2017 Seat Leon SC check engine

Operation
Indications on the display, warning
and c ontr
o
l lampsFig. 209
On the instrument panel display: (A)
A C
C

inactive (Standby). (B) ACC active. Status display
Indic
ation
s

on the display ››› Fig. 209:
Vehicle ahead detected. ACC is not active
and is not regulating your speed.
Distance from the vehicle ahead. ACC is
not active and is not regulating your dis-
tance.
1 2 Vehicle ahead detected. ACC is active and
i
s
r

egulating your speed.
Distance level 2 set by the driver.
ACC is active and is regulating your dis-
tance based on speed.
Warning and control lamps
››› in Warning and control lamps on
p ag
e 119

. 
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 SEAT badge area on the front
››› Fig. 210 (in case it is dirty or icy or it has been hit). If
it is still unavailable, refer to a specialised workshop to
have the system inspected.
a) The symbol on the instrument panels with colour display is in
colour. 
The ACC is active.
No vehicle is detected in front. The programmed speed
remains constant.3
4
5 
If the symbol is white: the ACC is ac-
tive.
A vehicle in front has been detected. The ACC adjusts
speed and distance from the vehicle in front.

If the symbol is grey: ACC is inactive
(Standby)
The system is switched on, but is not adjusting.

It lights up green
The ACC is active.
Some warning and control lamps will light up
briefly
when the ignition i
s

switched on to
check certain functions. They will switch off
after a few seconds. WARNING
Observe the safety warnings ›››
in Warning
and contr o
l lamps on page 119. Note
When the ACC is connected, the indications
on the ins trument

panel screen may be con-
cealed by warnings from other functions,
such as an incoming call. 216

Towing bracket device
Trailer towing Wh at
do
you need to bear in mind
when towing a trailer? Your vehicle may be used to tow a trailer
when fitted w
ith the c

orrect equipment.
If you wish to retrofit a towing bracket, con-
sult ››› page 254.
Connectors
Your vehicle is fitted with a 13-pin connector
for the electrical connection between the
trailer and the vehicle.
If the trailer has a 7-pin plug you will need to
use an adapter cable. It is available at any
Technical Service.
Trailer weight/drawbar load
Never exceed the authorised trailer weight. If
you do not load the trailer up to the maxi-
mum permitted trailer weight, you can then
climb correspondingly steeper slopes.
The maximum trailer weights listed are only
applicable for altitudes up to 1000 m above
sea level. With increasing altitude the engine
power and therefore the vehicle climbing
ability are impaired because of the reduced
air density. The maximum trailer weight has
to be reduced accordingly. The weight of the
vehicle and trailer combination must be re- duced by 10% for every further 1000 m (or
par
t

thereof). The gross combination weight
is the actual weight of the laden vehicle plus
the actual weight of the laden trailer. When
possible, operate the trailer with the maxi-
mum permitted drawbar load on the ball joint
of the towing bracket, but do not exceed the
specified limit.
The figures for trailer weights and drawbar
loads that are given on the data plate of the
towing bracket are for certification purposes
only. The correct towing bracket figures for
your specific model, which may be lower than
these figures, are given in the vehicle docu-
mentation or on ››› page 289, Technical
specifications.
Distributing the load
Distribute loads in the trailer so that heavy
objects are as near to the axle as possible.
Loads carried in the trailer must be secured
to prevent them moving.
Tyre pressure
The maximum permissible tyre pressure val-
ues are shown on the sticker on the back of
the left front door frame. Set the tyre pres-
sure of the trailer tyres in accordance with the
trailer manufacturer's recommendations. Exterior mirrors
Check whether
you can see enough of the
road behind the trailer with the standard rear
vision mirrors. If this is not the case, you
should have additional exterior mirrors fitted.
Both exterior mirrors should be mounted on
hinged extension brackets. Adjust the mirrors
to give sufficient vision to the rear.
Tow rope
Always use a cable between the vehicle and
the trailer ››› page 252.
Trailer rear lights
The trailer's rear lights should comply with
the statutory safety regulations ››› page 252. WARNING
Never transport people in a trailer. This could
re s

ult in fatal accidents. Note
● To w

ing a trailer places additional demands
on the vehicle. We recommend additional
services between the normal inspection inter-
vals if the vehicle is used frequently for tow-
ing a trailer.
● Find out whether special regulations apply
to to
wing a trailer in your country. 251
Technical data
Advice
Operation
Emergencies
Safety

Advice
CAUTION
● Do not u se so
lvents, wax polish, shoe
cream, stain removers, leather cleaning prod-
ucts or any similar products on Alcantara.
● To avoid damage, stubborn stains should
be remov
ed by a specialised workshop.
● On no account use brushes, hard sponges
or simil
ar utensils. Seat belts
–
Keep the seat belts clean.
– For cleaning, use a mild solution of soap
and w at
er

.
– Check the condition of the seat belts at reg-
ular int

ervals.
The retract function may not operate properly
in very dirty belts. Make sure that the inertia
reel seat belts are completely dry before al-
lowing them to retract. CAUTION
● Do not r emo

ve the seat belts from the vehi-
cle to clean them.
● Do not use chemical cleaning agents on the
seat belt
s, as this can damage the webbing.
Ensure that the seat belts do not come into
contact with corrosive fluids.
● If you find any damage to the belt webbing,
belt fitting
s, the belt retractor or the buckle, the belt in question must be replaced by a
spec
i

alised workshop. Checking and refilling levels
Fi l
lin
g the tank
Refuelling Read the additional information carefully
›› ›

 page 58
If the automatic filler nozzle is operated cor-
rectly, it will switch itself off as soon as the
fuel tank is “full”. Do not try to put in more
fuel after the nozzle cuts out, as this will fill
the expansion chamber in the fuel tank.
The correct fuel grade for your vehicle is giv-
en on a sticker on the inside of the fuel tank
flap. Further notes on fuel can be found at
››› page 266.
The capacity of your vehicle's fuel tank is giv-
en in ›››
 page 58.
Vehicles with natural gas engines and hy-
brids
Every 6 months it is necessary to run on pet-
rol until the control lamp switches off  and
then the tank must be refilled. This is neces-
sary to ensure that the system works proper-
ly, as well as the fuel quality required for driv-
ing with petrol.
264

Checking and refilling levels
WARNING
Fuel is highly flammable and can cause seri-
ous b
urns and other injuries.
● Do not smoke when filling the fuel tank or a
canis
ter. Naked flames are forbidden in the
vicinity due to the risk of explosion.
● Observe legislation governing the use,
stor
age and carrying of a spare fuel canister
in the vehicle.
● For safety reasons we do not recommend
carry
ing a spare fuel canister in the vehicle.
In an accident the canister could be damaged
and could leak.
● If, in exceptional circumstances, you have
to carr
y a spare fuel canister, please observe
the following points:
– Never fill fuel into the spare fuel canister
if it is inside or on top of the vehicle. An
electrostatic charge could build up during
filling, causing the fuel vapour to ignite.
Danger of explosion. Always place the
canister on the ground to fill it.
– Insert the filling nozzle as far as possible
into the spare fuel canister.
– If the spare fuel canister is made of met-
al, the filling nozzle must be in contact
with the canister during filling. This
helps prevent an electrostatic charge
building up. –
Never s pi

ll fuel in the vehicle or in the
luggage compartment. Fuel vapour is ex-
plosive. Risk of fatal accident! CAUTION
● If an y

fuel is spilt onto the vehicle, it
should be removed immediately. It could oth-
erwise damage the paintwork.
● Never run the tank completely dry. An irreg-
ular f
uel supply could cause misfiring. As a
result, unburnt fuel could enter the exhaust
system and damage the catalytic converter.
● When filling the fuel tank after having run it
compl
etely dry on a vehicle with a diesel en-
gine, the ignition must be switched on for at
least 30 seconds before starting the engine.
When you then start the engine it may take
longer than normal (up to one minute) to
start firing. This is because air needs to be
bled from the fuel system while starting. For the sake of the environment
Do not overfill the fuel tank, it may cause the
fuel t

o overflow if it becomes warm. Note
There is no emergency mechanism for the
manua l

release of the fuel tank flap. If neces-
sary, request assistance from specialised per-
sonnel. Note
Diesel vehicles are fitted with a protective de-
vic e th

at prevents the insertion of the wrong
fuel hose 1)
. It is only possible to refuel with
Diesel nozzles.
● If the pump nozzle is worn, damaged, or if
it is
very small, it is possible that it will not
be able to open the protective device. Before
trying to insert the pump nozzle by turning it,
try a different pump or request specialist
help.
● If you fill the tank from a reserve fuel canis-
ter, the pr
otective device will not open. One
way to resolve this is to pour the fuel in very
slowly. Refuelling with natural gas
Fig. 246
Tank flap open: gas filler mouth 1 ,
fi l
l

er mouth retainer 2 »
1)
Depending on country
265
Technical data
Advice
Operation
Emergencies
Safety

Advice
Before r efuelling, the engine and the igni-
tion, mo b
ile telephone and heating must be
switched off separately ››› .
R e
a

d the instructions on how to use the natu-
ral gas pump carefully.
The vehicle is not prepared for refuelling with
liquefied natural gas (LNG) ››› . Before refu-
el lin
g w

ith natural gas, make sure you add
the appropriate type of fuel ››› page 266.
Opening the fuel tank cap
The natural gas filler mouth is behind the fuel
tank cap, next to the petrol filler mouth.
● Unlock the vehicle with the key or with the
central
locking button  situated on the driv-
er door ››› page 125.
● Press on the rear area of the flap and open
it.
Ref

uelling
Special feature: if the ambient temperature is
very high, the natural gas pump protection
against overheating disconnects this auto-
matically.
● Remove the plug from the gas filler mouth
›››
Fig. 246 1 .
● Connect the pump filling nozzle to the gas
fi l
l

er mouth.
● The fuel tank will be full when the p
ump
compressor automatically cuts the supply. ●
If y
ou wish to finish refuelling in advance,
press the button on the pump to stop the
flow.
Closing the fuel tank cap
● Check that the gas filler mouth retainer 2 is not trapped with the filler nozzle. If neces-
s
ar
y

, place it in the filler mouth again.
● Insert the plug in the filler mouth.
● Close the tank flap. Make sure you hear it
click
into place. WARNING
Natural gas is a highly explosive, easily flam-
mab l

e substance. Incorrect handling of the
natural gas can cause accidents serious
burns and other injuries.
● Before refuelling with natural gas, engage
the fillin
g mouth correctly. If you can smell
gas, stop refuelling immediately. WARNING
The vehicle is not prepared to use liquefied
nat ur

al gas (LNG), and this fuel must not be
added under any circumstances. Liquefied
natural gas can cause the natural gas tank to
explode, resulting in serious injury. Note
● The fil lin

g nozzles of natural gas pumps
can differ in the way they are operated. If you do not know, ask a qualified employee at the
petro
l

station to do the refuelling.
● Noises heard when refuelling are normal
and do not indicat
e the presence of a fault in
the system.
● The vehicle natural gas system is prepared
both for ref
uelling with a small compressor
(slow refuel) and a large compressor (fast re-
fuel) in natural gas service stations. Fuel
Ty
pe

s of petrol The correct grade of petrol is listed inside the
f
uel
t

ank flap.
The vehicle is equipped with a catalytic con-
verter and must only be run on unleaded pet-
rol. The petrol must comply with European
Standard EN 228 or German standard DIN
51626-1 and must be unleaded. You can re-
fuel with a maximum ethanol proportion of
10 % (E10). The types of petrol are differenti-
ated by their octane rating (RON).
The following titles appear on the corre-
sponding adhesive on the fuel tank flap:
266

Checking and refilling levels
Super unleaded 95 octane or normal 91 oc-
t ane u
n
leaded petrol
We recommend you use super 95 octane pet-
rol. If this is not available: normal 91 octane
petrol, with a slight decrease in power.
Super unleaded petrol with a minimum of 95
octanes
You should use super petrol with a minimum
of 95 octanes.
If super is not available, in an emergency you
may refuel with normal 91 octane petrol. In
this case only use moderate engine speeds
and a light throttle. Refuel with super as soon
as possible.
Super unleaded 98 octane or super 95 oc-
tane unleaded petrol
We recommend you use super plus 98 octane
petrol. If this is not available: super 95 oc-
tane petrol, with a slight decrease in power.
If super is not available, in an emergency you
may refuel with normal 91 octane petrol. In
this case only use moderate engine speeds
and a light throttle. Refuel with super as soon
as possible.
Petrol additives
The quality of the fuel influences the behav-
iour, power and service life of the engine.
This is why the petrol you use should carry
suitable additives already included by the petrol industry, free of metals. These addi-
tives
will help to prevent corrosion, keep the
fuel system clean and prevent deposits from
building up in the engine.
If good-quality petrol with metal-free addi-
tives is not available or engine problems
arise, the necessary additives must be added
when refuelling ››› .
Not al
l

petrol additives have been shown to
be effective. The use of unsuitable petrol ad-
ditives may cause significant damage to the
engine and the catalytic converter. Metal ad-
ditives should never be used. Metal additives
may also be contained in petrol additives for
improving anti-detonation ratings or octane
ratings ››› .
S EA
T r

ecommends “genuine Volkswagen
Group Fuel Additives for petrol engines”.
These additives can be bought at SEAT deal-
ers, where information on how to use them
can also be obtained. CAUTION
● Do not r ef

uel if the filler indicates that the
fuel contains metal. LRP ( lead replacement
petrol) fuels contain high concentrations of
metal additives. Using them may damage the
engine!
● Never refuel with fuels containing a large
proportion of
ethanol (for example, E50, E85).
This could damage the fuel system. ●
Jus t

filling one full tank of leaded fuel or
fuel containing other metal additives would
seriously impair the efficiency of the catalytic
converter.
● Only use fuel additives that have been ap-
prov
ed by SEAT. Octane boosting or anti-
knock additives may contain metal additives
that could seriously damage the engine or
the catalytic converter. These additives must not be used.
● High engine speed and full throttle can
damag
e the engine when using petrol with an
octane rating lower than the correct grade for
the engine. Note
● You m a

y use petrol with a high octane num-
ber than the one recommended for your en-
gine.
● In those countries where unleaded petrol is
not avai
lable, you may refuel with a fuel with
a low lead content. Diesel fuel
Please note the information on the inside of
the f
uel
t

ank flap.
We recommend the use of diesel fuel which
complies to European standard EN 590. If
diesel fuel which meets European standard
EN 590 is not available, the Cetane number
(CZ) must, at minimum, be 51. If the engine »
267
Technical data
Advice
Operation
Emergencies
Safety

Advice
Engine compartment Chec k
in
g levels Fig. 247
Diagram for the location of the various elements. From time to time, the levels of the different
fluid
s
in the

vehicle must be checked. Never
fill with incorrect fluids, otherwise serious
damage to the engine may be caused.
Coolant expansion tank
Engine oil dipstick
Engine oil filler cap
Brake fluid reservoir
Vehicle battery (underneath the cover)
Windscreen washer reservoir
The checking and refilling of service fluids
are carried out on the components men-
tioned above. These operations are descri-
bed in ››› page 270.
1 2
3
4
5
6 Overview
Y
ou w
i
ll find further explanations, instruc-
tions and restrictions on the technical speci-
fications as of ››› page 289.
Working in the engine compartment Read the additional information carefully
›› ›

 page 17
Always be aware of the danger of injury and
scalding as well as the risk of accident or fire
when working in the engine compartment
(e.g. when checking and refilling fluids). Al-
ways observe the warnings listed below and
follow all general safety precautions. The en- gine compartment of the vehicle is a poten-
tia
l

ly hazardous area ››› .
WARNING
● Swit c

h the engine off, remove the key from
the ignition and apply the hand brake. If the
vehicle has a manual gearbox, place the lever
in neutral; if it has an automatic gearbox,
place the selector lever in position P. Wait for
the engine to cool down.
● Keep children away from the engine com-
partment
.
● Never spill liquids used for vehicle opera-
tion on the engine comp
artment, as these
may catch fire (e.g. the antifreeze in coolant). 270

Checking and refilling levels
●
Tak e c
are not to cause short circuits in the
electrical system, especially when working
on the battery.
● If working inside the engine compartment,
remember that, ev
en when the ignition is
switched off, the radiator fan may start up au-
tomatically, and therefore there is a risk of in-
jury.
● Never cover the engine with additional in-
sul
ating materials such as a blanket. Risk of
fire!
● Do not unscrew the cap on the coolant ex-
pans
ion tank when the engine is hot. The
cooling system is under pressure.
● Protect face, hands and arms by covering
the cap with a l
arge, thick rag to protect
against escaping coolant and steam.
● If it is necessary to work in the engine com-
partment
while the engine is running, the ro-
tating components (for example, poly-V belt,
alternator, radiator fan) and the high voltage
ignition system are an additional hazard.
● Observe the following additional warnings
if work
on the fuel system or the electrical
system is necessary:
– Always disconnect the battery from the
on-board network.
– Do not smoke.
– Never work near naked flames.
– Always keep an approved fire extinguish-
er immediately available. CAUTION
When topping up fluids make sure the correct
fluid is p

ut into the correct filler opening, oth-
erwise this can cause serious malfunctions or
engine damage. For the sake of the environment
Inspect the ground underneath your vehicle
re gu

larly so that any leaks are detected at an
early stage. If you find spots of oil or other
fluids in the area where it was parked, have
your vehicle inspected at the workshop. Note
In right-hand drive vehicles* some brake flu-
id re ser

voirs are on the other side of the en-
gine compartment ››› Fig. 247. Opening the bonnet
Read the additional information carefully
› ›
›

 page 17
The bonnet is released from inside the vehi-
cle.
Check that the windscreen wiper arms are
not unfolded. Otherwise the paint may be
damaged.
The bonnet can only be unlocked when the
driver door is open. WARNING
Never open the bonnet if you see steam or
drips of

coolant being released from the en-
gine compartment. Failure to comply could
result in burns. Wait until no steam or coolant
can be seen before opening the bonnet. Closing the bonnet
–
Slightly lift the bonnet.
– Release the bonnet stay before pressing it
bac k

into its support.
– Carefully close the bonnet.
– Press the bonnet down until it locks into
plac

e.
– Make sure that the bonnet catches onto its
cla

sp. Do not press down too hard ››› .
WARNING
● For s af

ety reasons the bonnet must always
be completely closed when the vehicle is
moving. Therefore, after closing the bonnet,
always check that the locking element is
properly engaged. This is the case if the bon-
net is flush with the adjacent body panels.
● Should you notice that the bonnet is not
safely
secured when the vehicle is moving,
stop the vehicle immediately and close the
bonnet. Failure to follow this instruction
could result in an accident. 271
Technical data
Advice
Operation
Emergencies
Safety