Toyota Tacoma (2015-2018) Service Manual: Malfunction of ID-BOX Recognition (B278D)

Toyota Tacoma (2015-2018) Service Manual / Engine Immobiliser / Engine Immobiliser System(w/ Smart Key System) / Malfunction of ID-BOX Recognition (B278D)

DESCRIPTION

When the certification ECU (smart key ECU assembly) detects an input signal indicating that the vehicle is equipped with an ID code box even though the ID code box is not registered, the certification ECU (smart key ECU assembly) stores this DTC.

DTC Code	DTC Detection Condition	Trouble Area	DTC Output Confirmation Operation
B278D	One of the following conditions is met: The certification ECU (smart key ECU assembly) recognizes that the wire harness judging whether the vehicle is equipped with an ID code box or not is provided even though the ID code box is not registered. The certification ECU (smart key ECU assembly) receives a LIN signal from the ID code box even though the ID code box is not registered. The certification ECU (smart key ECU assembly) receives a LIN signal from the ID code box even though the wire harness judging whether the vehicle is equipped with an ID code box or not is not provided.	Misconnection of the ID code box	Always

*: 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
Key registration will be prohibited	-

Related Data List and Active Test

DTC Code	Data List and Active Test
B278D	-

CAUTION / NOTICE / HINT

NOTICE:

Before performing following inspection procedure, check that the ID code box (immobiliser code ECU) is not installed on the vehicle.
Before replacing the certification ECU (smart key ECU assembly), refer to Registration (See page ).
After performing repairs, perform the operation that fulfills the DTC output confirmation operation, and then confirm that no DTCs are output again.

PROCEDURE

CLEAR DTC

(a) Clear the DTCs (See page ).

2.	CHECK DTC OUTPUT

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

HINT:

Before checking for DTCs, perform the "DTC Output Confirmation Operation" procedure.

OK:

DTC B278D is not output.

END

REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

Engine Immobiliser System Signal (Some Circuit Quantity, Reported via Serial Data) Invalid (B279986)

DESCRIPTION When there are communication malfunctions between the ECM and certification ECU (smart key ECU assembly), or when the communication ID codes do not match, the ECM stores this DTC. ...

Engine Immobiliser System Circuit Short to Battery (B279A12)

DESCRIPTION When the communication line (IMI - EFIO) between the ECM and certification ECU (smart key ECU assembly) is stuck high, the ECM stores this DTC. DTC Code DTC Detec ...

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