brake sensor Alfa Romeo 147 2009 Owner handbook (in English)

GETTING TO KNOW YOUR CAR
80
Warning
light on dialMessage
on display
BRAKE PAD WEAR
The message + symbol are shown on the reconfigurable multifunction display when 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.
SELESPEED GEARBOX FAILURE
The message + symbol are shown by the reconfigurable multifunction display when a fault to Se-
lespeed gearbox is detected.
If warning light tand the message appear on the display, contact Al-
fa Romeo Authorised Services as soon as possible to have the fault eli-
minated.
WARNING

GETTING TO KNOW YOUR CAR
135
Always take due car when braking on
bends, even with the help of the ABS.
The most important advice of all, howev-
er, is this:
Following these instruction you will be in
the best braking condition under all circum-
stances.
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.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.
When the ABS cuts in, and
you feel the pulsing on the
pedal, do not lighten the pressure,
but keep the pedal firmly pressed
with no fear; this way you will
stop in the least space possible,
compatibly with the conditions of
the road surface.
WARNING
The car is fitted with an
electronic braking distribu-
tor (EBD). If the
>andxwarn-
ing lights turn on simultaneously
with the engine running, this indi-
cates 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 near-
est Alfa Romeo Authorised Service
to have the system checked.
WARNING
The turning on of only the
>warning light with the
engine running normally indicates a
fault to the ABS system only. In this
case the braking system is still ef-
ficient, though without the aid of
the anti-lock device. Under these
conditions performance of the EBD
system may be reduced. In this case
too, you areadvised to go immedi-
ately to the nearest Alfa Romeo
Authorised Service to have the sys-
tem checked over, driving in such
a way as to avoid sharp braking.
WARNING
If the low brake fluid lev-
el
xwarning light turns
on, stop the car immediately and
contact the nearest Alfa Romeo
Authorised Service. Any loss of
fluid from the hydraulic system
will negatively affect the opera-
tion of the braking system be it of
the conventional type or of the
type with ABS.
WARNING

GETTING TO KNOW YOUR CAR
136
VDC SYSTEM
(Vehicle Dynamics Control)
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 wheel;
– 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-
ed by a highly sensitive lateral acceleration
sensor. The VDC system helps the driver to keep
the car under control in the event of a loss
of tyre grip.
The forced induced by the VDC system to
control the loss of vehicle stability always
depend on the grip between the tyre and
the road surface.
The performance of the
system, in terms of active
safety should not induce the driver
to take pointless and unnecessary
risks. The style of driving must in
any case always be adapted to the
conditions of the road surface, vis-
ibility and traffic. The responsibil-
ity for road safety is always and
in any case the driver’s.
WARNING

TECHNICAL SPECIFICATIONS
247
SPARK PLUGS
Clean, intact spark plugs are determinant
with regard to engine efficiency and for re-
ducing the emission of pollutants.Spark plugs should be re-
placed at the intervals
specified in the Scheduled
maintenance programme. Only use
spark plugs of the specified type:
if the thermal capacity is inade-
quate or if the envisaged life is not
guaranteed inconveniences may en-
sue.
BRAKES
Service brakes: – front
– rear
Parking brake
If examined by an expert eye, the ap-
pearance of a spark plug is a sound clue
for locating a fault, even if not involving the
ignition system. Therefore if you are expe-
riencing any engine problems, it is impor-
tant to have the spark plugs checked by Al-
fa Romeo Authorized Services.
STEERING
Type
Turning radius (between pavements)
3.2 V6 24V - 3.2 V6 24V Selespeed
Disk self-ventilated
Disk
3.2 V6 24V 3.2 V6 24V Selespeed
Rack and pinion.
Hydraulic power steering with fluid reservoir in engine compartment
12.1 m 12.1 m Wheel anti-look system (ABS) with electronic braking distribution.
Servo-brake. Electronic control with brake pad wear sensors. Gaskets of ecological type.
Controlled by hand lever operating rear brakes.