Toyota Yaris: Smart Key System (for Start Function) / Engine Immobiliser System Incorrect Assembly (B279C95)

Toyota Yaris XP210 (2020-2026) Reapir and Service Manual / Vehicle Interior / Theft Deterrent / Keyless Entry / Smart Key System (for Start Function) / Engine Immobiliser System Incorrect Assembly (B279C95)

DESCRIPTION

If an ECM that is incompatible with the immobiliser function is installed, the ECM will store this DTC.

DTC No.	Detection Item	DTC Detection Condition	Trouble Area	Note
B279C95	Engine Immobiliser System Incorrect Assembly	An ECM that is incompatible with the immobiliser function is installed. (1-trip detection logic*)	ECM	-

*: Only detected while a malfunction is present.

Vehicle Condition and Fail-safe Function when Malfunction Detected

Vehicle Condition when Malfunction Detected	Fail-safe Function when Malfunction Detected
Engine cannot be started	-

Related Data List and Active Test

DTC No.	Data List and Active Test
B279C95	-

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 the vehicle type under manual mode and enter the following menus: Body Electrical / Smart Key. 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.
The smart key system (for Start Function) uses the LIN communication system and CAN communication system. Inspect the communication function by following How to Proceed with Troubleshooting. Troubleshoot the smart key system (for Start Function) after confirming that the communication systems are functioning properly.
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Before replacing the ECM, refer to Registration.
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After performing repairs, confirm that no DTCs are output by performing "DTC Output Confirmation Operation".

PROCEDURE

1.	REPLACE ECM

(a) Temporarily replace the ECM with a new one.

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END (ECM WAS DEFECTIVE)

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Other information:

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