hatchback Corolla HV GR Corolla [01/2019 - 03/2019]; THEFT DETERRENT / KEYLESS ENTRY: CERTIFICATION ECU: REMOVAL 2020 - 2022 MY Corolla Corolla Hatchback Corolla HV GR Corolla [03/2019 - 09/2022]; THEFT DETERRENT / KEYLESS ENTRY: CERTIFICATION ECU: REMOVAL