To increase protection against theft attempts, an electronic
immobilizer system known as the 'FIAT CODE' system has been adopted.All the keys are equipped with an electronic
transponder which transmits a coded signal to a special electronic
control unit in the Body Computer. This allows the engine to be started
if the code is recognised.The code used in the communication, which
takes place via aerial, changes each time the car is started up
(rolling code). The code cannot therefore be reproduced, even with
electronic scanners.The main function of the Code control unit
is to identify the code in the ignition key. The control unit contains
a secret code which is used to communicate 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 stored in the unit memory.When the key is turned ON 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 CAN and a two-way recovery serial line (W line), used
if there is a CAN failure.The Body Computer makes the information
which lights up the special CODE failure warning light in the instrument
panel through the CAN.
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Characteristic of working principle 5580E anti-theft device
.