2011 Seat Leon 5D Owner's manual

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WARNING
● The risk of accident is higher if you drive too fast, if you do not keep
your distance to the vehicle in front, and when the road surface is slip-
pery 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! There-
fore, it is essential 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 ASR (TCS))
Anti-lock brake system (ABS)
The anti-lock brake system prevents the wheels locking dur-
ing 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
intervened. In this situation it is important to keep the brake pedal fully de-
pressed 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 re-
tained 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 233.
● If the running gear or brakes are modified, the effectiveness of the
ABS could be severely limited.

Traction control system ASR (TCS)
The traction control system prevents the drive wheels from
spinning when the vehicle is accelerating. Description and operation of the traction control system during
acceleration ASR (TCS)
ASR (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 ASR (TCS) will also stop working.
The ASR (TCS) helps the vehicle to start moving, accelerate and climb a gra-
dient in slippery conditions where this may otherwise be difficult or even
impossible. 
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184Intelligent technology
The ASR (TCS) is connected automatically when the engine starts. If neces-
sary, it may be turned on or off pushing the button on the centre console.
When the ASR (TCS) is disconnected, the warning lamp  OFF
lights up. The
TCS should normally be left on. Only in exceptional circumstances, when the
slipping of the wheels is required, should it be disconnected, for example
● 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 as soon as possible.
WARNING
● Remember that the ASR (TCS) 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 ASR (TCS)
tempt you into taking any risks when driving.
CAUTION
● To ensure that the ASR (TCS) 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, run-
ning gear or any components affecting the wheels and tyres) could affect
the efficiency of the ABS and ASR (TCS). XDS*
Driveshaft differential
When 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
that is turning faster (outer wheel) receives less drive torque than the inner
wheel. This may mean that in certain situations the torque delivered to the
inner wheel is too high, causing the wheels to spin. On the other hand, the
outer wheel is receiving a lower drive torque than it could transmit. This
causes an overall loss of lateral grip on the front axle, resulting in under-
steer or “lengthening” of the trajectory.
By using the ESC (ESP) sensors and signals, the XDS system is able to de-
tect and correct this effect.
Through the ESC (ESP), the XDS brakes the inner wheel, thereby counteract-
ing the excess drive torque in this wheel. This means that the driver's de-
sired trajectory is much more precise,
The XDS system operates in combination with the ESC (ESP) and is always
active, even when the traction control ASR (TCS) is disconnected.

Electronic Stability Control ESC (ESP) *
General notes
The Electronic Stability Control increases the vehicle's stabil-
ity on the road. The Electronic Stability Control helps reduce the danger of skidding.
The Electronic Stability Control ESC (ESP) includes the ABS, EDL, ASR (TCS)
and Steering manoeuvre recommendations. 

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Electronic Stability Control ESC (ESP)*
The ESC (ESP) reduces the danger of skidding by braking the wheels indi-
vidually.
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 vehicle. If the desired course is not being
maintained (for instance, if the vehicle is starting to skid), then the ESC
(ESP) compensates 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 ESC (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 destabilise its trajectory to the right or to the left. In this
case the ESC (ESP) recognises 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 does not steer itself with this function, the driver has full control
of the vehicle at all times.
WARNING
● Remember that ESC (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 ESC (ESP)
tempt you into taking any risks when driving.
CAUTION
● To ensure that the ESC (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, run-
ning gear or any components affecting the wheels and tyres) could affect
the efficiency of the ABS, EDL, ESC (ESP) and ASR (TCS). 
Anti-lock brake system (ABS)
The anti-lock brake system prevents the wheels locking during braking
⇒ page 183. 
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
slippery conditions where this may otherwise be difficult or even impossi-
ble.
The system will control the revolutions of the drive wheels using the ABS
sensors (in case of an EDL fault the warning lamp for ABS lights up)
⇒ page 84.
At speeds of up to approximately 80 km/h, it is able to balance out differen-
ces 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 oth-
er driven wheel via the differential. 
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To prevent the disc brake of the braking wheel from overheating, the EDL
cuts out automatically if subjected to excessive loads. The vehicle will con-
tinue to function normally without EDL. For this reason, the driver is not in-
formed that the EDL has been switched off.
The EDL will switch on again automatically when the brake has cooled
down.
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 tak-
ing 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 wheels and tyres) could affect the effi-
ciency of the EDL ⇒ page 208. 
Traction control system ASR (TCS)
The traction control system prevents the drive wheels from spinning when
the vehicle is accelerating ⇒ page 183. 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; first they must be run in. However, the reduced braking capacity may be
compensated by pressing on the brake pedal a little harder. Avoid overload-
ing 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 trips or hard driving with abrupt starts
and stops.
Wet roads or road salt
When the speed is over 80 km/h and the windscreen wipers are on, the
brake system moves the pads towards the brake discs for a few seconds.
This occurs - without the driver knowing - at regular intervals and allows a
faster response from the brakes when driving on wet roads.
In certain conditions, such as in heavy rain, or after washing the vehicle or
driving through water, the full braking effect can be delayed by moisture (or
in winter by ice) on the discs and brake pads. In this case the brakes should
be dried by pressing the brake pedal several times.
The effectiveness of the brakes can also be temporarily reduced if the vehi-
cle 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 corrosion to form on the discs and dirt to build
up on the brake pads if the vehicle is used infrequently or the brakes are
not used very often. 

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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 at 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
specialised workshop and have the fault repaired. Drive there slowly and re-
member that you will have to apply more pressure on the brake pedal and
allow for longer stopping 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 increases 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 while in neutral, when the engine is
stopped. Failure to do so could result in an accident.
CAUTION
● Never let the brakes “drag” by leaving your foot on the pedal when it is
not necessary to brake. This overheats 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 gear lever to a lower gear
position if your vehicle has automatic transmission). This makes use of en- gine 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 vehi-
cle 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 vehicle 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*)
Power steering makes it easier to turn the steering wheel
when the engine is running. Power steering assists the driver by reducing the force needed to turn the
steering wheel. In cars equipped with servotronic* power steering the de-
gree of power assistance is regulated electronically according to road
speed.
The power steering will keep on working in spite servotronic* 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 in-
stance when parking), as more effort will be required than usual. The fault
should be corrected by a specialised workshop as soon as possible.
Power steering does not work if the engine is off. In this case the steering
wheel requires much more force to turn.
If the steering is held at its turning limit when the vehicle is stationary, this
will place an excessive load on the power steering system. Turning the 
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steering wheel to its limit places a load on the system, which causes noise.
It will also reduce the idling speed of the engine.
CAUTION
When the engine is running, do not turn 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 vehicle 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 vehicle to a
specialised workshop as soon as possible.
● The power steering system requires a special hydraulic fluid. The con-
tainer is located in the engine compartment (front left). The correct fluid lev-
el in the reservoir is important for the power steering to function properly.
The hydraulic fluid level is checked at the Inspection Service. 

189
Driving and the environment
Driving and the environment
Running-in Running in a new engine
The engine needs to be run in over the first 1500 km.
Up to 1000 kilometres
– Do not drive at speeds of more than 2/3 the maximum speed.
– Do not accelerate hard.
– Avoid high engine revolutions.
– Do not tow a trailer.
From 1000 to 1500 kilometres
– Speeds can be gradually increased to the maximum road speed
or maximum permissible engine speed (rpm).
During its first few hours of running, the internal friction in the engine is
greater than later on, when all the moving parts have bedded in.
For the sake of the environment
If the engine is run in gently, its life will be increased and its oil consump-
tion reduced. Braking capacity and braking distance
The braking capacity and braking distance are influenced by
driving situations and road conditions.
The efficiency of the brakes depends directly on the
brake pad wear. The
rate of wear of the brake pads depends to a great extent on the conditions
under which the vehicle is operated and the way the vehicle is driven. If you
often drive in town traffic, drive short distances or have a sporty driving
style, we recommend that you have the thickness of your brake pads
checked by an Authorised Service Centre more frequently than recommen-
ded in the Service Plan.
If you drive with wet brakes, for example, after crossing areas of water, in
heavy rainfall or even after washing the vehicle, the effect of the brakes is
lessened as the brake discs are wet or even frozen (in winter). In this case
the brakes should be dried by pressing the brake pedal several times.
WARNING
Longer braking distances and faults in the brake system increase the risk
of accidents.
● New brake pads must be run in and do not have the correct friction
during the first 400 km. However, the reduced braking capacity may be
compensated by pressing on the brake pedal a little harder. This also ap-
plies when the brake pads have to be changed further on.
● If brakes are wet or frozen, or if you are driving on roads which have
been salted, braking power may be lower than normal. 
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190Driving and the environment
WARNING (Continued)
● On steep slopes, if brakes are excessively used, they will overheat.
Before driving down a long steep slope, it is advisable to reduce speed
and change down into a lower gear or range (depending on the type of
transmission). This makes use of engine braking and relieves the brakes.
● Never let the brakes “drag” by applying light pressure. Continuous
braking will cause the brakes to overheat and the braking distance will
increase. Apply and then release the brakes alternately.
● Never let the vehicle run with the engine switched off. The braking
distance is increased considerably when the brake servo is not active.
● If the brake fluid loses its viscosity and is subjected to heavy use, va-
pour bubbles can form in the brake system. This reduces the efficiency of
the brakes.
● Non-standard or damaged front spoilers could restrict the airflow to
the brakes and cause them to overheat. Before purchasing accessories
please observe the relevant instructions ⇒ page 208, Technical modifi-
cations.
● If a brake circuit fails, the braking distance will be increased consider-
ably. Contact a specialised workshop immediately and avoid unnecessa-
ry journeys.

Exhaust gas purification system Catalytic converter*
To maintain the useful life of the catalytic converter
– Use only unleaded petrol with petrol engines, as lead damages
the catalytic converter.
– Do not let the fuel get too low in the tank. –
For engine oil changes, do not replenish with too much engine
oil ⇒ page 222, Topping up engine oil .
– Never tow the vehicle to start it, use jump leads if necessary
⇒ page 263.
If you notice misfiring, uneven running or loss of power when the vehicle is
moving, reduce speed immediately and have the vehicle inspected at the
nearest specialised workshop. In general, the exhaust gas warning lamp
will light up when any of the described symptoms occur ⇒ page 77. If this
happens, unburnt fuel can enter the exhaust system and escape into the en-
vironment. The catalytic converter can also be damaged by overheating.
WARNING
The catalytic converter reaches very high temperatures! There is a risk of
fire.
● Never park where the catalytic converter could come into contact with
dry grass or flammable materials under the vehicle.
● Do not apply additional underseal or anti-corrosion coatings to the
exhaust pipes, catalytic converter or the heat shields on the exhaust sys-
tem. These materials could catch fire when the vehicle is being driven.
CAUTION
Never run the fuel tank completely dry because the irregularity of the fuel
supply may cause ignition problems. This allows unburnt fuel to enter the
exhaust system, which could cause overheating and damage the catalytic
converter.
For the sake of the environment
Even when the emission control system is working perfectly, there may be a
smell of sulphur from the exhaust gas under some conditions. This depends
on the sulphur content of the fuel used. Quite often the problem can be
solved by changing to another brand of fuel. 