2015 Seat Leon 5D engine

Driver assistance systems
Brake assist system
The br ak
e a
ssist system can reduce the re-
quired braking distance. The braking force is
automatically boosted if you press the brake
pedal quickly in an emergency. You must
keep pressing the brake pedal until the dan-
ger has passed.
Traction control system (ASR)
In the event of wheelspin, the traction control
system reduces the engine torque to match
the amount of grip available. This helps the
car to start moving, accelerate or climb a gra-
dient.
Electronic differential lock (EDL)
When the EDL detects wheelspin, it brakes
the spinning wheel and directs the power to
the other driven wheel. This function is active
up to approximately 100 km/h.
To prevent the disc brake of the braked wheel
from overheating, the EDL cuts out automati-
cally if subjected to excessive loads. The ve-
hicle can still be driven. The EDL will switch
on again automatically when the brake has
cooled down.
Tractor-trailer sway mitigation*
If the vehicle is pulling a trailer, it will control
the following: Tractor-trailers tend to sway.
When the swaying of the trailer is felt by the
vehicle and detected by the ESC, it will auto- matically brake the towing vehicle within the
limits of the sy
stem and mitigate the sway.
Tractor-trailer sway mitigation is not available
in all countries.
Electronic torque management (XDS)
When taking a curve, the driveshaft differen-
tial mechanism allows the outer wheel to turn
at a higher speed than the inner wheel. In
this way, the wheel that is turning faster (out-
er 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 understeer
or “lengthening” of the trajectory.
The XDS system can detect and correct this
effect via the sensors and signals of the ESC.
Via the ESC, the XDS will brake the inside
wheel and counter the excess driving torque
of that wheel. This means that the driver's
desired trajectory is much more precise.
The XDS system works in combination with
the ESC and is always active, even when ASR
traction control is disconnected, or the ESC in
Sport mode or disconnected. Multi-collision brake
In an accident, the mu
lti-collision brake can
help the driver by braking to avoid the risk of
skidding during the accident, which could
lead to further collisions.
The multi-collision brake works for front, side
or rear accidents, when the airbag control
unit records its activation level and the acci-
dent takes place at a speed of over 10 km/h
(6 mph). The ESC automatically brakes the
vehicle, as long as the accident has not dam-
aged the ESC, the brake hydraulics or the on-
board network.
The following actions control automatic brak-
ing during the accident:
● When the driver presses the accelerator,
the automatic
braking does not take place.
● When the braking pressure through press-
ing the brak
e pedal is greater than the sys-
tem’s braking pressure the vehicle will brake
automatically.
● Multi-collision braking will not be available
if ESC
is malfunctioning. WARNING
● The ESC, ABS, ASR, EDL, el ectr

onic self-
locking differential or selective torque control
systems cannot exceed the limits imposed by
the laws of physics. Always bear this in mind, » 179
Technical data
Advice
Operation
Emergencies
Safety

Operation
especially on wet or slippery roads. If you no-
tice the sy
s
tems cutting in, you should re-
duce your speed immediately to suit the road
and traffic conditions. Do not be encouraged
to take risks by the presence of more safety
systems. If you do, an accident may occur.
● Please remember that the accident risk al-
way
s increases if you drive fast, especially in
corners or on a slippery road, or if you follow
too close behind the vehicle in front of you.
The ESC, ABS, brake assist, EDL, electronic
self-locking and selective torque control sys-
tems cannot prevent accidents: risk of acci-
dents!
● Accelerate with caution on slippery surfa-
ces
(for example, icy or snow-covered). De-
spite the control systems, the driven wheels
could spin, affecting the stability of the vehi-
cle: risk of accident! Note
● The ABS and ASR w i

ll only operate correctly
if the four wheels have identical tyres. Any
differences in the rolling radius of the tyres
can cause the system to reduce engine power
when this is not desired.
● The regulating processes of the systems
can mak
e noises when they intervene.
● If the warning lamp  lights up
, or  alter-
natively, there could be a fault ››› page 108. Switching on/off the ESC and ASR
Fig. 190
Centre console: Button for switching
on/off the E
SC

and ASR The ESC is switched on automatically when
the en
gine i
s

started, and only works when
the engine is running and includes the ABS,
EDS and ASR systems.
The ASR and ESC function should only be
switched off in situations in which traction is
insufficient, among others:
● When driving in deep snow or on surfaces
that ar
e not very firm.
● To “free” the vehicle if it gets stuck.
Then switc
h the ASR and ESC function back
on.
Depending on finishes and versions, it is
possible either to disconnect only the ASR or
else activate ESC Sport mode. ESC in “Sport” mode
Sport

mode can be connected via the Easy
Connect ››› page 110 system menu. The ac-
tion of the ESC and the ASR is limited ››› .
The c ontr
o

l lamp  lights up. For vehicles
with a driver information system*, the driver
will be shown the electronic stability
control (ESC) option: sport.
Warning! Limited stability.
Disable ESC “Sport” mode
Through the Easy Connect system menu
››› page 110. The warning lamp  will switch
off. For vehicles with a driver information sys-
tem*, the driver will be shown the elec-
tronic stability control (ESC)
option: on.
Disable ASR
The Easy Connect system is used to switch off
the ASR ››› page 110. The traction control sys-
tem will be disabled.
The control lamp  lights up. For vehicles
with a driver information system* the driver
will be informed that ASR is disabled.
Activate ASR
The Easy Connect system ››› page 110 is used
to switch on the ASR. The traction control sys-
tem will be enabled.
180

Operation
Fault in the brake system
If the br
ak
e 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 remember 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 flu-
id level is monitored electronically.
Brake servo
The brake servo increases the pressure you
apply to the brake pedal. It works only when
the engine is running. WARNING
● App ly

the brakes heavily to clean the brake
system only in a suitable traffic situation. Do
not put other road users in danger: there is
risk of causing an accident.
● Ensure the vehicle does not move while in
neutral, when the en
gine is stopped. Failure
to follow this instruction could result in an
accident.
● If the brake fluid loses its viscosity and is
subj
ected to heavy use, vapour bubbles can
form in the brake system. This reduces the ef-
ficiency of the brakes. CAUTION
● Never l et

the brakes “drag” by leaving your
foot on the pedal when it is not necessary to
brake. This overheats the brakes, resulting in
longer stopping distances and greater wear.
● Before driving down a long, steep gradient,
it is
advisable to reduce speed and select a
lower gear. This makes use of engine braking
and relieves the brakes. If you still have to
use the brakes, it is better to brake firmly at
intervals than to apply the brakes continu-
ously. Note
● If the br ak

e servo is out of action, for exam-
ple when the car is being towed, you will
have to press the brake pedal considerably
harder than normal to make up for the lack of
servo assistance.
● If you wish to equip the vehicle with acces-
sories s
uch 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. Hill driving assistant*
This function is only included in vehicles with
E
SC.
The hi l

l driving assistant helps the driver to
move off and upward on a hill when the vehi-
cle is stationary. The system maintains brake pressure for ap-
prox

imately two seconds after the driver
takes his foot off the brake pedal to prevent
the vehicle from lurching backward when it is
started. During these 2 seconds, the driver
has enough time to release the clutch pedal
and accelerate without the vehicle moving
and without having to use the handbrake,
making start-up easier, more comfortable
and safer.
These are the basic operation conditions:
● being on a ramp or hill/slope,
● doors closed,
● vehicle completely stationary,
● engine running and foot on the brake,
● besides having a gear engaged or being in
neutral f
or manual gear change and with the
selector lever at position S, D or R for an au-
tomatic gearbox.
This system is also active when reversing up-
hill. WARNING
● If y

ou do not start the vehicle immediately
after taking your foot off the brake pedal, the
vehicle may start to roll back under certain
conditions. Depress the brake pedal or use
the hand brake immediately.
● If the engine stalls, depress the brake ped-
al or u
se the hand brake immediately.182

Driver assistance systems
●
When fo l
lowing a line of traffic uphill, if you
want to prevent the vehicle from rolling back
accidentally when starting off, hold the brake
pedal down for a few seconds before starting
off. Note
The Official Service or a specialist workshop
c an t el

l you if your vehicle is equipped with
this system. Start-Stop system*
D e
s

cription and operation 

›› ›

table on page 2
The Start-Stop system helps save fuel and re-
duce CO 2 emissions.
In Start-Stop mode, the engine will automati-
cally switch off when the vehicle stops, when
stopping at traffic lights for example. The ig-
nition remains switched on during the stop-
ping phase. The engine automatically
switches back on when required.
As soon as the ignition is switched on, the
Start-Stop function is automatically activa-
ted.
Basic requirements for the Start-Stop mode ● The driver door must be closed. ●
The driver mu s

t have their seat belt fas-
tened.
● The bonnet must be closed.
● The vehicle must have travelled at more
than 4 km/h (2 mph) sinc
e the last stop.
● The vehicle cannot be towing a trailer. WARNING
● Never sw it

ch the engine off until the vehi-
cle is stationary. The brake servo and power
steering functions will not be completely cov-
ered under warranty. More force may also be
needed to turn the steering wheel or to brake.
As you cannot steer and brake in the normal
manner, there is a greater risk of accidents
and serious injury.
● Never remove the key from the ignition if
the vehic
le is in motion. Otherwise, the steer-
ing could lock making it impossible to steer
the vehicle.
● To avoid injury, make sure that the Start-
Stop sys
tem is switched off when working in
the engine compartment ››› page 185. CAUTION
The Start-Stop system must always be
swit c

hed off when driving through flooded
areas ››› page 185. Stopping/Starting the engine
Vehicles with a manual gearbox
– When the vehicle is stopped, put it into
neutral and r

elease the clutch pedal. The
engine will switch off. The warning lamp 
will appear on the instrument panel dis-
play.
– When the clutch pedal is pressed the en-
gine wil

l start up again. The warning lamp
will switch off.
Vehicles with an automatic gearbox
– Use the foot brake to bring the vehicle to a
stop and k

eep the brake pedal pressed
down with your foot. The engine will switch
off. The warning lamp  will appear in the
display.
– When you take your foot off the brake pedal
the engine wi

ll start up again. The warning
lamp will switch off.
Additional information related to the auto-
matic gearbox
The engine stops when the selector lever is in
the positions P, D, N and S, in addition to
when in manual mode. With the selector lev-
er in position P, the engine will also remain
switched off when you take your foot off the
brake pedal. In order to start the engine up
again the accelerator must be pressed, or an-
other gear engaged or the brake released. »
183
Technical data
Advice
Operation
Emergencies
Safety

Operation
If the selector lever is placed in position R
durin g the s
t
opping phase, the engine will
start up again.
Change from position D to P to prevent the
engine from accidentally starting when
changing and passing by position R. Note
● You c an c

ontrol whether the engine should
switch off or not by reducing or increasing the
brake force applied. While the vehicle re-
mains stopped, the engine will not stop if the
brake pedal is slightly pressed, in traffic jams
with frequent stopping and starting for exam-
ple. As soon as strong pressure is applied to
the brake pedal, the engine will stop.
● In vehicles with manual gearbox, during
the stop
ping phases the brake pedal must re-
main depressed to prevent the vehicle from
moving.
● If the engine “stalls” in vehicles with man-
ual g
earbox, it can be directly started up
again by immediately pressing the clutch
pedal. General notes
The system can interrupt the Start-Stop mode
fr
equently
f

or different reasons. The engine does not switch off
Befor

e the stopping phase, the system veri-
fies whether certain conditions are met. The
engine does not switch off, in the following
situations for example:
● The engine has not yet reached the mini-
mum required t
emperature for the Start-Stop
mode.
● The interior temperature selected for the air
conditioner ha
s not yet been reached.
● The interior temperature is very high/low.
● Defrost function button activated
›››
 page 45.
● The parking aid* is switched on.
● The battery is very low.
● The steering wheel is overly turned or is be-
ing turned.
● If

there is a danger of misting.
● After engaging reverse gear.
● In case of a very steep gradient.
● In the CUPRA version with automatic gear-
box, when it i
s in Tiptronic mode or in its
sports driving position ( S).
The indication  is shown on the instrument
panel display, and in addition, the driver in-
formation system* shows, . The engine starts by itself
During a s

topping phase the normal Start-
Stop mode can be interrupted in the follow-
ing situations: The engine restarts by itself
without involvement from the driver.
● The interior temperature differs from the
value select
ed on the air conditioner.
● Defrost function button activated
›››
 page 45.
● The brake has been pressed several times
consec
utively.
● The battery is too low.
● High power consumption. Note
In vehicles with an automatic gearbox, if the
select or l

ever is placed in position D, N or S
after engaging reverse gear, the vehicle must
be driven at a speed faster than 10 km/h (5
mph) for the system to return to conditions in
which the engine can be stopped. 184

Driver assistance systems
Manually switching on/off the Start-
St op sy
s
tem Fig. 191
Centre console: Start-Stop system
b utt
on If you do not wish to use the system, you can
sw
it
c

h it off manually.
– To manually switch on/off the Start-Stop
syst

em, press the button  . The button
symbo l
r
emains lit up yellow when the sys-
tem is switched off. Note
The system is automatically switched on each
time the engine i s

deliberately stopped dur-
ing a stopping phase. The engine will start
automatically. Driver messages on the instrument
p
anel
di

splay Start-Stop system deactivated.
Start the engine manually
This driv

er message is displayed when cer-
tain conditions are not met during the stop-
ping phase and the Start-Stop system cannot
restart the engine. The engine must be star-
ted manually.
Start-Stop system: Fault! Func-
tion not available There is a fault in the Start-Stop system. Take
the vehicle to a workshop to have the fault
repaired. Cruise control system (GRA)*
Operation Fig. 192
Instrument panel display: CCS status
indic ation
s Read the additional information carefully
› ›
›

 page 40
The cruise control system (CCS) is able to
maintain the set speed from 20 km/h (15
mph).
The CSS only reduces vehicle speed by ceas-
ing to accelerate, not by actively braking the
vehicle ››› .
C ontr
o

l lamp
When the warning lamp  is lit, cruise con-
trol is active. »
185
Technical data
Advice
Operation
Emergencies
Safety

Operation
Note
● If the A C
C system does not work as descri-
bed in this chapter, do not use it until it has
been checked by a specialised workshop.
SEAT recommends visiting a SEAT dealership
for this purpose.
● Maximum speed with the ACC activated is
limited to 160 km/h (100 mph).
● When the A

CC is switched on, strange
noises
may be heard during automatic brak-
ing cause by the braking system. Indications on the display, warning
and indic
ation l
amp

s Fig. 194
On the instrument panel display: (A)
A C
C

temporarily inactive, vehicle detected in
front, temporary distance adjusted. (B) ACC
active, vehicle detected in front, temporary
distance adjusted. Status display
Indic
ation
s

on the display ››› Fig. 194:
Vehicle in front, the ACC is inactive.
1 Distance margin selected, the ACC is in-
activ
e.
V ehic

le detected in front. The ACC is ac-
tive.
Adjustment of the temporary distance
from the vehicle in front with a program-
med speed.
Temporary distance adjustment from the
vehicle in front with a programmed
speed.
Warning and indication lamps
››› in Warning and indication lamps on
p ag
e 109

. 
The speed reduction by the ACC to
maintain the distance from the vehi-
cle in front is not sufficient.
Brake! apply the foot brake! Driver intervention prompt.

The ACC is not currently available.
a)
With the vehicle stationary, switch off the engine and
start it up again. Check the radar sensor visually for dirt,
ice or knocks. If it is still unavailable, refer to a special-
ised workshop to have the system inspected.
a)
The symbol on the instrument panels with colour display is in
colour.
2 3
4
5
188

Operation
●
When the traction c ontr
ol system (ASR) is
deactivated during acceleration or else the
ESC is activated in Sport* Mode
( ››› page 110), the ACC switches off automati-
cally.
● In vehicles with the Start-Stop system, the
engine swit
ches off automatically during the
ACC stopping phase and restarts automatical-
ly to begin driving. Vehicles with an automatic gearbox
If the vehicle is equipped with automatic
g
e
arbo

x, the ACC can brake the vehicle until
it stops completely if a vehicle in front of it
stops.
The ACC will still be available for a few sec-
onds. The vehicle will restart by itself if the
vehicle in front moves (traffic jam assistant).
Disconnection criteria
The ACC will switch off if the driver applies
the brake pedal or the driver's door is
opened.
If the vehicle in front remains stationary for
more than 3 seconds, the ACC will also
switch off for safety reasons. In this case the
driver should take control and apply the
brake.
In the latter case, when the ACC is switched
off with the vehicle stationary, the vehicle has to be braked by the pedal, since al-
though the car is

idling it can move, as there
is a gear engaged.
Restarting the vehicle with the ACC manually
The ACC can be activated again by moving
the lever to position 2
› ››
Fig. 198
. WARNING
Your vehicle can start up even if there is an
ob s

tacle between your vehicle and the vehi-
cle detected in front. Risk of accident! CAUTION
● If y

our vehicle with ACC does not start up
as expected, you can drive off by briefly step-
ping on the accelerator.
● The Start-Stop system usually acts if you
are drivin
g with ACC. Interrupting control
Fig. 198
On the left of the steering column:
thir d l
ev

er for operating the Adaptive Cruise
Control. Important: the ACC is active.
Int
erruptin
g c

ontrol during driving
● Move the lever to the position 3 . The
ACC
s t

andby message is displayed to the driver.
or
● Brake.
● To resume the programmed speed, turn the
lever t
o position 2 .
Int errupt
s
peed control with the vehicle sta-
tionary
Applies to vehicles with automatic gearbox:
● Move the lever to the position 3 . The
ACC
s t

andby message is displayed to the driver.
192