VESPA 633844 IT, Service Manual

Page: 75 / 308

Once the system has been programmed, master
key transponder, decoder and control unit are
strictly matched.
With this link established, it is now possible to en-
code new service keys, in the event of losses,
replacements, etc.
Each new programming deletes the previous one
so, in order to add or eliminate keys, you must re-
peat the procedure using all the keys you intend to
keep using.
If a service key should become un-coded, the ef-
ficiency of the high voltage circuit shielding must
be thoroughly inspected: In any case it is advisable
to use resistive spark plugs.
Characteristic
Shielded cap resistance
~ 5000
Ω
.
Diagnostic codes
The immobiliser system is tested each time the ig-
nition-key switch is turned from OFF to ON. During
this diagnosis phase a number of control unit sta-
tuses can be seen and various light codes dis-
played. Regardless of the code transmitted, if at
the end of the diagnosis the led remains off per-
manently, the ignition is enabled. If, however, the
led remains on permanently, it means the ignition
is inhibited:
1. Previously unused control unit - key inser-
ted : a single 2 second flash is displayed, after
which the LED remains off permanently. The keys
can be stored to memory, the vehicle can be star-
ted but with a limitation imposed on the number of
revs.
2. Previously unused control unit - transpond-
er absent or cannot be used : The LED is per-
Vespa GTV 250 i.e.
Electrical system
ELE SYS - 23