ignition Seat Mii 2012 Workshop Manual

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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196In the engine compartment
the maximum service intervals permitted ⇒ Booklet Maintenance
Programme.
Automatic consumer disconnection
The intelligent vehicle electrical system automatically implements a range
of measures to prevent the battery from discharging when high demands
are made on it:
● the idling speed is increased so that the alternator provides more elec-
tricity.
● where necessary, the power of the most powerful consumers is reduced
or even completely disconnected.
● On starting the engine, the power supply from the 12-volt socket and
the cigarette lighter may be interrupted for a short time.
The on-board management program cannot always prevent the battery from
running flat. For example, if the ignition is left on for a long period with the
engine off or if the side lights or parking lights are left on while the vehicle
is stationary.
Why the battery runs flat:
● When stationary for a long time without starting the engine, particularly
if the ignition is switched on.
● Use of electrical consumers with the engine switched off.
WARNING
Incorrectly securing the battery or using the wrong battery can cause
short-circuits, fire and serious injuries.
● Always use only maintenance free batteries, protected to prevent a
leak, and whose properties, specifications and size correspond to the
standard battery.
WARNING
A highly explosive mixture of gases is released when the battery is under
charge.
● The batteries should be charged in a well-ventilated room only.
● Never charge a frozen or recently thawed battery. A flat battery can al-
so freeze at temperatures close to 0 °C (+32 °F).
● Always replace a battery which has frozen.
● Battery cables not correctly connected may cause a short circuit. Re-
connect first the positive cable and then the negative cable.
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.
● Never plug accessories supply current, such as solar panels or a battery
charger, to the 12-volt socket or the cigarette lighter. This could damage the
vehicle's electrical system.
For the sake of the environment
Dispose of the battery in an environment-friendly manner. Batteries contain
toxic substances such as sulphuric acid and lead.
For the sake of the environment
Battery acid can contaminate the environment. Collect any spilt service flu-
ids and allow a dispose of them correctly. 

240Practical information
In case of emergency
Introduction
Additional information and warnings:
● Braking, stopping and parking ⇒ page 134
● Emergency locking and unlocking ⇒ page 243
● Vehicle tools ⇒ page 246
● Change wheel ⇒ page 250
WARNING
A faulty vehicle in traffic represents a risk of accident for the driver and
for other road users.
● Stop the vehicle safely as soon as possible. Park the vehicle a safe
distance from surrounding traffic to lock all the doors in case of an emer-
gency. Turn on the hazard warning lights to warn other road users.
● Never leave children or disabled people alone in the vehicle if the
doors are to be locked. In case of an emergency, passengers will be trap-
ped inside the vehicle. Individuals locked in the vehicle can be exposed
to very high or very low temperatures.
 Protecting yourself and securing the vehicle
Fig. 130 Dash panel:
Button to switch on and
off the hazard warning
lights system
Always fulfil legal requirements for securing a broken down vehicle. In a
number of countries it is now obligatory, for example, to turn on the hazard
warning lights and use a reflective safety vest ⇒ page 242.
Checklist
For your own safety and that of other passengers, the following points
should be observed in the order given ⇒ 
:
1. Park the vehicle a safe distance from traffic and on suitable ground ⇒ 
.
2. Turn on the hazard warning lights system with the button 
⇒ Fig. 130.
3. Apply the handbrake firmly ⇒ page 134.
4. Put the gearbox lever in neutral or the selector lever in position P ⇒ page 124.
5. Switch off the engine and remove the key from the ignition.
6. Have all occupants leave the vehicle and move to safety, for example behind a guard rail. 

241
Practical information
Checklist (Continued) 7. When leaving the vehicle, take all keys with you.
8. Place an emergency warning triangle to indicate the position of your vehicle to other road users.
9. Allow the engine to cool and check if a specialist is required.
When being towed with the hazard warning lights system on, a change in
direction or traffic lane can be indicated as usual using the turn signals lev-
er. The hazard lights will be interrupted temporarily.
Examples of when to use the hazard warning lights system:
● If the vehicles ahead suddenly slow down or reach the end of a traffic
jam, to warn the vehicles behind.
● In case of an emergency.
● If the vehicle breaks down.
● When tow-starting or towing.
Always comply with the applicable laws regarding the use of hazard warn-
ing lights.
If the hazard warning lights system is not working, you must use an alterna-
tive method of drawing attention to your vehicle. This method must comply
with traffic legislation.
WARNING
Failure to follow the checklist prepared for your own safety could lead to
accidents and severe injuries.
● Always complete the operations given in the checklist and observe
the general rules of safety.
WARNING
The components of the exhaust system reach very high temperatures.
This could cause a fire and considerable damage.
● Always park your vehicle so that no part of the exhaust system can
come in contact with flammable materials (such as dried grass or fuel).
Note
The vehicle battery will discharge and run down if the hazard warning lights
remain on for too much time (even with the ignition turned off).
Note
For some vehicles, the brake lights will blink when braking suddenly at
speeds of approximately 80 km/h (50 mph) to warn vehicles behind. If brak-
ing continues, then the hazard warning lights system will automatically be
turned on at the speed of less than approximately 10 km/h (6 mph). The
brake lights remain lit. Upon accelerating, the hazard warning lights system
will be automatically turned off. 
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251
Practical information
Preparations for changing a wheel
Check list
Before changing a wheel, complete the following operations in the order
given ⇒ 
:
1. In the event of a flat tyre, park the vehicle a safe distance from traffic and on suitable ground.
2. Apply the handbrake firmly ⇒ page 134.
3. Automatic gearbox: move the selector lever to position P
⇒ page 124.
4. Stop the engine and remove the key from the ignition ⇒ page 119.
5. Manual gearbox: Select a gear ⇒ page 124.
6. Have all vehicle occupants get out of the vehicle and wait in a safe place (for example, behind the safety barrier).
7. Chock the wheel opposite the wheel being changed with a stone or similar object.
8. If the luggage compartment is full: take the baggage out of the vehi- cle.
9. Remove the spare wheel or the temporary spare wheel and the vehi- cle tool kit from the luggage compartment.
10. Remove the wheel trims ⇒ page 248.
WARNING
Failure to follow the checklist prepared for your own safety could lead to
accidents and severe injuries.
● Always complete the operations given in the checklist and observe
the general rules of safety.
 Wheel bolts
Fig. 141 Changing the
wheel: Slacken the wheel
bolts
Fig. 142 Changing the
wheel: Tyre valve
1 and
position of anti-theft
wheel locking bolt 2
Only use the tool supplied with the vehicle to loosen the wheel bolts.
Loosen the wheel bolts only about one turn before raising the vehicle with
the jack.

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