wheel size Alfa Romeo GT 2006 Owner handbook (in English)

GETTING TO KNOW YOUR CAR
153
ed by a highly sensitive lateral acceleration
sensor.
The stabilising action of the VDC system is
based on the calculations of the system elec-
tronic control unit, which processes the sig-
nals received from the steering wheel rota-
tion sensor, acceleration sensor and rotation
speed sensor of each wheel. These signals
allow the control unit to recognise the ma-
noeuvre the driver intends to do when the
steering wheel is turned.
The control unit processes the information
received from the sensors and therefore is
able to know the position of the car instant
by instant and compares it with the course
the driver would like to follow. In the event
of a discrepancy, in a fraction of a second
the control unit chooses and commands the
most suitable intervention to bring the car
immediately back to the required course:
braking one or more wheels at different in-
tensity and, if necessary, reducing the pow-
er transmitted by the engine.
The corrective actions are modified and
controlled continuously in seeking the course
required by the driver.
The action of VDC system considerably en-
hances the active safety of the car in very
critical situations and it is particularly help-
ful when the grip conditions of the road sur-
face change.For the VDC system to
work correctly, the tyres
must be of the same brand
and type on all wheels, in perfect
conditions and above all of the
specified type, brand and size.CUTTING IN
OF THE VDC SYSTEM
The cutting in of the VDC system is indi-
cated by the flashing of the
áwarning light
on the instrument cluster, to inform the dri-
ver that the car is in critical conditions of sta-
bility and grip.
VDC system
failure warning
In the event of a failure the VDC system
disengages automatically and the
áwarn-
ing light on the instrument cluster turns on
glowing steadily, together with the message
on the reconfigurable multifunction display.
In the event of an VDC system failure the
car behaves like a vehicle not fitted with this
system: in any case it is advisable to con-
tact Alfa Romeo Authorised Services as soon
as possible.During use of the compact
spare wheel, the VDC sys-
tem continues working. It
should be borne in mind that the
spare wheel is smaller than a nor-
mal tyre, therefore its grip is low-
er than that of the other tyres of
the car.

GETTING TO KNOW YOUR CAR
155
ASR system
failure warning
In the event of a fault, the ASR system
switches off automatically and the
Vwarn-
ing light on the instrument cluster turns on,
together with the message on the reconfig-
urable multifunction display.
In the event of an ASR system operating
failure, the car behaves in the same way
as a car that is not fitted with this system:
in any case, it is advisable to contact Alfa
Romeo Authorised Services as soon as pos-
sible.
MSR SYSTEM
(Engine drive adjustment)
The car is fitted with a special system, in-
tegral with the ASR system, that in case of
sudden gear shifting, cuts in providing torque
to the engine thus preventing excessive dri-
ving wheel drive that, specially in poor grip
conditions, can lead to loss of stability.
EOBD SYSTEM
The EOBD system (European On Board Di-
agnosis) allows continuous diagnosis of the
components of the car correlated with emis-
sions.
It also alerts the driver, by turning on the
warning light
Uon the instrument panel
(on some versions together with the mes-
sage + symbol on the reconfigurable multi-
function display) (see section “Warning
lights and messages”), when these condi-
tions are no longer in peak conditions.
The objective is:
– to keep the system efficiency under con-
trol;
– to warn when a fault causes emission
levels to increase;
– to warn of the need to replace deterio-
rated components.
The system also has a diagnostic connec-
tor that can be interfaced with appropriate
tools, which makes it possible to read the
error codes stored in the control unit, to-
gether with a series of specific parameters
for engine operation and diagnosis. This
check can also be carried out by the traffic
police. During use of the compact
spare wheel, the ASR func-
tion is cut off and the
V
warning light on the instrument
cluster turns on glowing steadily
together with the message on the
reconfigurable multifunction dis-
play.
For correct operation of
the ASR system the tyres
must absolutely be of the
same brand and type on all wheels,
in perfect conditions and, above all,
of the specified type, brand and
size.
IMPORTANTWhen travelling on snow
with snow chains, it may be helpful to turn
the ASR device off: in fact, in these condi-
tions, slipping of the driving wheels when
moving off makes it possible to obtain bet-
ter drive.

CORRECT USE OF THE CAR
208
It is necessary therefore to limit their use
to the purposes for which they are certified.
IMPORTANTWhen winter tyres are
used with a maximum speed index below
the one that can be reached by the vehicle
(increased by 5%), place a notice in the
passenger’s compartment, plainly in the dri-
ver’s view, which states the maximum per-
missible speed of the winter tyres (as per
CE Directive).
Fit the same type of tyre on all four
wheels (brand and profile) to ensure high-
er driving safety when braking and good
handling.
Remember that it is inappropriate to
change the direction of rotation of tyres. WINTER TYRES
These tyres are specially designed for dri-
ving on snow and ice, to be fitted in
replacement of those fitted on the car.
Use winter tyres of the same size as nor-
mal tyres provided on the car.
Alfa Romeo Authorised Services will be
pleased to advise you on the choice of the
tyre most suited to the use the Customer
intends to make of it.
For the type of tyre to be used, inflation
pressures and specifications of winter
tyres, follow the instructions given in the
“Technical Specifications” chapter.
The winter features of these tyres are
reduced considerably when the tread
depth is below 4 mm. In this case, they
should be replaced.
Due to the winter features, under normal
conditions of use or long motorway jour-
neys, the performance of these tyres is
lower than that of normal tyres.
SNOW CHAINS
Use of snow chains should be in compli-
ance with local regulations.
For versions 1.8 T. SPARK, 2.0
JTS and 1.9 JTD, tyre 195/60 R15 can
be fitted with snow chains (use snow chains
with reduced size with max. protrusion be-
yond the tyre profile of 12 mm), whereas
tyres 205/60 R15 - 205/55 R16 -
205/55 ZR16 - 215/45 R17 - 215/45
ZR17 - 225/40 ZR18 cannot be fitted with
snow chains.
On version 3.2
V6, tyres 215/45
R17” and 215/45 ZR 17” can only be fit-
ted with chains of the spiker spider type
whereas tyres 225/45 ZR17 - 225/40
ZR18 cannot be fitted with snow chains.
Snow chains SPIKES SPIDER COMPACT
(model 17003 compact) with 9 spikes with
16 mm adjustable length and 17 inch wheel
cap adapter are available at Lineaccessori
Alfa Romeo.
Snow chains should only be applied to
the drive wheels (front).
Before purchasing or using snow chains,
you are recommended to contact Alfa
Romeo Authorised Services.
Check the tensions of the chain after the
first few metres have been driven.

IN AN EMERGENCY
212
STARTING BY INERTIA
If the car is equipped with “Kit for tyre
repair Fix&Go“, see the instructions con-
tained in the following chapter.
GENERAL INSTRUCTIONS
As an alternative to FIX & GO, the com-
pact spare wheel or a wheel with the nor-
mal size can be supplied upon request;
wheel changing and correct use of the
jack and compact spare wheel call for
some precautions as listed below.
IN THE EVENT OF A PUNCTURE
Never push, tow or
coast start the vehicle.
This could cause fuel to
flow into the catalyst damaging
it irreversibly.
Remember that the
engine brake and power
steering are not opera-
tional until the engine is started,
therefore, much greater effort
than usual is needed on the brake
pedal and steering wheel.
Signal the presence of
the stationary vehicle
according to current regu-
lations: hazard warning lights,
reflecting triangle etc..
Any passengers should leave
the car and wait for the wheel to
be changed out of harm of the
traffic.
If parked on a slope or rough
surface, chock the wheels with
wedges or other suitable devices
to prevent the car from rolling.
Never start the engine
with the car jacked.
When driving with a
trailer, disconnect the trailer
before raising the car.
The compact spare wheel is spe-
cific to your car, do not use it on
other models, or use the spare
wheel of other models on your
vehicle.
Should the type of wheels used
be changed (alloy rims instead of
steel), it is also necessary to
change the whole set of fastening
bolts with others of suitable size.
The compact spare wheel is nar-
rower than normal wheels, it
should be used only for the dis-
tance necessary to reach a service
point to have the punctured tyre
repaired and, during its use, the
car speed must not exceed 80
km/h.