2008 Seat Leon 5D brake

Driving173
Safety First
Operating instructions
Practical tips
Te c h n i c a l D a t a
•
if the clutch pedal is depressed,
•
if the vehicle is accelerated to over 180 km/h,
•
when the lever is moved to the position “CANCEL” without reaching
the “OFF” position. Once the “CANCEL” operation is completed, the lever is
released and returns to its initial position.
To resume the cruise control, release the brake or clutch pedal or reduce the
vehicle speed to less than 180 km/h and press once on the upper part of the
rocker switch RES/+ ⇒ page 172, fig. 132 .
WARNING
It is dangerous to use a set speed wh ich is too high for the current road,
traffic or weather conditions. Risk of accident.Turning off the cruise control system*
Vehicles with a manual gearbox
The system is completely turned off by moving the control all the way to
the right hand side (OFF engaged), or when the vehicle is stationary, ignition
off.
Vehicles with automatic gearbox / DSG automatic gearbox
To completely disengage the system, the selector lever must be placed in one
of the following positions: P, N , R or 1 or with the vehicle stopped and the
ignition turned off.
AB
AA
Fig. 133 Indicator and
main beam headlight
lever: switch and rocker
switch for the cruise
control
AB
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Intelligent technology175
Safety First
Operating instructions
Practical tips
Te c h n i c a l D a t a
Practical tipsIntelligent technologyBrakesBrake servoThe brake servo amplifies the pressure you apply to the brake pedal. It works
only when the engine is running .
If the brake servo is not functioning due to a malfunction, or if the vehicle has
to be towed, you will have to press the brake pedal considerably harder to
make up for the lack of servo assistance.
WARNING
The braking distance can also be affected by external factors.•
Never let the vehicle coast with the engine switched off. Failure to do so
could result in an accident. The braking distance is increased considerably
when the brake servo is not active.
•
If the brake servo is not working, for example when the vehicle is being
towed, you will have to press the brake pedal considerably harder than
normal.
Brake assist system (BAS)*
The Brake Assist System (BAS) function is only included in
vehicles with ESP.In an emergency, most drivers brake in time, but not with maximum force.
This results in unnecessarily long braking distances.
The brake assist system intervenes when you press the brake pedal very
quickly because the brake assist system registers an emergency situation. It
then very quickly builds up the full brake pressure so that the ABS can be acti-
vated more quickly and efficiently, thus reducing the braking distance.
Do not reduce the pressure on the br ake pedal. The brake assist system
switches off automatically as soon as you release the brake.
Emergency braking function
When the vehicle detects sudden braking, the hazard warning lights auto-
matically come on to warn vehicles behind. The hazard warning lights go off
when the vehicle accelerates or the hazard warning light switch is pressed.
WARNING
•
The risk of accident is higher if yo u drive too fast, if you do not keep
your distance to the vehicle in front, and when the road surface is slippery
or wet. The increased accident risk cannot be reduced by the brake assist
system.
•
The brake assist system cannot defy the laws of physics. Slippery and
wet roads are dangerous even with the brake assist system! Therefore, it is
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176essential that you adjust your speed to suit the road and traffic conditions.
Do not let the extra safety features tempt you into taking any risks when
driving.Anti-lock brake system and traction control
M-ABS (ABS and TCS)Anti-lock brake system (ABS)
The anti-lock brake system prevents the wheels locking
during braking.The anti-lock brake system (ABS) is an important part of the vehicle's active
safety system.
How the ABS works
If one of the wheels is turns too slowly in relation to the road speed, and is
close to locking, the system will reduce the braking pressure for this wheel.
The driver is made aware of this control process by a pulsating of the brake
pedal and audible noise. This is a deliberate warning to the driver that one or
more of the wheels is tending to lock and the ABS control function has inter-
vened. In this situation it is important to keep the brake pedal fully depressed
so the ABS can regulate the brake application. Do not “pump”.
If you brake hard on a slippery road surface, the best possible control is
retained as the wheels do not lock.
However, ABS will not necessarily guarantee shorter braking distances in all
conditions. The braking distance could even be longer if you brake on gravel
or on fresh snow covering a slippery surface.
WARNING
•
The anti-lock brake system cannot defy the laws of physics. Slippery
and wet roads are dangerous even with ABS! If you notice that the ABS is
working (to counteract locked wheels under braking), you should reduce
speed immediately to suit the road and traffic conditions. Do not let the
extra safety features tempt you into taking any risks when driving.
•
The effectiveness of ABS is also determined by the tyres fitted
⇒ page 222.
•
If the running gear or brakes are mo dified, the effectiveness of the ABS
could be severely limited.
Traction control system (TCS)*
The traction control system prevents the drive wheels from
spinning when the car is accelerating.Description and operation of the traction control system during acceleration
(TCS)
TCS reduces engine power to help prevent the drive wheels of front-wheel
drive vehicles losing traction during acceleration. The system works in the
entire speed range in conjunction with ABS. If a malfunction should occur in
the ABS, the TCS will also be out of action.
TCS helps the vehicle to start moving, accelerate and climb a gradient in slip-
pery conditions where this may otherwise be difficult or even impossible.
The TCS is switched on automatically when the engine is started. If necessary,
it may be turned on or off pushing the button on the centre console.
When the TCS is off, the warning lamp is lit. The TCS should normally be left
switched on at all times. Only in exceptional circumstances, when slipping of
the wheels is required, should it be disconnected for example
WARNING (continued)
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Intelligent technology177
Safety First
Operating instructions
Practical tips
Te c h n i c a l D a t a
•
With compact temporary spare wheel.
•
When using the snow chains.
•
When driving in deep snow or on soft terrain.
•
When the vehicle is bogged-down, to free it by “rocking.”
The TCS should be switched on again afterwards as soon as possible.
WARNING
•
It must be remembered that TCS cann ot defy the laws of physics. This
should be kept in mind, particular ly on slippery and wet roads and when
towing a trailer.
•
Always adapt your driving style to suit the condition of the roads and
the traffic situation. Do not let the extra safety afforded by TCS tempt you
into taking any risks when driving, this can cause accidents.Caution
•
In order to ensure that TCS function correctly, all four wheels must be
fitted with the same tyres. Any differences in the rolling radius of the tyres can
cause the system to reduce engine power when this is not desired.
•
Modifications to the vehicle (e.g. to the engine, the brake system, running
gear or any components affecting the wh eels and tyres) could affect the effi-
ciency of the ABS and TCS.
XDS*
Driveshaft differentialWhen taking a bend, the driveshaft differential mechanism allows the outer
wheel to turn at a higher speed than the inner wheel. In this way, the wheel
which is turning faster (outer wheel) receives less drive torque than the inner
wheel. This may mean that in certain situations the torque provided to the inner wheel is too high, causing the wheels to spin. On the other hand, the
outer wheel receives a lower drive torque than it could transmit. This causes
an overall loss of lateral grip on the front shaft, resulting in understeering or
“lengthening” of the path.
The XDS system is able, using the ESP sensors and signals, to detect and
correct this effect.
The XDS, via the ESP, brakes the inner wheel thus counteracting the excess
drive torque in this wheel. This means that the path requested by the driver
is more precise,
The XDS system operates in combination with the ESP and is always active,
even when the traction control, TCS, is disconnected.
Electronic stabilisation programme (ESP)*General notes
The electronic stabilisation programme increases the
vehicle's stability on the road.The electronic stabilisation programme helps to reduce the danger of skid-
ding.
The electronic stabilisation programme (ESP) consists of
ABS, EDL, TCS and
Steering manoeuvre recommendations.
Electronic Stabilising Program (ESP)*
ESP reduces the danger of skidding by braking the wheels individually.
The system uses the steering wheel angle and road speed to calculate the
changes of direction desired by the driver, and constantly compares them
with the actual behaviour of the vehi cle. If the desired course is not being
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178maintained (for instance, if the car is starting to skid), then the ESP compen-
sates automatically by braking the appropriate wheel.
The forces acting on the braked wheel bring the vehicle back to a stable
condition. If the vehicle tends to oversteer, the system will act on the front
wheel on the outside of the turn.
Steering manoeuvre recommendations
This is a complementary safety function included in the ESP This function aids
the driver to better stabilize the vehicle in a critical situation. For example, in
case of sudden braking surface with varied adherence, the vehicle will tend
to destabilize its trajectory to the right to or to the left. In this case the ESP
recognizes the situation and helps the driver with a counter steering
manoeuvre from the power steering.
This function simply provides the driver with a recommended manoeuvre in
critical situations.
The vehicle doesn't steer itself with this function, the driver has full control of
the vehicle at all times.
WARNING
•
It must be remembered that ESP cannot defy the laws of physics. This
should be kept in mind, particularly on slippery and wet roads and when
towing a trailer.
•
Always adapt your driving style to suit the condition of the roads and
the traffic situation. Do not let the extra safety afforded by ESP tempt you
into taking any risks when driv ing, this can cause accidents.Caution
•
In order to ensure that ESP functions correctly, all four wheels must be
fitted with the same tyres. Any differences in the rolling radius of the tyres can
cause the system to reduce engine power when this is not desired.
•
Modifications to the vehicle (e.g. to the engine, the brake system, running
gear or any components affecting the wheels and tyres) could affect the effi-
ciency of the ABS, EDL, ESP and TCS.
Anti-lock brake system (ABS)The anti-lock brake system prevents the wheels locking during braking
⇒ page 176.Electronic differential lock (EDL)*
The electronic differential lock helps prevent the loss of trac-
tion caused if one of the driven wheels starts spinning.EDL helps the vehicle to start moving, accelerate and climb a gradient in slip-
pery conditions where this may otherwise be difficult or even impossible.
The system will control the revolutions of the drive wheels using the ABS
sensors (in case of an EDL fault th e warning lamp for ABS lights up)
⇒ page 77.
At speeds of up to approximately 80 km/h, it is able to balance out differ-
ences in the speed of the driven wheels of approximately 100 rpm caused by
a slippery road surface on one side of the vehicle. It does this by braking the
wheel which has lost traction and distributing more driving force to the other
driven wheel via the differential.
To prevent the disc brake of the braking wheel from overheating, the EDL cuts
out automatically if subjected to excessive loads. The vehicle will continue to
function normally without EDL. For this reason, the driver is not informed that
the EDL has been switched off.
The EDL will switch on again automatically when the brake has cooled down.
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Intelligent technology179
Safety First
Operating instructions
Practical tips
Te c h n i c a l D a t a
WARNING
•
When accelerating on a slippery surface, for example on ice and snow,
press the accelerator carefully. Despite EDL, the driven wheels may start to
spin. This could impair the vehicle's stability.
•
Always adapt your driving style to suit road conditions and the traffic
situation. Do not let the extra safety afforded by EDL tempt you into taking
any risks when driving, this can cause accidents.Caution
Modifications to the vehicle (e.g. to the engine, the brake system, running
gear or any components affecting the wh eels and tyres) could affect the effi-
ciency of the EDL ⇒ page 200.The traction control system (TCS)The traction control system prevents th e drive wheels from spinning when the
car is accelerating ⇒page 176.Four-wheel drive*
On four-wheel drive models, the engine power is distributed
to all four wheelsGeneral notes
The four-wheel-drive system operates completely automatically. The propul-
sion force is distributed among the four wheels and adapted to the driving
style and the road conditions. The four-wheel drive is specially designed to complement the superior engine
power. This combination gives the car exceptional handling and performance
capabilities – both on normal roads and in more difficult conditions, such as
snow and ice.
Winter tyres
Thanks to its four-wheel drive, your car will have plenty of traction in winter
conditions, even with the standard tyres. Nevertheless, we still recommend
that winter tyres or all-season tyres sh
ould be fitted on all four wheels when
winter road conditions are expected, mainly because this will give a better
braking response.
Snow chains
On roads where snow chains are mandatory, this also applies to cars with
four-wheel drive.
Changing tyres
On vehicles with four-wheel drive, all four tyres must have the same rolling
circumference ⇒page 227.
WARNING
•
Even with four-wheel drive, you should always adjust your speed to suit
the conditions. Do not let the extra safety features tempt you into taking
any risks when driving. Failure to do so could result in an accident.
•
The braking capability of your vehicle is limited by the tyres' grip.
Vehicle behaviour is no different from a vehicle without four-wheel drive.
So do not be tempted to drive too fast on icy or slippery roads just because
the car still has good acceleration in these conditions. Failure to do so
could result in an accident.
•
On wet roads bear in mind that the front wheels may start to “aqua-
plane” and lose contact with the road if the car is driven too fast. If this
should happen, there will be no su dden increase in engine speed when
“aquaplaning” begins to warn the driver, as with a front-wheel drive car.
For this reason and for that mentio ned above, always choose a driving
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180speed suitable for the road conditions. Failure to do so could result in an
accident.Brakes
What factors can have a negative effect on the brakes?New brake pads
New brake pads do not provide optimal performance during the first 400 km
they must be “run in”. However, the reduced braking capacity may be
compensated by pressing on the brake pedal a little harder. Avoid over-
loading the brakes during run-in.
Wear
The rate of wear on the brake pads depends a great deal on how you drive and
the conditions in which the vehicle is operated. Negative factors are, for
instance, city traffic, frequent short tr ips or hard driving with abrupt starts
and stops.
Wet roads; road salt
When the velocity is over 80 km/h windscreen wipers are on, the brake
system moves the pads towards the brake discs for a few seconds. This
occurs - without warning to the driver - at regular intervals and requires a
more rapid response from the brakes when driving on wet roads.
In certain conditions, such as in heavy rain, or after washing the car or driving
through water, the full braking effect ca n be delayed by moisture (or in winter
by ice) on the discs and brake pads. The brakes should be “dried” by pressing
the pedal to restore full braking effect.
The effectiveness of the brakes can also be temporarily reduced if the car is
driven for some distance without using the brakes when there is a lot of salt on the road in winter. In this case, the layer of salt on the brake discs and pads
has to wear off before braking.
Corrosion
There may be a tendency for dirt to build up on the brake pads and corrosion
to form on the discs if the car is used infrequently, or if you only drive low
mileages without using the brakes very much.
If the brakes are not used frequently, or
if rust has formed on the disks, it is
advisable to clean off the pads and disks by braking firmly a few times from a
moderately high speed ⇒ .
Faults in the brake system
If the brake pedal travel should ever increase suddenly, this may mean that
one of the two brake circuits has failed. Drive immediately to the nearest qual-
ified workshop and have the fault rectified. On the way to the dealer, be
prepared to use more pressure on the brake pedal, and allow for longer stop-
ping distances.
Low brake fluid level
Malfunctions can occur in the brake system if the brake fluid level is too low.
The brake fluid level is monitored electronically.
Brake servo
The brake servo amplifies the pressure you apply to the brake pedal. The
brake servo works only when the engine is running.
WARNING
•
When applying the brakes to clean off deposits on the pads and discs,
select a clear, dry road. Be sure not to inconvenience or endanger other
road users. Risk of accident.
•
Ensure the vehicle does not move wh ile in neutral, when the motor is
stopped. Failure to do so could result in an accident.
WARNING (continued)
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Intelligent technology181
Safety First
Operating instructions
Practical tips
Te c h n i c a l D a t a
Caution
•
Never let the brakes “drag” by leaving your foot on the pedal when you do
not really intend to brake. This overhe ats the brakes, resulting in longer stop-
ping distances and greater wear.
•
Before driving down a long, steep gradient, it is advisable to reduce speed
and change to a lower gear (or move the selector lever to a lower gear position
if your car has automatic transmission). This makes use of engine braking
and prolongs the service life of the brakes. If you still have to use the brakes,
it is better to brake firmly at intervals than to apply the brakes continuously.Note
•
If the brake servo is not functioning due to a malfunction, or if the vehicle
has to be towed, you will have to press the brake pedal considerably harder
to make up for the lack of servo assistance.
•
If you wish to equip the car with accessories such as a front spoiler or
wheel covers, it is important that the flow of air to the front wheels is not
obstructed, otherwise the brakes can overheat.
Power steering (servotronic*)
The power steering assists the driver when turning the
steering wheel (with the engine running).The power steering assists the driver by reducing the force needed to turn the
steering wheel. In cars equipped with servotronic* power steering the degree
of power assistance is regulated electronically according to road speed.
The power steering will keep on working in spite servo tronic* device fails. The
degree of power assistance will, however, no longer adapt to different
speeds. If the electronic regulating system is not working properly, this is
most noticeable when turning the steering wheel at low speeds (for instance when parking) – more effort will be requ
ired than usual. The fault should be
corrected by a qualified work shop as soon as possible.
The power steering does not work if the engine is off. In this case the steering
wheel is very hard to turn.
If the steering is held at its turning limit when the car is stationary, this will
place an excessive load on the power steering system. Turning the steering
wheel to its limit places a load on the sy stem, which causes noise. It will also
reduce the idling speed of the engine.
Caution
When the engine is running, do not tu rn the steering wheel to its limit for
more than 15 seconds. Otherwise, there is a risk of damaging the power
steering.
Note
•
If the power steering should fail at any time or the engine is switched off
(for instance when being towed), the car can still be steered. However, more
effort will be required to turn the steering wheel.
•
If the system is leaking or malfunctioning, please take the car to a quali-
fied workshop as soon as possible.
•
The power steering requires a special hydraulic fluid. The container is
located in the engine compartment (front left). The correct fluid level in the
reservoir is important for the power steering to function properly. The
hydraulic fluid level is checked at the Inspection Service.
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