2017 Seat Leon SC technical data

Driver assistance systems
(18 and 150 mph) and to select the distance
r equir
ed w
ith regard to the vehicle in front.
The ACC will adapt the vehicle's cruise speed
at all times, maintaining a safe distance with
the vehicle in front based on its speed.
When driving behind another vehicle, the
ACC function reduces speed until it is the
same as that of the vehicle ahead and main-
tains the set distance between the vehicles.
If the vehicle ahead accelerates, the adaptive
cruise control also accelerates, going no
higher than the target speed programmed.
If the vehicle is equipped with automatic
gearbox, the ACC can brake the vehicle until
it stops completely if a vehicle in front of it
stops.
The distance programmed should be in-
creased when the road surface is wet.
Driver intervention prompt
During driving, the ACC is subject to certain
limitations inherent in the system. In other
words, in certain circumstances the driver will
have to adjust speed him or herself, as well
as the distance from other vehicles.
In this case, the instrument panel screen will
warn you to intervene by applying the brake
and a warning tone will be heard
››› page 216. WARNING
The intelligent technology in the ACC cannot
ov er

come the system's inherent limitations
or change the laws of physics. If used negli-
gently or involuntarily, it may cause serious
accidents and injuries. The system is not a re-
placement for driver awareness.
● Adapt your speed and safe distance to the
vehicl
e in front of you at all times to suit visi-
bility, weather, road and traffic conditions.
● Do not use the ACC when visibility is bad,
on steep r
oads, with several bends or in slip-
pery circumstances such as snow, ice, rain or
loose gravel, or on flooded roads.
● Never use the ACC when driving off-road or
on unpav
ed roads. The ACC has been de-
signed for use on paved roads only.
● The ACC does not react on approaching a
fixed o
bstacle, such as the tail of a traffic
jam, a damaged vehicle or a vehicle stopped
at the traffic lights.
● The ACC only reacts to people if a pedes-
trian monitorin
g system is available. In addi-
tion, the system does not react to animals or
vehicles crossing your path or approaching
head-on down the same lane.
● If the ACC does not reduce speed sufficient-
ly, brak
e the vehicle immediately by applying
the pedal.
● If you are driving using the spare wheel,
the ACC
system could automatically switch
off during the journey. Switch off the system
when starting off. ●
If the v

ehicle continues to move involuntar-
ily after a driver intervention prompt, brake
the vehicle by applying the pedal.
● If the dash panel displays a driv
er interven-
tion prompt, adjust the distance yourself.
● The driver should be ready to accelerate or
brake b
y him/herself at all times. CAUTION
If you have the sensation that the radar sen-
sor i s d

amaged, disconnect the ACC. This will
avoid possible damage. If this occurs have it
adjusted.
● Repairs to the radar sensor require special-
ist
knowledge and special tools. SEAT recom-
mends visiting a SEAT dealership for this pur-
pose. 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 210 km/h (150 mph).
● When the A

CC is switched on, strange
noises
may be heard during automatic brak-
ing cause by the braking system. 215
Technical data
Advice
Operation
Emergencies
Safety

Driver assistance systems
Radar sensor Fig. 210
On the front bumper: radar sensor. A radar sensor is installed on the front bump-
er t
o det
ermine the tr
affic situation
››› Fig. 210 1 .
The r a
d

ar sensor's visibility may be impaired
by dirt, mud or snow, or by environmental in-
fluences such as rain or mist. In this case the
adaptive cruise control (ACC) does not work.
The instrument panel displays the following
message: ACC: No sensor vision! If
necessary, clean the sensor ››› .
When the r a
d

ar sensor begins to operate
properly again, the ACC will automatically be
available again. The message on the instru-
ment panel screen will switch off and the ACC
will be reactivated again.
ACC operation may be affected by a strong ra-
dar reverse reflection. This may occur, for ex-
ample, in a closed car park or due to the presence of metallic objects (e.g. rails on the
roa

d or sheets used in road works).
The area in front of and around the radar sen-
sor should not be covered with adhesives,
additional or similar headlights, as this may
negatively affect ACC operation.
If the front of the vehicle is not properly re-
paired or structural modifications are made
to it, for example, if the suspension is low-
ered, ACC operation may be affected. In this
scenario, SEAT recommends visiting a SEAT
dealership. CAUTION
If you have the sensation that the radar sen-
sor is d

amaged or has lost its settings, dis-
connect the ACC. This will avoid possible
damage. If this occurs have it adjusted.
● The sensor may become damaged or lose
its settin
gs when knocked, for example, dur-
ing a parking manoeuvre. This may compro-
mise the system's efficacy or disconnect it.
● Repairs to the radar sensor require special-
ist
knowledge and special tools. SEAT recom-
mends visiting a SEAT dealership for this pur-
pose.
● A registration plate or plate holder on the
front th
at is larger than the space for the reg-
istration plate, or a registration plate that is
curved or warped can cause the radar to mal-
function. ●
Cle

an away the snow with a brush and the
ice preferably with a solvent-free de-icer
spray. 217
Technical data
Advice
Operation
Emergencies
Safety

Driver assistance systems
When the ACC function is active, the vehicle
tr av
el
s at a set speed and distance from the
vehicle ahead. Both speed and distance can
be changed at any time.
Disconnecting and deactivating the ACC
To disconnect the ACC move the lever to the 0 position
›››
Fig. 211
(en
gaged). An ACC
deactivated message appears and the
function is totally deactivated.
If you do not wish to disconnect the ACC, just
to switch it temporarily to inactive mode
(Standby), move the third lever to position 3›››
Fig. 211 or pre s
s the brake pedal.
It will also switch to inactive mode (Standby)
if the vehicle is stopped and the driver door
is opened.
Adjusting the default distance level at the
start of your journey.
In wet road conditions, you should always set
a larger distance with regard to the vehicle in
front than when driving in dry conditions.
The following distances can be preselected:
● Very short
● Short
● Media
● Long
● Very long In the Easy Connect system you can adjust
the dis
t

ance level that will be applied when
the ACC is connected using the  button
and the S
ET
TINGS and
Driv
er a
s
sistance function
b utt
on
s ›››
 page 33.
Changing the driving profile
In vehicles with SEAT Drive Profile , the driving
profile selected can have an influence on the
ACC’s acceleration and braking behaviour
››› page 230.
In vehicles without SEAT Drive Profile , the be-
haviour of the ACC can also be affected by se-
lecting any of the following drive profiles in
the Easy Connect system:
● Normal
● Sport
● Eco
● Convenience
In this c
ase, you should access the ACC set-
tings using the  button and the
S
ET
TINGS >
Driv er a
s

sistance >
A
C
C function buttons
› ›
›
 page 33.
The following conditions may lead the ACC
not to react:
● If the accelerator is pressed.
● If there is no gear engaged.
● If the ESC is controlling. ●
If the driver i
s not wearing his/her seat
belt.
● If several brake lights of the vehicle or elec-
trically
connected trailer are damaged.
● If the vehicle is reversing.
● Driving faster than 210 km/h (150 mph).
Driver mes
sages
 ACC not available
The system can no longer continue to guar-
antee safe vehicle detection and will be de-
activated. The sensor has lost its setting or is
damaged. Take the vehicle to a specialised
workshop and have the fault repaired.  ACC and Front Assist: cur-
rently not available. No sensor
vision
This message will be displayed to the driver if
the radar sensor's vision is impaired due, for
example, to leaves, snow, heavy fog or dirt.
Clean the SEAT badge ››› Fig. 210.
 ACC: currently not available.
Gradient too steep
The maximum road slope has been excee-
ded, hence safe ACC operation cannot be
guaranteed. The ACC cannot be switched on.  ACC: only available in D, S
or M
Select the D/S or M position on the selector
lever. »
219Technical data
Advice
Operation
Emergencies
Safety

Driver assistance systems
Function for preventing overtaking in
an in s
ide l
aneFig. 213
On the instrument panel display:
A C
C

active, vehicle detected in an outer lane. The adaptive cruise control (ACC) has a func-
tion th
at
help

s avoid overtaking while driving
in inside lanes at certain speeds.
If another vehicle is detected travelling at a
slower speed in an outer lane, it is displayed
on the multifunction display ››› Fig. 213.
To avoid overtaking while driving in an inside
lane the system will gently brake, and in ac-
cordance with the speed will prevent the car
from overtaking. The driver can override this
function at any time. Deactivating the Adaptive Cruise Con-
trol

ACC temporarily in certain situa-
tions In the following situations the Adaptive
Crui
se C

ontrol (ACC) should be deactivated
due to the system's limitations ››› :
● When changing lanes, on tight bends and
rou nd

abouts, in acceleration and decelera-
tion lanes on motorways or in sections with
road works to prevent involuntary accelera-
tion to reach the programmed speed.
● When going through a tunnel, as operation
cou l

d be affected.
● On roads with several lanes, when other ve-
hicle
s are driving more slowly in the overtak-
ing lane. In this case, slower vehicles will be
overtaken on the right.
● In case of heavy rain, snow or spray, as the
vehicl
e in front might not be detected proper-
ly or, in certain circumstances, might not be
detected at all. WARNING
If the ACC does not switch off in the situa-
tions de

scribed, serious accidents and inju-
ries may occur.
● Always switch off the ACC in critical situa-
tions. Note
If you do not switch off the ACC in the afore-
mentioned sit uation

s, you may commit a le-
gal offence. 221
Technical data
Advice
Operation
Emergencies
Safety

Driver assistance systems
Driving through a bend
On ent erin
g or e
xiting bends, the radar sen-
sor may no longer determine the vehicle in
front or react to a vehicle in the adjacent lane
››› Fig. 214 A. In these situations the vehicle
may brake unnecessarily or fail to react to re-
act to the vehicle in front. In this case, the
driver has to intervene by accelerating or in-
terrupting the braking process by applying
the brake or pushing the third lever back-
wards ››› page 218.
Driving in tunnels
When driving through tunnels the radar sen-
sor may be limited. Switch off the ACC in tun-
nels.
Narrow or misaligned vehicles
The radar sensor can only detect narrow or
misaligned vehicles when they are within
range ››› Fig. 214 B. This applies particularly
to narrow vehicles such as motorbikes. In
these cases, you should brake as necessary.
Vehicles with special loads and accessories
Special loads and accessories of other vehi-
cles that jut out over the sides, backwards or
over the top may be out of the ACC's range.
Switch off the ACC when driving behind vehi-
cles with special loads and accessories or
when overtaking them. In these cases, you
should brake as necessary. Other vehicles changing lanes
Vehicl
es changing lanes a short distance
away from your own can only be detected
when they are within range of the sensors.
Consequently, the ACC will take longer to re-
act ››› Fig. 215 C. In these cases, you should
brake as necessary.
Stationary vehicles
The ACC does not detect stationary objects
while driving, such as traffic tails or damaged
vehicles.
If a vehicle detected by the ACC turns or
moves over and there is a stationary vehicle
in front of it, the ACC will not react to it
››› Fig. 215 D. In these cases, you should
brake as necessary.
Vehicles driving in the opposite direction
and vehicles crossing your path
The ACC does not react to vehicles approach-
ing from the opposite direction or vehicles
crossing your path.
Metal objects
Metal objects, e.g. rails on the road or sheets
used in road works, can confuse the radar
sensor and cause the ACC to react wrongly. Factors that may affect how the radar sensor
operate
s
If laser sensor operation is impaired, due to
heavy rain, spray, snow or mud, the ACC is
deactivated temporarily. The relevant text
message will appear in the dash panel dis-
play. If necessary, clean the radar sensor.
When the radar sensor begins to operate
properly again, the ACC will automatically be
available again. The message on the instru-
ment panel screen will switch off and the ACC
will be reactivated again.
ACC operation may be affected by a strong ra-
dar reverse reflection, for example in a closed
car park.
Trailer mode
When driving with trailer the ACC controls
less dynamically.
Overheated brakes
If the brakes overheat, for example after
abrupt braking or in long and steep slopes,
the ACC may be deactivated temporarily. The
relevant text message will appear in the dash
panel display. In this case, adaptive cruise
control cannot be activated.
Adaptive cruise control can be reactivated
once brake temperature has cooled suffi-
ciently. The message will disappear from the
instrument panel display. If the message ACC
not available remains on for quite a long »
223
Technical data
Advice
Operation
Emergencies
Safety

Driver assistance systems
Fig. 218
On the instrument panel display: In-
dic ation on the Lane As
s
ist system display
(example 2). Status display
The sy s
t

em is active, but not available,
either because the minimum speed has
not been reached or because the lane
lines are not recognised ››› Fig. 217 A.
The system is active and available, both
lane lines are recognised. The steering
angle is not being corrected at this mo-
ment ››› Fig. 217 B.
–
– The system is operational, the highligh-
ted line
A indicates that there was a
ri sk
of

involuntarily crossing the lane
line and that the steering is being adjus-
ted to correct the angle ››› Fig. 218 C.
The two highlighted lines A light up si-
mu lt
aneou

sly when both lane lines are
recognised and the Lane Assist function
is active ››› Fig. 218 D.
Control lamps 
It lights up yellow: Lane Assist active
but not available.
The system can not accurately recognise the lane.
Please see page 226, the Lane Assist system is not
available (the control lamp is lit up yellow). 
It lights up green
Lane Assist system active and available.
WARNING
Observe the safety warnings ›››
in Warning
and contr o
l lamps on page 119. Operating mode
Steering wheel vibration
The f
ol

lowing situations can cause vibration
in the steering wheel and require the driver
to take active control of driving: –
– ●
When the steerin
g angle assist value re-
quired to keep the vehicle in the lane is high-
er than the system’s maximum operating val-
ue.
● If the system ceases to display the lane
lines whi
le assisting with steering.
Switching the Lane Assist system on or off
Through the Easy Connect system
● Press the Easy Connect button  ●
Press the S
ET
TINGS function button
● Press the function button Driv
er a
s
sistance to
open the menu.
OR: U s
in
g the Driving Assist button on
the turn signal lever* ›››
 page 37.
Lane Assist with Lane Centring Guide
The Lane Centring Guide function is in-
tended to keep the vehicle in the centre of
the lane.
If the driver has a tendency to veer slightly off
centre in the lane, the system adapts to driv-
er preferences.
The Lane Centring Guide function is ac-
tivated/deactivated in the Easy Connect sys-
tem using the  button and the
S
ET
TINGS function button
›
››

page 120. »
225
Technical data
Advice
Operation
Emergencies
Safety

Driver assistance systems
Note
● The Lane Ass i
st system deactivates when
driving below 60 km/h (37 mph).
● The lane departure warning system has
been exc
lusively developed for driving on
paved roads only.
● If the Lane Assist system does not work as
desc
ribed in this chapter, do not use it and
contact a specialised workshop.
● Before starting a journey, verify that the
field of
vision of the camera is not covered
››› Fig. 216.
● Always keep the field of vision of the cam-
era cl
ean.
● If there is a fault in the system, have it
check
ed by a specialised workshop. Traffic Jam Assist
R el
at

ed video Fig. 219
Safety Description and operation
Traffic Jam Assist helps the driver keep the
car w
ithin its

lane and to move in convoy in
case of traffic congestion or slow traffic.
Traffic Jam Assist is an additional function of
Lane Assist ››› page 224 and combines Lane
Assist functions with Adaptive Cruise Control
(ACC) ››› page 214. Therefore, it is essential
that you read these two chapters carefully
and note the limitations of the systems and
the information about them.
Operation of Traffic Jam Assist
At speeds of below 60 km/h (40 mph), Traffic
Jam Assist can maintain a (temporary) dis-
tance preset by the driver with respect to the
vehicle ahead and help stay within the lane
››› .
T o do thi
s, the sy

stem automatically controls
the accelerator, brakes and steering, and
slows the vehicle, stopping it fully if neces-
sary, when faced with a vehicle in front that
has stopped. It automatically moves off again
when the vehicle ahead moves.
Traffic Jam Assist is designed only for use on
motorways and wide roads. Therefore, never
use it in city traffic. Technical requirements for using Traffic Jam
Assi

st
● Lane departure warning must
be activated:
 button > SETTINGS > Driver as-
sistance > Lane departure warning
(Lane Assist) › ›
›
 page 33.
● The Lane Centring Guide must be activated:
 button > SETTINGS > Driver as-
sistance > Lane departure warning
(Lane Assist)
● Adaptive Cruise Control (ACC) must be con-
nect ed and activ
e ›

›› page 218.
● The speed must be below 60 km/h
(38 mph).
Traffic

Jam Assist is not active (the Lane As-
sist control light turns yellow)
● If any of the conditions mentioned on
page 227, T
echnical requirements for using
Traffic Jam Assist are no longer met.
● If any of the conditions required for opera-
tion of the Lane Ass
ist are not met
››› page 224.
● If any of the conditions necessary for the
adaptiv
e cruise control (ACC) to work are no
longer fulfilled ››› page 214.
Situations in which Traffic Jam Assist must
be switched off
Due to the limitations of the system, Traffic
Jam Assist must always be switched off in the
following situations: »
227
Technical data
Advice
Operation
Emergencies
Safety

Driver assistance systems
If the remaining braking distance is suffi-
c ient, if
nec
essary the system slows down the
vehicle until it stops completely and auto-
matically switches on the electronic parking
brake ››› page 183.
Switching the Emergency Assist on and off
The Emergency Assist is switched on auto-
matically when the Lane Assist is switched on
››› page 224.
Technical requirements for using the Emer-
gency Assist
● The adaptive cruise control (ACC) must be
switc
hed on ››› page 214.
● The Lane Assist must be switched on
›››
page 224.
● The selector lever must be in the D/S posi-
tion or in the
Tiptronic selector gate.
● The system must have detected a lane sep-
aration line on both side
s of the vehicle
››› Fig. 218.
The following conditions may cause the
Emergency Assist not to react or to switch off
automatically:
● If the driver accelerates, brakes or moves
the steerin
g wheel.
● If any of the conditions mentioned in
›››
page 229, Technical requirements for us-
ing the Emergency Assist are not fulfilled.●
If any
of the conditions required for opera-
tion of the Lane Assist are not met
››› page 224.
● If any of the conditions necessary for the
adaptiv
e cruise control (ACC) to work are no
longer fulfilled ››› page 214. WARNING
The smart technology incorporated into the
Emerg ency

Assist cannot overcome the limits
imposed by the laws of physics; it only works
within the limits of the system. The driver is
responsible for driving the vehicle.
● Adapt your speed and safe distance to the
vehicl
e in front of you at all times to suit the
visibility, weather, road and traffic condi-
tions.
● Keep your hands on the wheel at all times
to be re
ady to intervene in the steering at any
time.
● The Emergency Assist alone cannot always
avoid acc
idents or serious injuries.
● If the operation of the Emergency Assist is
impaired, f
or example if the radar sensor of
the adaptive cruise control (ACC) or the Lane
Assist camera are covered or have lost their
settings, the system may intervene inoppor-
tunely in braking or in steering.
● The Emergency Assist does not react to
people or anim
al or vehicles crossing your
path or which approach you head-on in the
same lane. WARNING
If the Emergency Assist Intervenes inoppor-
tu nely

, serious accidents and injuries may oc-
cur.
● If the Emergency Assist does not operate
properly, sw
itch off the Lane Assist
››› page 224. Doing so will also switch off the
Emergency Assist.
● Have the system checked by a specialised
workshop
. SEAT recommends visiting a SEAT
dealership for this. Note
● Autom atic

interventions by the Emergency
Assist on the brakes may be interrupted by
pressing the accelerator or brake or by mov-
ing the wheel.
● Hazard warning lights that come on auto-
matica
lly can be switched off by pressing the
accelerator or the break, moving the steering
wheel or pressing the hazard warning light
switch.
● If this occurs, the Emergency Assist may
deceler
ate the vehicle until it comes to a com-
plete stop.
● When the Emergency Assist is activated, it
is on
ly available again after the ignition has
been switched off and back on again. 229
Technical data
Advice
Operation
Emergencies
Safety