Lexus RX (RX 350L, RX450h) 2016-2025 Repair Manual: Engine Immobiliser System Incorrect Assembly (B279C95)

Lexus RX (RX 350L, RX450h) 2016-2025 Repair Manual / Vehicle Interior / Theft Deterrent / Keyless Entry / Immobiliser System / Engine Immobiliser System Incorrect Assembly (B279C95)

DESCRIPTION

If an ECM that is incompatible with the immobiliser system 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 system 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 Techstream with the engine switch off, connect the Techstream to the DLC3 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.
  • Before replacing the ECM, refer to Registration.

    Click here

  • 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.

Click here

NEXT

2.

CLEAR DTC

(a) Clear the DTCs.

Powertrain > Engine > Clear DTCs
NEXT

3.

CHECK FOR DTC

(a) Check for DTCs.

Powertrain > Engine > Trouble Codes

OK:

B279C95 is not output.

Result

Proceed to

DTC B279C95 is not output

A

DTC B279C95 is output

B
A

END (ECM WAS DEFECTIVE)
B

USE SIMULATION METHOD TO CHECK

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