2006 Alfa Romeo GT brake sensor

GETTING TO KNOW YOUR CAR
89
Warning
light on dialMessage
on display
d
BRAKE PAD WEAR
The warning light on the dial turns on with the brake pedal pressed (on some versions the mes-
sage + symbol are shown on the reconfigurable multifunction display) if the front brake pads are
worn; in this case have them changed as soon as possible.
IMPORTANTAs the car is fitted with wear sensors for the front brake pads, when changing
them, also check the rear brake pads.
AUTOMATIC SELESPEED TRANSMISSION FAILURE
The message and the symbol tappear on the reconfigurable multifunction display when
there is a fault in the Selespeed gearbox. Go to the nearest Alfa Romeo Authorised Service to
have the fault eliminated.

GETTING TO KNOW YOUR CAR
151
Always take due care when braking on
bends, even with the help of the ABS.
The most important advice of all, howev-
er, is this:
When the ABS cuts in, and
you feel the pulsing on the
pedal, do not lighten the
pressure, but keep the pedal firm-
ly pressed with no fear; this way
you will stop in the least space
possible, compatibly with the con-
ditions of the road surface.
Following these instructions you will be
in the best braking condition under all cir-
cumstances.
IMPORTANTCars fitted with ABS may
only be fitted with the wheel rims, tyres and
brake linings of type and brand approved by
the Manufacturer.
The system is completed by the EBD (Elec-
tronic Brake Distributor) which distributes
the braking action through the control unit
and the ABS system sensors.The car is fitted with an
electronic braking distribu-
tor (EBD). If the
>andx
warning lights turn on simultane-
ously with the engine running, this
indicates an EBD system failure; in
this case with sharp braking the
rear wheels might lock too early,
with the possibility of skidding.
Driving extremely carefully, go to
the nearest Alfa Romeo Authorised
Service to have the system
checked.
The turning on of only the
>warning light with the
engine running normally in-
dicates a fault to the ABS system
only. In this case the braking sys-
tem is still efficient, though with-
out the aid of the anti-lock device.
Under these conditions perfor-
mance of the EBD system may be
reduced. In this case too, you are
advised to go immediately to the
nearest Alfa Romeo Authorised
Service to have the system checked
over, driving in such a way as to
avoid sharp braking.
If the low brake fluid lev-
el
xwarning light turns
on, stop the car immedi-
ately and contact the nearest Alfa
Romeo Authorised Service. Any
loss of fluid from the hydraulic sys-
tem will negatively affect the op-
eration of the braking system be it
of the conventional type or of the
type with ABS.
If the compact spare wheel
is used, operation of the
ABS system is cut off and
the
>warning light on the instru-
ment cluster turns on.
IMPORTANTIf the battery is run down
the
>andxwarning lights might turn
on when starting the engine and go off af-
ter starting. This should not be considered
as a fault but as a warning that during start-
ing the ABS is not active. The turning off
of the warning lights ensures normal system
operation.

GETTING TO KNOW YOUR CAR
152
VDC SYSTEM
(Vehicle Dynamics Control)
(upon request for
versions/markets where
provided)
The VDC is an electronic system that con-
trols vehicle stability, intervening on the dri-
ving torque and braking the wheels in a dif-
ferentiated manner, in the lack of grip, it
helps to bring the car back to the correct
direction.
When travelling the car is subjected to lat-
eral and longitudinal forces which can be
controlled by the driver as long as the tyres
offer adequate roadholding; when this falls
below the minimum level, the car begins
to divert from the course required by the dri-
ver.
Especially when travelling on an uneven
surface (such as paving, or due to the pres-
ence of water, ice or soil), changes in speed
(acceleration or braking) and/or course
(bends or the need to avoid obstacles) may
cause the tyres to lose grip.When the sensors detect the conditions
that would lead to skidding, the VDC system
intervenes on the engine and on the brakes
producing a stabilising torque.
HOW THE VDC
SYSTEM WORKS
The VDC system is engaged automatical-
ly when the car is started and cannot be
switched off.
The basic components of the VDC system
are:
– an electronic control unit that process-
es the signals received from the various sen-
sors and brings about the most appropriate
strategy;
– a sensor that detects the position of the
steering wheels;
– four sensors that detect the turning
speed of each wheel;
– a sensor that detects rotation of the car
around its vertical axis;
– a sensor that detects lateral acceleration
(centrifugal force).
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, which
originates from the aeronautical industry, de-
tects the rotations of the car around its own
vertical axis. The centrifugal forces gener-
ated when the car is cornering are detect- The performance of the
system, in terms of active
safety should not induce
the driver to take pointless and un-
necessary risks. The style of dri-
ving must in any case always be
adapted to the conditions of the
road surface, visibility and traffic.
The responsibility for road safety
is always and in any case the dri-
ver’s.
The VDC system helps the driver to keep
the car under control in the event of a loss
of tyre grip.
The forces induced by the VDC system to
control the loss of vehicle stability always
depend on the grip between the tyre and
the road surface.