Toyota Tacoma 2015-2018 Service Manual: Lost Communication with Power Source Control (B278C)

Toyota Tacoma 2015-2018 Service Manual / Multiplex Communication / Lin Communication System / Lost Communication with Power Source Control (B278C)

DESCRIPTION

DTC No.	DTC Detection Condition	Trouble Area
B278C	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 vehicle ignition switch off, connect the Techstream to the vehicle 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 Access. 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.
If the certification ECU (smart key ECU assembly) is replaced, register the keys (See page ).

PROCEDURE

CLEAR DTC

(a) Clear the DTCs (See page ).

2.	CHECK FOR DTC

(a) Check for DTCs (See page OK: ).

OK:

DTC B278C is not output.

USE SIMULATION METHOD TO CHECK

REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

P/W Master Switch Communication Stop (B1206)

DESCRIPTION This DTC is stored when LIN communication between the power window regulator master switch assembly and main body ECU (multiplex network body ECU) stops for 10 seconds or more. ...

Front Passenger Side Door ECU Communication Stop (B2322)

DESCRIPTION This DTC is stored when LIN communication between the front power window regulator motor assembly RH and main body ECU (multiplex network body ECU) stops for 10 seconds or more. ...

Other materials:

Replacement
REPLACEMENT CAUTION / NOTICE / HINT NOTICE: Immediately wash off any brake fluid that comes into contact with any painted surfaces. HINT: If any work is done on the brake system or if air in the brake lines is suspected, bleed the air from the system. PROCEDURE 1. FILL RESERVOIR WITH BRAK ...

System Description
SYSTEM DESCRIPTION 1. BRIEF DESCRIPTION (a) The Controller Area Network (CAN) is a serial data communication system for real time application. It is a vehicle multiplex communication system which has a high communication speed and the ability to detect malfunctions. (b) Using the CANH and C ...

Event data recorder
This vehicle is equipped with an event data recorder (EDR). The main purpose of an EDR is to record, in certain crash or near crash-like situations, such as an air bag deployment or hitting a road obstacle, data that will assist in understanding how a vehicle’s systems performed. The EDR is ...