engine Seat Mii 2012 Workshop Manual

171
At the filling station
At the filling station Refuelling
Introduction
The fuel tank plug is on the rear right of the vehicle.
Additional information and warnings:
● Exterior detail ⇒ page 6
● Fuel ⇒ page 177
● Working in the engine compartment ⇒ page 180
WARNING
Refuelling or handling fuel carelessly can cause an explosion or fire re-
sulting in serious burns and injuries.
● Always make sure that you correctly close the fuel tank flap to avoid
evaporation and fuel spillage.
● Fuels are highly explosive and inflammable substances that can
cause serious burns and injuries.
● Fuel could leak out or be spilt if the engine is not switched off or if the
filler fuel nozzle is not fully inserted into the tank filler mouth when refu-
elling. This could lead to a fire, explosion and severe injuries.
● When refuelling, turn off the engine and turn off the ignition for safe-
ty reasons.
● Always turn off mobile telephones, radio system apparatus and other
radio wave emitting equipment before refuelling. Electromagnetic waves
could cause sparks and lead to a fire.
WARNING (Continued)
● Never enter the vehicle while refuelling. If it is absolutely necessary
to enter the vehicle, close the door and touch a metal surface before
touching the filler nozzle again. This will prevent the generation of static
electricity. Sparks could cause a fire when refuelling.
● Never handle fuel close to open flames, sparks or objects with slow
combustion (e.g. cigarettes).
● Avoid static electricity and electro-magnetic radiation when refuel-
ling.
● Observe the safety regulations of the service station.
● Never spill fuel on the vehicle or in the luggage compartment.
WARNING
For safety reasons, SEAT does not recommend carrying a spare fuel canis-
ter in the vehicle. Fuel could be spilled and catch fire, above all in case of
an accident and this applies to a full container as well as empty contain-
ers. This could lead to explosions, fires and injuries.
● Observe the following if you exceptionally have to carry fuel in a can-
ister:
–Never place a fuel container, to fill it, inside the vehicle or on the
vehicle, for example, in the luggage compartment. Filling in these cir-
cumstances could create an electrostatic charge and spark that could
ignite fuel fumes.
– Always place the canister on the ground to fill it.
– Insert the fuel nozzle into the mouth of the canister as far as possi-
ble. 
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172At the filling station
WARNING (Continued)
– If you are using a metal fuel canister, the nozzle must always touch
the canister while it is being filled to avoid static electricity.
– Follow the legal requirements for the use, storage and transport of
spare fuel canisters.
– Insure that the fuel container complies with manufacturing stand-
ards, for example, ANSI or ASTM F852-86.
CAUTION
● Always remove any fuel spilled anywhere on the vehicle to avoid dam-
age to the wheel housing, the tyre and vehicle paintwork.
● Refuelling a petrol engine with diesel can cause serious engine and fuel
system damage; the resulting malfunctions are not covered by the SEAT
warranty. If you refuel with the wrong type of fuel, never start the engine.
This applies to even the smallest amount of the wrong fuel. You should ob-
tain professional assistance. With the engine running, the composition of
the wrong fuel could significantly damage the fuel system and the engine
itself.
For the sake of the environment
Fuels can contaminate the environment. Collect any spilt service fluids and
allow a professional to dispose of them. Control lamps and fuel gauge
Fig. 105 On the instru-
ment panel: fuel gauge
for petrol
Fig. 106 On the instru-
ment panel: fuel gauge
for petrol
The fuel gauge can vary depending on the vehicle equipment ⇒ Fig. 105
or ⇒ Fig. 106. 

173
At the filling station
lights upGauge position
⇒ Fig. 105Possible cause ⇒ Solution
 a)Red mark (ar-
row)The fuel tank is almost
empty.
The reserve tank is being
used ⇒ page 290.Refuel as soon as
possible ⇒ .
–The vehicle is running in
natural gas operating
mode.–
a)This only applies to vehicles with the fuel gauge on the instrument panel ⇒ Fig. 105.
flashes
for about 10 sec- ondsState of the barsPossible cause ⇒ Solution
 and
the seg-
ments re-
maining a)Reserve zone
(four small seg- ments)The fuel tank is almost
empty.
The reserve tank is being
used ⇒ page 290.Refuel as soon as
possible ⇒ .
–The vehicle is running in
natural gas operating
mode.–
a)This only applies to vehicles with the fuel gauge on the instrument panel display.
Several warning and control lamps light up for a few seconds when the igni-
tion is switched on while a test of the function is being carried out. They will
switch off after a few seconds.
In natural gas engines
The warning lamp  lights up when both fuel types (petrol and natural gas)
have reached reserve level.
The warning lamp  lights up when the vehicle is running in natural gas op-
erating mode. The warning lamp 
switches off when the natural gas is exhausted. The
engine changes to operate with petrol.
Problem: If the vehicle is left parked for a long time immediately after refuel-
ling, the gas level indicator does not accurately indicate the same level
shown after refuelling when the vehicle is started up again. This is not due
to a leak in the system, but to a drop in pressure in the gas tank for techni-
cal reasons after a cooling phase immediately after refuelling.
WARNING
Driving with insufficient fuel reserve could result in the vehicle breaking
down in traffic and a serious accident.
● If the fuel level is too low then the fuel supply to the engine can be-
come irregular especially on slopes.
● If the engine “is choked” or stalls due to lack of or irregularity of the
fuel supply, the power steering as well as all of the driver assistance sys-
tems including braking assistance will stop working.
● Always refuel when there is only one quarter of the fuel tank left to
avoid running out of fuel.
CAUTION
● Always pay attention to any lit lamps and to the corresponding descrip-
tions and instructions to avoid damage to the vehicle.
● Never run the fuel tank completely dry. An irregular fuel supply may lead
to ignition faults and unburnt fuel could enter the exhaust system. This
could damage the catalytic converter.
Note
The arrow next to the fuel pump symbol on the instrument panel ⇒ Fig. 105
indicates the side of the vehicle on which the fuel tank plug is located. 
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174At the filling station
Refuelling with petrol
Fig. 107 Open fuel tank
flap with tank plug at-
tached to the holder
Before refuelling, always turn off the engine, the ignition, mobile tele-
phones, auxiliary heating and keep them off during refuelling.
Opening the fuel tank flap
● The fuel tank plug is at the rear of the vehicle on the right.
● Pull the rear zone of the fuel tank flap to open.
● Unfold the key shaft if necessary
⇒ page 28.
● Insert the vehicle key into the lock cylinder of the fuel tank plug and turn
the key in an anticlockwise direction.
● Take out the fuel tank plug by turning it in an anticlockwise direction
and rest it on the upper part of the fuel tank flap ⇒ Fig. 107.
Refuelling
The correct petrol type for the vehicle is located on a sticker inside the fuel
tank flap ⇒ page 177. ●
If the automatic filler nozzle is operated correctly, it will switch itself off
as soon as the fuel tank is full ⇒ 
.
● Do not continue to refuel if it is turned off! Otherwise, this will fill the ex-
pansion chamber and fuel may leak out if the ambient conditions are warm.
Closing the fuel tank flap
● Screw on the fuel tank filler plug in a clockwise direction until it is fully
inserted with a click.
● Insert the vehicle key into the lock cylinder of the fuel tank plug, turn the
key in a clockwise direction and remove the key.
● Press the tank flap until it clicks into place. The fuel tank flap must be
flush with the body contour.
WARNING
Do not continue refuelling once the fuel nozzle has switched itself off.
The fuel tank may be filled too much. As a result, fuel may spurt out and
spill. This could lead to a fire, explosion and severe injuries.
CAUTION
● Always remove any fuel spilled anywhere on the vehicle to avoid dam-
age to the wheel housing, the tyre and vehicle paintwork.
For the sake of the environment
Fuels can contaminate the environment. Collect any spilt service fluids and
allow a professional to dispose of them. 

175
At the filling station
Refuelling with natural gas
Fig. 108 Tank flap open:
gas filler mouth 1, filler
mouth retainer 2
Before refuelling, the engine and the ignition, mobile telephone and heat-
ing must be switched off separately
⇒ .
It is also essential to carefully read the instructions for the natural gas
pump.
The vehicle is not prepared for refuelling with liquefied natural gas (LNG)
⇒ 
. Before refuelling with natural gas, make sure to add the appropriate
type of fuel.
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  situ-
ated on the driver door ⇒ page 36.
● Press on the rear area of the flap and open it. Refuelling
Problem: If the ambient temperature is very high, the natural gas pump pro-
tection against overheating disconnects this automatically.
●
Remove the plug from the gas filler mouth ⇒ Fig. 108 1
.
● Connect the pump filling nozzle to the gas filler mouth.
● The fuel tank will be full when the pump compressor automatically cuts
the supply.
● If you wish to finish refuelling in advance, press the button on the pump
to stop the flow.
Closing the fuel tank flap
● Check that the gas filler mouth retainer 2
is not trapped with the filler
nozzle. If necessary, 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 flammable substance. Incorrect
handling of the natural gas can cause accidents serious burns and other
injuries.
● Before refuelling with natural gas, the filling mouth must be correctly
engaged. If you can smell gas, stop refuelling immediately.
WARNING
The vehicle is not prepared to use liquefied natural 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. 
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176At the filling station
Note
● The filling nozzles of natural gas pumps can differ in the way they are
operated. If you are unacquainted with the pump, it is advisable that a
member of staff of the service station performs the refuelling operation.
● Noises heard when refuelling are normal and do not indicate the pres-
ence of a fault in the system.
● The vehicle natural gas system is prepared both for refuelling with a
small compressor (slow refuel) and a large compressor (fast refuel) in natu-
ral gas service stations. 
Refuelling precautions
Checklist
Never work on the engine or in the engine compartment if you are not famil-
iar with the operations to be carried out, the applicable safety standards
and if you do not have the instruments, liquids and tools necessary
⇒ page 180, Working in the engine compartment! In such a case, have any
work carried out by a Specialised workshop. Check the following regularly,
preferably when you refuel:
¥ Windscreen washer fluid level
⇒ page 91
¥ Engine oil level
⇒ page 185
¥ Engine coolant level
⇒ page 189
¥ Brake fluid level
⇒ page 134
¥ Tyre pressure ⇒ page 210
¥ Vehicle lighting required to guarantee road safety:
– Turn signals
– Side lights, dipped beam and main beam headlights
– Rear lights
– Brake lights
– Rear fog light ⇒ page 84
Information on bulb replacement ⇒ page 264. 

177
At the filling station
Fuel
Introduction
You will find a factory-fitted sticker containing information on the type of
fuel for your vehicle on the inside of the fuel tank flap.
Additional information and warnings:
● ⇒ Booklet Maintenance Programme
● Refuelling ⇒ page 171
● Electronic power control and exhaust gases purification system
⇒ page 236
WARNING
Refuelling or handling fuel carelessly can cause an explosion or fire re-
sulting in serious burns and injuries.
● Fuel is a highly explosive, easily flammable substance.
● Observe current safety instructions and local regulations concerning
the handling of fuel.

Types of fuel
The type of fuel to use when refilling will depend on the vehicle's engine.
You will find a factory-fitted sticker containing information on the type of
fuel for your vehicle on the inside of the fuel tank flap.
SEAT recommends the use of sulphur-free or low sulphur fuel to reduce con-
sumption and prevent engine damage.
Possible types of fuelAlternative namesFurther information
91a)
RONNormal petrol, normal unlea-
ded petrol
⇒ page 17795 a)
RONPremium unleaded petrol (95
RON)
98 a)
RONPremium unleaded petrol (98
RON)
a) RON = Regulation Octane Number 
Petrol
Petrol types
Vehicles with petrol engines must refuel using unleaded petrol according to
European norm EN 228 ⇒ 
.
Petrol types are categorised according to their octane number (e.g. 91, 95,
98 or 99 RON (RON = “Research Octane Number”). You may use petrol with
a high octane number than the one recommended for your engine. Howev-
er, this has no advantage in terms of fuel consumption and engine power.
SEAT recommends refuelling with a low sulphur content or sulphur-free fuel
to reduce fuel consumption for petrol engines.
Petrol additives
The quality of the fuel influences running behaviour, performance and serv-
ice life of the engine. Therefore, it is recommended to refuel with good qual-
ity petrol containing the corresponding petrol additives. These additives will
help to prevent corrosion, keep the fuel system clean and prevent deposits
from building up in the engine.
If good quality petrol with additives are not available or engine problems
arise, the necessary additives must be added when refuelling ⇒ 
.
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178At the filling station
Not all petrol additives have been shown to be effective. The use of unsuita-
ble petrol additives could seriously damage the engine and the catalytic
converter. Petrol additives with metal additives must never be used.
Available petrol additives for improvements in Anti-detonation ratings or oc-
tane ratings may contain metal additives ⇒ 
.
SEAT recommends “Genuine SEAT Additives for petrol engines”. These addi-
tives are available from Specialised workshops, who will inform you of their
application.
CAUTION
● Only use fuel with an octane rating that is in line with the norm EN 228,
otherwise significant damage could be caused to the engine and fuel sys-
tem. Furthermore, it could lead to a loss of performance with the conse-
quent engine fault.
● The use of unsuitable petrol additives could seriously damage the en-
gine and the catalytic converter.
● If, in exceptional circumstances, petrol with a lower octane rating to that
recommended is used, only use moderate engine speeds and a light throt-
tle. Avoid using full throttle and overloading the engine. Otherwise engine
damage may occur. Fill up with fuel of a suitable octane rating as soon as
possible.
● Do not refuel if the filler indicates that the fuel contains metal. LRP (lead
replacement petrol) fuels also contain high concentrations of metal addi-
tives. This could damage the engine!
● Just filling one full tank of leaded fuel or with other metal additives
would seriously impair the efficiency of the catalytic converter and could
damage it. 
Natural gas
Natural gas, in addition to others, can be in liquid form. Liquefied natural gas (LNG) is the result of heavy cooling of natural gas.
Therefore its volume is considerably reduced compared with compressed
natural gas (CNG). In vehicles with a natural gas engine, liquefied natural
gas cannot be directly refilled, given that the gas would expand excessively
in the vehicle gas tank.
Therefore, vehicles with a natural gas engine must only be refuelled using
compressed natural gas
⇒ 
.
Natural gas quality and consumption
Natural gas is divided into the groups H and L depending on its quality.
Gas type H has a superior heating power and inferior nitrogen and carbon
dioxide content than type L. The higher the heating power of the natural
gas, the lower the consumption will be.
However, the heating power and the proportion of nitrogen and carbon di-
oxide can fluctuate within the quality groups. Therefore, vehicle consump-
tion can also vary when using one type of gas only.
The engine management automatically adapts to the natural gas used ac-
cording to its quality. Therefore, different quality gases can be mixed in the
tank, without the need for comprehensive draining before applying a differ-
ent quality gas.
Natural gas and safety
If you can smell gas or suspect that there is a leak ⇒ 
:
● Stop the vehicle immediately.
● Switch the ignition off.
● Open the doors to appropriately ventilate the vehicle.
● Immediately extinguish cigarettes.
● Move away from the vehicle or switch off objects that may cause sparks
or a fire.
● If you continue to smell gas, do not continue driving!
● You should obtain professional assistance. Have the fault repaired. 

180In the engine compartment
Care, cleaning and maintenance
In the engine compartment
Working in the engine compartmentIntroduction
Before working in the engine compartment, make sure that the vehicle is
parked on horizontal and firm ground.
The engine compartment of the vehicle is a hazardous area. Never work on
the engine or in the engine compartment if you are not familiar with the op-
erations to be carried out, the applicable safety standards and especially if
you do not have the instruments, liquids and tools necessary ⇒ 
! In such
a case, have any work carried out by a Specialised workshop. Negligent
work can cause serious injury.
Additional information and warnings:
● Exterior detail ⇒ page 6
● Windscreen wash system ⇒ page 91
● Start and stop the engine ⇒ page 119
● Brake fluid ⇒ page 134
● Checks when filling up ⇒ page 171
● Engine oil ⇒ page 185
● Engine coolant ⇒ page 189
● Vehicle battery ⇒ page 193
● Accessories, parts replacement, repairs and modifications ⇒ page 222
WARNING
If the vehicle moves unexpectedly, this could cause serious injury.
● Never work underneath the vehicle if it is not secured against moving.
If you must work underneath the vehicle with the wheels in contact with
the ground then it should be parked on flat ground, the wheels should be
prevented from moving and the key must be removed from the ignition.
● If you have to work underneath the vehicle, you must use suitable
stands additionally to support the vehicle, there is a risk of accident!.
The jack is not intended for this kind of work and its failure could lead to
severe injuries.
● Disconnect the Start-Stop system.
WARNING
The engine compartment is a dangerous area capable of causing serious
injury.
● For all type of work, always take the utmost precautions, work care-
fully and note the general safety standards in force. Never take personal
risks.
● Never work on the engine or in the engine compartment if you are not
familiar with the necessary operations. If you are not sure about proce-
dures then visit a Specialised workshop to carry out the necessary work.
Incorrect work can cause serious injuries. 

181
In the engine compartment
WARNING (Continued)
● Never open the bonnet if you see steam or coolant escaping from the
engine compartment. Hot vapours and coolant can cause serious burns.
Always wait until you cannot see or hear the sound of steam or coolant
coming from the engine compartment.
● Always allow the engine to cool down before opening the bonnet.
● Contact with hot elements of the engine and the exhaust system can
cause burns.
● Once the engine has cooled, follow the instructions below before
opening the bonnet:
–Engage the handbrake and place the gear selector lever in P or the
gear stick in neutral.
– Remove the key from the ignition.
– Keep children away from the engine compartment and never leave
them unsupervised.
● When the engine is warm or hot, the cooling system is pressurised.
Do not unscrew the cap on the coolant expansion tank when the engine
is hot. Otherwise, coolant may spray out under pressure causing burns
and serious injury.
–After cooling, carefully and slowly unscrew the cap anticlockwise,
gently pressing down on it.
– Always protect your face, hands and arms from hot coolant and
steam using a large, thick cloth.
● When refilling liquids, avoid spilling them on parts of the engine and
the exhaust system. Spilled liquids could cause a fire.WARNING
The high voltages of the electrical system can give electric shocks as well
as causing burns and serious injury and possibly even death!
● Never cause short circuits in the electrical system. The battery could
explode.
● To minimise the risk of electric shock and serious consequences
while the engine is running or starting the engine, note the following:
–Never touch the electrical wiring of the ignition system.
WARNING
In the engine compartment, there are rotating parts that could cause se-
rious injury.
● Never place your hands directly on or near the radiator fan. Touching
the rotor blades could seriously harm you. The ventilator works accord-
ing to the engine temperature and could start suddenly even when the ig-
nition is turned off and the key is removed.
● If any work has to be performed when the engine is started or with
the engine running, there is an additional, potentially fatal, safety risk
from the rotating parts, such as the drive belts, alternator, radiator fan
etc as well as from the high-voltage ignition system. Always work with
the utmost caution.
–Always make sure that no parts of your body, jewellery, ties, loose
clothing and long hair can be trapped by the rotating parts of the en-
gine. Before any work, remove ties and jewellery ( necklaces, etc), tie
longhair back and tie all items of loose clothing to your body to make
sure that they cannot be trapped by engine components.
– Take extreme caution when operating the accelerator and remain
attentive. The vehicle could move, even if the handbrake is applied.
● Always make sure you have not left any objects, such as cloths or
tools, in the engine compartment. If any object is left in the engine com-
partment, this could cause malfunctions, engine faults and even a fire. 
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