2016 Seat Leon 5D brake sensor

Driver assistance systems
speed accordingly and then controls the ad-
ju s
t
ed distance. If the vehicle detected in
front accelerates, the adaptive cruise control
will also accelerate up to the target speed
programmed at most.
The greater the speed, the greater the dis-
tance in metres should be ››› . We recom-
mend the settin g
Di

stance 3. WARNING
With regard to distance setting, the driver is
re s

ponsible for observing country-specific
legislation. Driver messages
 AC
C not available
The sy
stem 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: currently not available. No sensor vi-
sion
 ACC and Front Assist: currently not availa-
ble. 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.
Cl
e

an the sensor.
 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.
 ACC: parking brake applied
The ACC is deactivated if the parking brake is
applied. The ACC is available once again after
the parking brake is released.
 ACC: currently not available. Intervention
of stability control
The message for the driver is displayed when
the electronic stability control (ESC) inter-
venes. In this case, the ACC is automatically
switched off.
 ACC: Take action!
The message for the driver is displayed if,
when the vehicle starts up on a hill with a
mild slope, the vehicle rolls back even al-
though the ACC is activated. Apply the brake
to stop the vehicle from moving/colliding
with another vehicle.  ACC: speed limit
The mes
sage for the driver is displayed if, in
vehicles with manual gearbox, the current
speed is too low for the ACC mode.
The speed to be stored must be at least
30 km/h (18 mph). The speed limiter
switches off if the speed falls below 20 km/h
(12 mph).
 ACC: available as of the 2nd gear
The ACC is operational as of the 2nd gear
(manual gearbox).
 ACC: engine speed
The message for the driver is displayed if,
when the ACC accelerates or brakes, the driv-
er does not shift up or down a gear in time,
which means exceeding or not reaching the
permissible engine speed. The ACC switches
itself off. A buzzer warning is heard.
 ACC: clutch pressed
Vehicles with a manual gearbox: pressing the
clutch pedal for longer abandons control
mode.
Door open
Vehicles with automatic gearbox: the ACC
cannot be activated with the vehicle station-
ary and the door open.
203
Technical data
Advice
Operation
Emergencies
Safety

Driver assistance systems
Special driving situations Fig. 205
(A) Vehicle on a bend. (B) Motorcy-
c li
s
t ahead out of range of the radar sensor. Fig. 206
(C) Vehicle changing lanes. (D) One
v ehic
l

e turning and another stationary. The adaptive cruise control (ACC) has certain
ph
y
s

ical limitations inherent in the system.
For example, certain reactions of the ACC, in
certain circumstances, may be unexpected or
come late from the driver's point of view. So
pay attention in order to intervene if necessa-
ry.
For example, the following traffic situations
call for the utmost attention:
Starting driving after a stopping phase (only
vehicles with automatic gearbox)
After a stopping phase the ACC may begin
driving automatically when the vehicle in
front drives off. Overtaking
When the turn sign

al lights up before the ve-
hicle begins an overtaking manoeuvre, the
ACC accelerates the vehicle automatically
and thus reduces the distance from the vehi-
cle in front.
When the vehicle enters the overtaking lane,
if the ACC does not detect another vehicle in
front, it accelerates until it reaches the pro-
grammed speed and maintains it.
System acceleration can be interrupted at
any time by pressing the brake or moving the
third lever backwards ››› page 200.
Driving through a bend
On entering or exiting bends, the radar sen-
sor may no longer determine the vehicle in
front or react to a vehicle in the adjacent lane
››› Fig. 205 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 200.
Driving in tunnels
When driving through tunnels the radar sen-
sor may be limited. Switch off the ACC in tun-
nels. »
205
Technical data
Advice
Operation
Emergencies
Safety

Operation
Narrow or misaligned vehicles
The r a
d
ar sensor can only detect narrow or
misaligned vehicles when they are within
range ››› Fig. 205 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
Vehicles 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. 206 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. 206 D. In these ca ses, 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
operates
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 w
ith 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
time it means that there is a fault. Contact a
specialised workshop. SEAT recommends vis-
iting a SEAT dealership. WARNING
If the message ACC ready to start ap-
pear s

on the instrument panel display and
the vehicle in front starts up, the vehicle will
start up automatically. In this case the radar
sensor may not detect obstacles on the road.
This could cause an accident and serious in-
juries.
● Before driving off, check that the road is
cle
ar. If necessary, apply the brake. 206

Driver assistance systems
Front Assist system including
C ity
emer
gency braking and
pedestrian monitoring*
Introduction 

›› ›

table on page 2
The Front Assist system including City emer-
gency braking and pedestrian monitoring can
help avoid collisions.
The Front Assist system may warn the driver,
within the constraints of the system, of im-
pending collisions, prepare the vehicle for
emergency braking in case of danger, provide
support during braking and apply automatic
braking.
The City emergency braking and pedestrian
monitoring functions are an integral part of
the Front Assist system.
The Front Assist is not a replacement for
driver awareness.
Distance warning
If the system detects that safety is endan-
gered by the proximity of the vehicle in front,
it may warn the driver by means of a message
on the instrument panel when driving at a
speed of between approximately 60 km/h
(37 mph) and 250 km/h (156 mph)
››› Fig. 207. The warning moment varies depending on
the traffic
s

ituation and driver behaviour.
Advance warning
If the system detects a possible collision with
the vehicle in front, it may warn the driver by
means of an audible warning and an indica-
tion on the instrument panel when driving at
a speed of between approximately 30 km/h
(18 mph) and 250 km/h (156 mph)
››› Fig. 207.
The warning moment varies depending on
the traffic situation and driver behaviour. At
the same time, the vehicle will prepare for a
possible emergency braking ››› .
C ritic
a

l warning
If the driver fails to react to the advance
warning, the system may actively intervene in
the brakes when driving at a speed of be-
tween approximately 30 km/h (18 mph) and
250 km/h (156 mph), generating a brief jolt
to warn of the imminent collision.
Automatic braking
If the driver also fails to react to the advance
warning, the system may brake the vehicle
automatically, by progressively increasing
braking effect driving at a speed of between
approximately 4 km/h (2.5 mph) and
250 km/h (156 mph). By reducing speed in
case of a possible collision, the system may contribute to reducing the consequences of
an accident

.
Front assist
If the Front Assist notices that the driver is
not braking sufficiently in case of a collision
hazard, the system can increase braking ef-
fect and thus avert the collision when driving
at a speed of between approximately 4 km/h
(2.5 mph) and 250 km/h (156 mph). Front
assist only acts while the brake pedal is
pressed down hard. WARNING
The intelligent technology in the Front Assist
cannot c

hange the laws of physics. The driver
is always responsible for braking in time. If
the Front Assist issues a warning, then, de-
pending on the traffic circumstances, you
must brake immediately or dodge the obsta-
cle.
● 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.
● The Front Assist alone cannot avoid acci-
dents and seriou
s injuries.
● In complex driving situations, the Front As-
sis
t may issue unnecessary warnings and in-
tervene unnecessarily in braking, such as in
traffic islands.
● If the operation of the Front Assist is im-
paired, f
or example, by dirt or because the ra-
dar sensor has lost its settings, the system » 207
Technical data
Advice
Operation
Emergencies
Safety

Operation
may issue unnecessary warnings and
inter
v
ene inopportunely in the braking.
● During driving, the Front Assist does not re-
act to peop
le or animals or vehicles crossing
your path or which approach you head-on in
the same lane.
● The driver must always be ready to take
over the c
ontrol of the vehicle. Note
● When the Fr ont As

sist causes a braking,
the brake pedal is “harder”.
● Automatic interventions by the Front Assist
on the brake
s may be interrupted by pressing
the clutch, accelerator or moving the wheel.
● If the Front Assist does not work as descri-
bed in this c
hapter (e.g. in intervenes several
times unnecessarily), switch it off. Have the
system checked by a specialised workshop.
SEAT recommends visiting a SEAT dealership. On-screen warning lamps and mes-
s
ag
e

s Fig. 207
On the instrument panel display:
W arnin
g indic

ations. Distance warning
If
the s
af

e distance with regard to the vehicle
in front is exceeded, the relevant warning will
appear on the instrument panel display
. WARNING
Observe the safety warnings ›››
in Warning
and contr o
l lamps on page 109. Note
When the Front Assist is connected, the indi-
cation s

on the instrument panel screen may
be concealed by warnings from other func-
tions, such as an incoming call. Radar sensor
Fig. 208
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. 208 1 . This sensor can detect vehi-
c l
e

s in front up to a distance of approximately
120 m.
The radar 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
Front Assist monitoring system does not
work. The instrument panel displays the fol-
lowing message: Front Assist: No sensor vision! If necessary clean the ra-
dar sensor ››› .
When the r a
d

ar sensor begins to operate
properly again, the Front Assist will automati-
cally be available again. The message will
disappear from the instrument panel display.
208

Operation
Depending on the infotainment system in-
s t
al
led in the vehicle, the advance warning
function may be adjusted as follows:
● Ready
● Medium
● Delayed
● Deactivated
SEAT r
ecommends driving with the function
in “Medium” mode.
Switching distance warning on and off
If the safe distance with regard to the vehicle
in front is exceeded, the relevant warning will
appear on the instrument panel display
. In this case, increase the safe dis-
tance.
The distance warning may be switched on
and off in the Easy Connect system using
the  button and the
S
ETUP and
Driv er a
s

sistance function buttons
› ›
›
 page 27.
The system will store the setting for the next
time the ignition is switched on.
SEAT recommends keeping the distance
warning switched on at all times. Switch Front Assist off in the following
situation

s In the following situations the Front Assist
Monitorin
g

System should be deactivated
due to the system's limitations ››› :
● When the vehicle is to be towed.
● If the vehicle is on a test bed.
● When the radar sensor is damaged.
● If the radar sensor takes a heavy knock, for
ex amp

le in a rear collision.
● If it intervenes several times unnecessarily.
● If the radar sensor is covered temporarily
with some k ind of

accessory, such as an ad-
ditional headlight or the like.
● When the vehicle is to be loaded on a lorry,
ferry
or train. WARNING
If the Front Assist is not switched off in the
sit uation

s described, serious accidents and
injuries may occur.
● Switch off the Front Assist in critical situa-
tions. System limitations
Front Assist has certain physical limitations
inher
ent in the sy

stem. Thus, in certain cir-
cumstances some of the system's reactions may be inopportune or be delayed from the
driver's s

tandpoint. So pay attention in order
to intervene if necessary.
The following conditions may cause Front As-
sist not to react or to do so too late:
● On taking tight bends.
● Pressing the accelerator all the way down.
● If the Front Assist is switched off or dam-
aged.
● If the ASR h

as been manually disconnec-
ted.
● If the E

SC is controlling.
● If several brake lights of the vehicle or elec-
trically
connected trailer are damaged.
● If the radar sensor is dirty or covered.
● If there are metal objects, e.g. rails on the
roa
d or sheets used in road works.
● If the vehicle is reversing.
● If the vehicle over-accelerates.
● In case of snow or heavy rain.
● In case of narrow vehicles, such as motor-
bike
s.
● Misaligned vehicles.
● Vehicles crossing the other's path.
● Vehicles approaching in the opposite direc-
tion.
210

Driver assistance systems
● Spec
i
al loads and accessories of other ve-
hicles that jut out over the sides, backwards
or over the top.
City Emergency braking function Fig. 210
On the instrument panel display: ad-
v anc
e w

arning message The City emergency braking function is part
of
Fr
ont

Assist and is active whenever the
system is switched on.
Depending on the equipment, the City emer-
gency braking function may be switched on
and off in the Easy Connect system using
the  button and the
S
ETUP and
Driv er a
s

sistance function buttons
› ›
›
 page 27. The City Emergency braking function picks
up, at s

peeds between approximately 4 km/h
(2.5 mph) and 30 km/h (19 mph), the traffic
situation in front of the vehicle.
If the system detects a possible collision with
a vehicle in front of it, the vehicle prepares
for a possible emergency braking ››› .
If the driv
er f

ails to react to a possible colli-
sion, the system may brake the vehicle auto-
matically, by progressively increasing braking
effect driving to reduce speed in the event of
a collision. The system can thus help to re-
duce the consequences of an accident.
Status display
Automatic deceleration by means of the City
Emergency braking function is displayed on
the instrument panel by means of the ad-
vance warning ››› Fig. 210 1)
. WARNING
The smart technology included in the City
Emerg ency

braking function cannot defy the
laws of physics. The driver is always respon-
sible for braking in time.
● 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. ●
The City Emer

gency braking function alone
cannot prevent accidents or serious injury.
● In complex driving situations, the City
Emergency
braking function may issue unnec-
essary warnings and intervene inopportunely
in braking, such as in work areas or if there
are metal rails.
● If the operation of the City Emergency brak-
ing fu
nction is impaired, for example, by dirt
or because the radar sensor has lost its set-
tings, the system may issue unnecessary
warnings and intervene inopportunely in the
braking.
● During driving, the City Emergency braking
function doe
s not react to people or animals
or vehicles crossing your path or which ap-
proach you head-on in the same lane. Note
● When the City Emer

gency braking function
causes a braking, the brake pedal is “hard-
er”.
● Automatic interventions on the brakes by
the City Emer
gency braking function may be
interrupted by pressing the clutch, accelera-
tor or moving the wheel.
● The City Emergency braking function can
brake the
vehicle until it stops completely.
However, the brake system does not halt the
vehicle permanently. Use the foot brake! »1)
The symbol on the instrument panels with colour
dis p

lay is in colour. 211
Technical data
Advice
Operation
Emergencies
Safety

Operation
●
If sev er
al inopportune intervenes occur,
switch off the Front Assist and with it the City
Emergency braking function. Take it to a spe-
cialised workshop, SEAT recommends visiting
a SEAT dealership.
● If numerous unnecessary interventions oc-
cur, the C
ity Emergency braking function may
switch off automatically. Pedestrian Monitoring*
1)Fig. 211
On the instrument panel display: 
Adv anc
e w

arning message.  Pedestrian
Monitoring deactivated. The pedestrian monitoring system can help
pr
ev
ent

accidents involving pedestrians or
reduce the consequences of an accident. The system warns of danger of collision, pre-
pare

s the vehicle for emergency braking, as-
sists in the braking and brakes automatically.
If the system detects a possible collision with
a pedestrian, it warns the driver with an
acoustic signal and a message on the dash
panel display ››› Fig. 211.
The pedestrian monitoring system, including
the advance warning, is automatically con-
nected when the ignition is switched on
››› page 167.
SEAT recommends always having the pedes-
trian monitoring system connected. The ex-
ceptions set out for the Front Assist system
are equally valid for the pedestrian monitor-
ing system ››› page 210.
Switching the pedestrian monitoring system
on and off
With the ignition on, the pedestrian monitor-
ing system can be switched on and off as fol-
lows:
● Switch the system on and off in the info-
tainment sy
stem using the  button and
the S
ETUP and
Driv
er a
s
sistance function but-
t on
s
›››
 page 27.
When the pedestrian protection system is
switched off, the dash panel display shows a message indicating this
›››
Fig. 211 . The
pedestrian monitoring system is switched off
with the Front Assist function. WARNING
The technology in the pedestrian monitoring
sys t

em cannot defy the laws of physics and
only works within the system's limits. The
driver is always responsible for braking in
time. If the pedestrian monitoring system is-
sues a warning, brake the vehicle immediate-
ly with the brake pedal or swerve to avoid the
pedestrian, depending on traffic conditions.
● The pedestrian monitoring system alone
cannot av
oid accidents or serious injury.
● In complex driving situations, the pedes-
trian monitorin
g system may issue unneces-
sary warnings and intervene unnecessarily in
braking, such as in main roads with turnings.
● If the operation of the system is impaired,
for ex
ample, because the radar sensor and
camera are covered or have lost their set-
tings, the system may issue unnecessary
warnings and intervene inopportunely in the
braking.
● The driver must always be ready to take
over the c
ontrol of the vehicle. 1)
Depending on the vehicle equipment, pedestrian
monitorin g i

s not available in all countries.
212