2005 Alfa Romeo 156 four wheel drive

GETTING TO KNOW YOUR CAR
142
Failures of Selespeed gearbox are signalled
to the driver through a warning light (B-fig.
126) accompanied by an acoustic signal. The gearbox can work in two operating
modes:
– the first is semiautomatic(then called
MANUAL), in which the driver directly re-
quests gearshifting through the lever on the
centre console or pressing the buttons at the
steering wheel;
– the second is automatic, calledCITY
(mode selectable with the specific button
B-fig. 124, the CITYsign appears on the
display fig. 126fitted on rev-counter), in
which the system decides directly when to
shift gear.With the gearbox in the CITYmode it is
still possible to carry out manual gearshift-
ing, both using the gear lever and the steer-
ing wheel controls. The gearbox remains in
the CITYmode.
The gear engaged (fig. 126) is always
signalled on the display regardless of the se-
lected mode.
N= neutral;
1= first gear;
2 = second gear;
3= third gear;
4= fourth gear;
5= fifth gear;
R= reverse.
fig. 126
A0B0384m

GETTING TO KNOW YOUR CAR
180
The heart of the VDC system is the VDC
control unit which with the data supplied by
the sensors installed on the car, calculates
the centrifugal forces generated when the
car is cornering. The yawing sensor detects
the rotations of the car around its own ver-
tical axis. The centrifugal forces generated
when the car is cornering are detected by
a highly sensitive lateral acceleration sensor.
The stabilising action of the VDC system is
based on calculations made by the
system’s electronic control unit which
processes the signals received from the
steering wheel rotation, lateral acceleration
and individual wheel rotation sensors. These
signals allow the control unit to recognise
the manoeuvre the driver intends to do
when turning the steering wheel.
The control unit processes the information
received from the sensors and is therefore
capable of detecting the position of the car
and comparing it with the trajectory the dri-
ver would like to follow instant by instant.
In the event of a discrepancy, the control
unit chooses and commands the most suit-
able action to bring the car back to the re-
quired course within a fraction of a second:
braking one or more wheels at a different
braking force and, if necessary it reduces the
power transmitted by the engine. The corrective actions are changed and con-
trolled continuously until the car returns to
the required course.
The action of the VDC system considerably
increases the active safety of the vehicle un-
der many critical situations and it is partic-
ularly useful also when the road surface grip
conditions change.
For the VDC, ASR and ABS
systems 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.
WARNING
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 normal tyre,
therefore its grip is lower than that
of the other tyres of the car.
WARNING
VDC SYSTEM OPERATIONThe VDC system turns on automatically
when the car is started and cannot be
switched off. It is however possible to cut
off operation of the ASR system pressing the
corresponding button on the centre console.
The main components of the VDC system
are:
– an electronic control unit which
processes the signals received from the var-
ious sensors and brings about the most ap-
propriate strategy;
– a sensor that detects the position of the
steering wheel;
– four sensors that detect the rotation
speed of each wheel;
– a sensor that detects rotation of the car
around the vertical axis;
– a sensor that detects lateral acceleration
(centrifugal force).

CORRECT USE OF THE CAR
202
It is therefore necessary to limit their use
to the purposes for which they are certified.
WARNINGWhen snow tyres are used
with a max. speed index below the one that
can be reached by the car (increased by
5%), place a notice in the passenger com-
partment, plainly in the driver’s view which
states the max. permissible speed of the
snow tyres (as per EC Directive).
All four tyres should be the same (brand
and track) to ensure greater safety when
driving and braking and better driveability.
Remember that it is inappropriate to
change the direction of rotation of tyres.
WINTER TYRESThese tyres are specially designed for dri-
ving on snow and ice, to be fitted in place
of the existing tyres.
Use snow tyres of the same size as the
normal tyres provided with the car.
Alfa Romeo Authorized Services will be
glad to provide advice concerning the most
suitable type of tyre for the customer’s re-
quirements.
For the type of tyre to be used, inflation
pressures and the specifications of snow
tyres, follow the instructions given in chap-
ter “Technical Specifications”.
The winter features of these tyres are re-
duced considerably when the tread depth
is below 4 mm. In this case, they should be
replaced. Due to the snow tyre features, un-
der normal conditions of use or on long mo-
torway journeys, the performance of these
tyres is lower than that of normal tyres.
SNOW CHAINSUse of snow chains should be in compli-
ance with local regulations.
Use snow chains with reduced size:
– for tyres 185/65 R15” e 205/60
R15” use snow chains with reduced size
with max. protrusion beyond the tyre pro-
file of 12 mm.
– for tyres 205/55 R16” use snow
chains with reduced size with max. protru-
sion beyond the tyre profile of 9 mm.
Tyres 215/45 R17” can-
not be fitted with snow
chains due to interference
with front suspension support. Snow chains should only be applied to the
driving wheels (front wheels).
Alfa Romeo Authorized Services should first
be contacted before purchasing or using
snow chains.
Check the tension of the chains after the
first few metres have been driven.
The max. speed for snow
tyres with “Q” marking is
160 km/h, 190 km/h for tyres
with “T” marking and 210 km/h
for tyres with “H” marking. The
Road Traffic Code speed limits must
however be always strictly ob-
served.
WARNING

IN AN EMERGENCY
208
The spare wheel (for ver-
sions/markets where re-
quired) is specific to your model of
car; do not use it on other models,
or use the spare wheel of other
models on your car.
Should the type of wheels used be
changed (alloy rims instead of
steel), it is also necessary to re-
place the complete kit of fastening
bolts with others of suitable size.
The compact spare wheel should
only be used in an emergency and
even then its use should be kept to
a minimum. Do not drive at speeds
of over 80 km/h.
WARNING
On the compact spare
wheel there a sticker with
the main warnings regarding the
compact spare wheel use and lim-
itations. The sticker shall never be
removed or covered. The sticker
bears the following instructions in
four languages:
ATTENTION! ONLY FOR TEMPO-
RARY USE! 80 km/h MAX! RE-
PLACE IT AS SOON AS POSSIBLE
WITH A STANDARD WHEEL. DO
NOT COVER THIS INDICATION.
No wheel cap shall be placed on
the compact spare wheel.
The car will handle differently
when the spare wheel is fitted.
Avoid sudden acceleration or brak-
ing, sharp corners and fast bends.
WARNING
The life of the spare wheel
is approx. 3,000 km. After
this distance it should be replaced
with another of the same type.
Never attempt to fit a tradition-
al tyre to a rim designed for use as
compact spare wheel. Have the
punctured wheel repaired and re-
placed as soon as possible.
Two or more compact spare
wheels should never be used to-
gether.
Do not grease the threads of the
bolts before installing them; they
might slip out.
The jack only serves for chang-
ing wheels on the car with which it
is provided or on cars of the same
model. It must not be used for oth-
er purposes such as for instance
raising cars of other models. In no
case should it be used for repairs
under the vehicle.
The vehicle may fall if the jack is
not positioned correctly.
Do not use the jack for higher ca-
pacities than stated on its label.
WARNING