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:

Cellular Phone Inspection
PROCEDURE 1. CHECK USAGE CONDITION (a) Check that the vehicle and cellular phone meet the following conditions: NOTICE: If changing cellular phone settings, updating software, etc. is necessary, make sure to obtain the permission of the customer before performin ...

Short to +B in Buzzer (C1ABD,C1ABE)
DESCRIPTION DTC C1ABD is stored when the blind spot monitor sensor RH detects a +B short in rear cross traffic alert buzzer (blind spot monitor buzzer) circuit. DTC C1ABE is stored when the blind spot monitor sensor RH detects a ground short or open in rear cross traffic aler ...

Engine Switch Illumination Circuit
DESCRIPTION The illuminated entry system controls the engine switch illumination. WIRING DIAGRAM PROCEDURE 1. READ VALUE USING TECHSTREAM (POWER/ENGINE SW LIGHT) (a) Connect the Techstream to the DLC3. (b) Turn the engine switch to ON. (c) Turn the Techstream ...