Toyota Yaris: Lin Communication System / Power Source Control System Missing Message (B278C87)

Toyota Yaris XP210 (2020-2025) Reapir and Service Manual / Power Source & Network / Networking / Lin Communication System / Power Source Control System Missing Message (B278C87)

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
B278C87	Power Source Control System Missing Message	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 GTS with the ignition switch off, connect the GTS to the DLC3 and turn a courtesy light switch on and off at intervals of 1.5 seconds or less until communication between the GTS and the vehicle begins. Then select Model Code "KEY REGIST" under manual mode and enter the following menus: Body Electrical / Entry & Start (CAN). While using the GTS, periodically turn a courtesy light switch on and off at intervals of 1.5 seconds or less to maintain communication between the GTS and the vehicle.
Before replacing the certification ECU (smart key ECU assembly), refer to Registration.

PROCEDURE

CLEAR DTC

(a) Clear the DTCs.

Body Electrical > Smart Key > Clear DTCs

2.	CHECK FOR DTC

(a) Check for DTCs.

Body Electrical > Smart Key > Trouble Codes

Result	Proceed to
DTC 278588 is output	A
DTC 278588 is not output	B

REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

USE SIMULATION METHOD TO CHECK

ID-BOX Missing Message (B278987)

DESCRIPTION This DTC is stored when LIN communication between the certification ECU (smart key ECU assembly) and ID code box (immobiliser code ECU) stops for 10 seconds or more...

Network Gateway Ecu

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