Porsche 911 Manual page 61

Footbrake
Blocked pedals
WARNING
Unsuitable or improperly secured floor mats can re-
strict pedal travel or interfere with pedal operation.
The accelerator pedal may be inadvertently actuated
or the brake pedal blocked. This can result in an un-
expected increase in speed or make braking more
difficult.
e Only use floor mats that are suitable for the
vehicle.
e Secure floor mats properly and do not place them
loosely on the floor.
e Do not lay several floor mats on top of each
other.
e Ensure that the floor mats are securely fitted
again after they have been removed, such as for
cleaning.
No brake force boosting
WARNING
The brake booster is ready for operation only while
the engine is running. For this reason, much greater
force has to be applied to the pedal when braking
while the engine is switched off or if there is a defect
in the brake booster.
e Vehicles with defective brakes must not be
towed.
Water film on brake
WARNING
discs
In heavy rain, when driving through water or after
leaving a car wash, the braking action may be
delayed and increased foot pressure may be
required.
e Check the brakes after washing the vehicle.
e For this reason, keep further back from the ve-
hicle in front and "dry" the brakes by applying
them at intervals. Make sure that the traffic be-
hind you is not affected.
Reduced braking action
WARNING
After a long drive over salted or gritted roads, a
coating may form on the brake discs and pads that
significantly reduces friction and therefore the brak-
ing effect as well.
The brake discs will unavoidably start to corrode if
your vehicle is parked for an extended period. The
brakes will tend to "judder" as a result.
e If braking comfort is noticeably impaired:
Go to a qualified specialist workshop. Porsche rec-
ommends a Porsche partner as they have trained
workshop personnel and the necessary parts and
tools.
e To relieve the brake system on steep slopes, re-
member to shift to a lower gear in good time
(engine braking effect). If the engine braking ef-
fect on slopes is not sufficient, use the footbrake
at intervals. Continuous braking can cause the
brakes to overheat, impairing their effectiveness.
For information on brake fluid and checking the
brake fluid level:
> Please refer to chapter "Brake Fluid" on page 57.
> Please refer to chapter "Towing" on page 228.
Brake pads and brake discs
Wear on the brake pads and brake discs depends to
a great extent on the driving style and the conditions
of use and therefore cannot be expressed in actual
miles on the road.
The high performance brake system is designed to
ensure the best possible braking effect at all speeds
and temperatures.
Certain speeds, braking forces and ambient condi-
tions (e.g. temperature and humidity) can therefore
cause the brakes to squeal.
Responding to warning message
If the wear limit of the brake pads is reached, a
warning symbol is displayed.
> Please refer to chapter "Warning and Information
Messages" on page 255.
e Have brake pads replaced immediately.
Visit a qualified specialist workshop. Porsche
recommends a Porsche partner as they have
trained workshop personnel and the necessary
parts and tools.
Porsche Ceramic Composite Brake (PCCB)
The high performance brake system is designed to
ensure the best possible braking effect at all speeds
and temperatures.
Certain speeds, braking forces and ambient condi-
tions (e.g. temperature and humidity) can therefore
cause the brakes to squeal.
Wear on different components of the brake system,
e.g. brake pads or brake discs, depends to a great
extent on the individual driving style and the condi-
tions of use and therefore cannot be expressed in
actual miles on the road.
The values communicated by Porsche are based on
normal operation adapted to the traffic situation.
Wear increases considerably when the vehicle is
driven on race tracks or as a result of aggressive
driving.
Brakes
A
B
C
D
E
F
G
H
I
J
K
L
M
N
O
P
Q
R
S
T
U
V
W
X
Y
Z
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