CODE DESCRIPTION

Description

To increase protection against theft attempts, an engine immobilizer system known as the CODE is used.

Each time the ignition key is turned to position S, the CODE system deactivates the engine management electronic control unit functions.

Each time the key is turned to position M, the CODE system sends the engine management control unit a recognition code to deactivate the immobilizing function.

The keys are equipped with an electronic Transponder device that sends a coded signal to a special control unit (incorporated in the Body Computer): if it recognizes the code sent, it allows the engine to be started.

The code used in the dialogue, that takes place via an aerial coaxial to the ignition switch, varies each time the engine is started (rolling code): therefore the code cannot be reproduced even using electronic scanners.

The main function of the Code control unit is to recognize the key inserted in the ignition switch: it contains the secret code used in the dialogue with the key transponder. All the codes for the enabled keys and the code used in the dialogue with the engine management control unit are contained in the unit: when the key is turned to the ON position for the first time, if the key is correctly recognized, this code is transferred to the engine management control unit which remains indelibly linked to the Code unit and therefore to the Body Computer.

The dialogue between the two units takes place via the two-way serial line.

The function also includes the display of the status by means of the CODE warning light in the instrument panel, connected via the CAN, coming on.