2012 Seat Mii ignition

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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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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182In the engine compartment
WARNING
Refill liquids and certain materials can catch fire easily in the engine
compartment, causing a fire and serious injury!
● Never smoke.
● Never work close to places exposed to flames or sparks.
● Never pour service fluids over the engine. These fluid may ignite hot
engine parts and cause injuries.
● If it is necessary to work on the fuel system or the electrical system,
please follow the instructions below:
–Always disconnect the vehicle battery.
– Never work close to heaters, heat sources or places exposed to
flames or sparks.
● Always keep a recently serviced and perfectly working fire extin-
guisher close by.
CAUTION
When refilling or changing service liquids, ensure that you put the liquids
into the right tank. Making a mistake when refilling could cause serious
malfunctions and damage the engine!
For the sake of the environment
Service fluids leaks are harmful to the environment. For this reason you
should make regular checks on the ground underneath your vehicle. Take
the vehicle to a Specialised workshop to be checked if you see stains, oil or
other fluids on the ground. Collect any spilt service fluids and allow a pro-
fessional to dispose of them. Preparing the vehicle for work in the engine compartment
Checklist
Carry out the operations below in the order indicated before starting work in
the engine compartment
⇒ 
:
¥ Park the vehicle on an even and solid surface.
¥ Press and hold the brake pedal until the vehicle comes to a stand-
still.
¥ Apply the handbrake firmly
⇒ page 134.
¥ Move the gear lever into the neutral position
⇒ page 124.
¥ Stop the engine and remove the key from the ignition
⇒ page 119.
¥ Wait for the engine to cool down.
¥ Always keep children and other people far from the engine compart-
ment.
¥ Ensure that the vehicle can not move off unexpectedly.
WARNING
Always complete the operations given in the checklist and observe the
general rules of safety.
● Ignoring this checklist, drawn up for your own safety, could result in
serious injury.


192In the engine compartment
WARNING
Hot vapours and coolant can cause serious burns.
● Never open the coolant expansion tank if steam or coolant is coming
from the engine compartment. Wait until you cannot see or hear any
steam or coolant escaping.
● Always wait until the engine has completely cooled before very care-
fully opening the expansion tank cap. Contact with hot elements of the
engine can cause skin 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.
–Carefully and slowly unscrew the cap anticlockwise, gently press-
ing 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. Under specific cir-
cumstances, the ethylene glycol can catch fire.CAUTION
● Top up with distilled water only. Any other type of water may lead to con-
siderable rusting in the engine due to its chemical components. This could
consequently damage the engine. If you have not used distilled water but
another type of water to top up the coolant, a Specialised workshop must
immediately replace all of the fluid in the engine cooling system.
● Only top up coolant to the top level of the marked area ⇒ Fig. 113. Oth-
erwise the excess coolant will be forced out of the cooling system when the
engine is hot, causing damage.
● If a lot of liquid coolant has been lost, wait for the engine to cool down
completely before adding coolant. Extensive coolant loss is an indication of
leaks in the engine cooling system. Have the engine cooling system inspec-
ted immediately by a Specialised workshop. Otherwise engine damage may
occur.
● When refilling or changing service liquids, ensure that you put the liq-
uids into the right tank. Making a mistake when refilling could cause seri-
ous malfunctions and damage the engine! 

193
In the engine compartment
Vehicle battery
Introduction
The battery is a component of the vehicle's electrical system.
Never work on the electrical system without fully understanding the opera-
tions required, the applicable safety standards and without the correct tools
⇒ 
! In such a case, have any work carried out by a Specialised workshop.
SEAT recommends visiting a Technical Service. Negligent work can cause
serious injury.
Location of the vehicle battery
The battery is located in the engine compartment.
Explanation of the warning indications on the vehicle's battery
SymbolMeaning
Wear eye protection!
Battery acid is very corrosive and caustic. Always wear
protective gloves and eye protection!
Fires, sparks, open flames and smoking are prohibited.
A highly explosive mixture of gases is released when
the battery is under charge.
Keep children away from acid and batteries!
Additional information and warnings:
● ⇒ Booklet Maintenance Programme
● Working in the engine compartment ⇒ page 180
● Accessories, parts replacement, repairs and modifications ⇒ page 222
WARNING
Working on the vehicle battery and the electrical system can cause corro-
sion, fire and electric shocks. Always read and take into account the fol-
lowing warnings and safety standards before carrying out any work:
● Before working on the battery, switch off the engine, the ignition and
all electrical devices then disconnect the negative connection on the bat-
tery.
● Keep children away from acid and the battery itself!
● Wear eye protection.
● Battery acid is very corrosive and caustic. It can burn skin and cause
blindness. When handling the battery, protect yourself from splashes of
acids, above all your hands, arms and face.
● Do not smoke and never work close to places exposed to flames or
sparks.
● Avoid sparks and electrostatic discharges when working with cables
and electrical devices.
● Never short the battery terminals.
● Never use a damaged battery. It can explode. Replace a damaged bat-
tery immediately.
● Replaced damaged or frozen batteries as soon as possible. A flat bat-
tery can also freeze at temperatures close to 0 °C (+32 °F).
CAUTION
● Never disconnect the battery if the ignition is switched on or if the en-
gine is running. This could damage the electrical system or electronic com-
ponents.
● Do not expose the battery to direct sunlight over a long period of time,
as the intense ultraviolet radiation can damage the battery housing.
● If the vehicle is left standing for long periods, protect the battery from
extreme cold temperature so that it does not “freeze up” and become dam-
aged. 
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195
In the engine compartment
Colour indicatorNecessary operations
light yellow or col-
ourlessThe electrolyte level of the vehicle's battery is too low.
Have the battery checked and, where applicable, re-
placed by a Specialised workshop.
blackThe electrolyte level of the vehicle's battery is correct.
WARNING
Working with the vehicle battery involves a risk of corrosion, explosions
and electric shock.
● Always wear protective gloves and eye protection.
● Battery acid is very corrosive and caustic. It can burn skin and cause
blindness. When handling the battery, protect yourself from splashes of
acids, above all your hands, arms and face.
● Never tilt the vehicle battery. Battery acid could spill out of the open-
ings to release gases and cause corrosion damage.
● Never open the vehicle battery.
● If battery acid splashes on you, immediately rinse your eyes and skin
abundantly with water for several minutes. Then seek medical care imme-
diately.
● If acid is swallowed by mistake, consult a doctor immediately.

Charging, replacing and connecting or disconnecting the
battery
Charging the battery
The vehicle battery should be charged by a specialised workshop only, as
batteries using special technology have been installed and they must be
charged in a controlled environment ⇒ 
. SEAT recommends visiting a
Technical Service. Replacing a vehicle battery
The battery has been developed to suit the conditions of its location and
has special safety features. If the battery must be replaced, consult a Tech-
nical Service for information on electromagnetic compatibility, the size and
maintenance, performance and safety requirements of the new battery in
your vehicle before you purchase one. SEAT recommends you have the bat-
tery replaced by a Technical Service.
Use only maintenance-free genuine batteries conforming to TL 825 06 and
VW 7 50 73 Standards. These standards must be dated April 2008 or later.
Vehicles fitted with the Start-Stop system are equipped with a special bat-
tery. Therefore, this battery must only be replaced by another of the same
specifications.
Disconnecting the vehicle's battery
If you must disconnect the battery from the electrical system, please note
the following:
●
Switch off the ignition and all electrical equipment.
● The vehicle must be unlocked before disconnecting the battery, other-
wise the alarm will be triggered.
● First disconnect the negative cable and then the positive ⇒ 
.
Connecting the vehicle's battery
● Before reconnecting the battery, switch off the engine, the ignition and
electric devices.
● First reconnect the positive cable and then the negative ⇒ 
.
Different control lamps may light up after connecting the battery and switch-
ing the ignition on. They will be turned off after a short trip at a speed of
between 15 - 20 km/h (10 - 12 mph). If the warning indicators remain lit,
please visit a specialised workshop to have the vehicle checked.
If the battery has been disconnected for a long time, it is possible that the
next service date is not displayed or calculated correctly ⇒ page 17. Respect
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