2012 Seat Mii check engine light

189
In the engine compartment
Engine coolant Introduction
Never work on the engine cooling system or if you are not familiar with the
operations 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. SEAT rec-
ommends visiting a Technical Service.
Negligent work can cause serious injury.
Additional information and warnings:
● Working in the engine compartment ⇒ page 180
● Accessories, parts replacement, repairs and modifications ⇒ page 222
WARNING
Engine coolant is toxic!
● Only keep engine coolant in its original container, tightly shut and in
a safe place.
● Never store engine coolant in empty food containers or bottles as
other people may accidentally drink it.
● Always keep engine coolant out of reach of children.
● Ensure that the proportion of engine coolant additive corresponds to
the lowest outside temperature to which the vehicle will be exposed.
● If the outside temperature is extremely low, the engine coolant could
freeze causing the vehicle to stop. As this would also cause the heating
to stop working, vehicle occupants without sufficient clothing could
freeze.
For the sake of the environment
Coolants and additives can contaminate the environment. Collect any spilt
fluids in suitable containers and dispose of in accordance with legislation
and with the utmost respect for the environment. 
Coolant warning lamp
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.
lights upPossible causeSolution

Excessive engine coolant
temperature. Stop the vehicle!
Stop the vehicle safely as soon as pos-
sible. Switch off the engine and let it
cool.
Insufficient engine cool-
ant level. ¡Stop the vehicle!
Check the engine coolant when the en-
gine has cooled and, if it is low, refill
with engine coolant ⇒ page 191.
Engine coolant system
faulty. Do not drive any further.
Obtain professional assistance.
flash- esPossible causeSolution
Engine coolant system
faulty.You should obtain professional assis-
tance. 
Vehicle diagramPrior to a journey...While drivingCare, cleaning and mainte-
nanceIf and whenTechnical Data

191
In the engine compartment
Checking the engine coolant level and refilling
Fig. 113 In the engine
compartment: Marking
on coolant expansion
tank
Fig. 114 In the engine
compartment: Coolant
expansion tank cap
If the coolant level is low, the coolant warning indicator will light. Preparations
●
Park the vehicle on even, flat and firm ground.
● Allow the engine to cool ⇒ 
.
● Open the bonnet  ⇒ page 180.
● The coolant expansion tank is easily recognisable because of the sym-
bol  on the cap ⇒  Fig. 114.
Checking the engine coolant level
● When the engine is cold, check the coolant level using the side marking
on the expansion tank ⇒ Fig. 113.
● If the level is below the “MIN” mark, top up with coolant. When the en-
gine is hot it may be slightly above the marked area.
Topping up the engine coolant level
● Always protect your face, hands and arms from hot coolant and steam
using a large, thick cloth over the coolant expansion tank cap.
● Remove the cap very carefully ⇒ 
.
● Only refill using new engine coolant according to SEAT specifications
(⇒ page 190) ⇒ 
.
● The engine coolant level should be between the marks on the coolant
expansion tank ⇒ Fig. 113. Do not exceed the top level of the marked area
⇒ 
.
● Screw on the cap tightly.
● If, the event of an emergency, you have no coolant that is compliant to
the required specifications ( ⇒ page 190), never use another type of addi-
tive. Instead, first top up with distilled water ⇒ 
only. Then re-establish
the correct proportion of the mixture with the correct additive as soon as
possible ⇒ page 190. 
Vehicle diagramPrior to a journey...While drivingCare, cleaning and mainte-
nanceIf and whenTechnical Data

194In the engine compartment
Warning lamp
lights
upPossible causeSolution
Faulty generator.
Contact a Specialised workshop.
Have the electrical system
checked.
Disconnect any unnecessary
electrical consumers. The gener-
ator does not charge the battery
while the vehicle is in motion.
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.
WARNING
If the warning lamps are ignored, the vehicle may stall in traffic, or may
cause accidents and severe injuries.
● Never ignore the warning lamps.
● Stop the vehicle safely as soon as possible.
CAUTION
Failure to heed the warning lamps when they appear may result in faults in
the vehicle. Checking the electrolyte level of the vehicle battery
Fig. 115 In the engine
compartment: Remove
the cover from the vehi-
cle's battery
The battery's electrolyte level should be checked regularly in high-mileage
vehicles, in hot countries and in older batteries. Other batteries do not re-
quire maintenance.
Vehicles fitted with the Start-Stop system are equipped with special batter-
ies. For technical reasons, the electrolyte level cannot be checked in these
batteries.
Preparations
● Prepare the vehicle for work in the engine compartment
⇒ page 180
● Open the bonnet 
⇒  page 180.
● Press on the tabs
⇒ Fig. 115 (arrows) in the direction of the arrows and
lift the battery cover up.
Checking the battery electrolyte level
● Make sure there is sufficient lighting to clearly recognise the colours.
Never use open flames or sparklers as a light source.
● Depending on the level of acid, the Magic eye on the top of the battery
will change colour. 

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
Vehicle diagramPrior to a journey...While drivingCare, cleaning and mainte-
nanceIf and whenTechnical Data

226Vehicle care and maintenance
Retro-fitting of two-way radios
An exterior aerial is required for the use of two-way radios in the vehicle.
The retro-fitting of electrical or electronic appliances in the vehicle is sub-
ject to their approval for use in your vehicle. Under certain circumstances,
this could mean that your vehicle registration documents are no longer val-
id.
SEAT has approved your vehicle for use with two-way radios providing the
following conditions are observed:
●The exterior aerial must be mounted professionally.
● The maximum transmitting power is 10 watts.
An only external aerial is needed to give the equipment its optimal reach.
Check first with a Specialised workshop if you wish to use a two-way radio
with a transmitting power of over 10 watts. The Specialised workshops are
familiar with the technical options for installation. SEAT recommends visit-
ing a Technical Service.
All legal requirements, together with the instructions for the use of two-way
radios must be observed.
WARNING
If the two-way radio is not securely fastened in position, it could be sent
flying around the vehicle in the event of sharp braking, sudden manoeu-
vres or accident, causing injury.
● While driving, two-way radios must be securely fastened in position,
outside the airbags deployment zones, or safely stowed away.
WARNING
When using a two-way radio without a connection to an exterior aerial,
the maximum permitted levels of electromagnetic radiation may be ex-
ceeded. This is also the case if the aerial has not been correctly installed.
● You should only use a two-way radio inside the vehicle if it has first
been correctly connected to an exterior aerial.

Information stored by the control units
Your vehicle is fitted at the factory with a series of electronic control units
responsible for the engine and gearbox management. In addition, the con-
trol units supervise the performance of the exhaust gas system and the air-
bag systems.
Therefore, while the vehicle is being driven, these electronic control units
are continuously analysing the vehicle data. In the event of faults or devia-
tions from the theoretical values, only this data is stored. Normally, the
warning lamps on the instrument panel light up in the event of faults.
This data can only be read and analysed using special equipment.
The storing of the data allows specialised workshops to detect and repair
faults. Stored data may include:
● Data relating to the engine or the gearbox
● Speed
● Direction of travel
● Braking force
● Detection of seat belt
The vehicle control units never record conversations held by passengers in
the vehicle. 

236Vehicle care and maintenance
Engine management and exhaust gas
purification system
Introduction
Additional information and warnings:
● Changing gear ⇒  page 124
● Refuelling ⇒  page 171
● Fuel ⇒ page 177
● Engine oil ⇒ page 185
● Vehicle battery ⇒ page 193
● Information stored in the control units ⇒ page 222
● Tow-starting and towing away ⇒ page 276
WARNING
The components of the exhaust system reach very high temperatures.
This could cause a fire.
● Always park your vehicle so that no part of the exhaust system can
come in contact with flammable materials (such as dried grass).
● Never apply additional underseal or anti-corrosion coatings to the ex-
haust pipes, catalytic converter or the heat shields on the exhaust sys-
tem.
 Control lamps
lights
upPossible causeSolution
Fault in engine management
(Electronic Power Control).Take the vehicle to a Specialised
workshop as soon as possible
and have the engine checked.
Fault in catalytic converter.
You should reduce speed accord-
ingly. Drive carefully until you
reach the next Specialised work-
shop. Have the engine checked
there.
flashesPossible causeSolution

Combustion fault which could
damage the catalytic convert-
er.You should reduce speed accord-
ingly. Drive carefully until you
reach the next Specialised work-
shop. Have the engine checked
there.
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.
CAUTION
Always pay attention to any lit lamps and to the corresponding descriptions
and instructions to avoid damage to the vehicle.
Note
While the control lamps  or  maintain lit up, the engine will present
faults, a higher consumption of fuel and a loss of engine power. 

238Practical information
If and when
Practical information
Frequently asked questions
If you suspect that the vehicle has a fault or is damaged when using it, be-
fore consulting a SEAT dealership or a specialised workshop, carefully read
the following instructions. Similarly, the terms in the alphabetical index
“Things to note” or “Checklist” may be of help.
ProblemPossible causes,
among othersPossible solution
The engine does
not start.
The vehicle battery is
flat.– Carry out the jump start
⇒ page 273.
– Charge the battery
⇒ page 193.
You are using an incor-
rect vehicle key.Use the correct key
⇒ page 28.
The fuel tank level is
insufficient.Refuel ⇒ page 171.
The vehicle cannot
be locked or un-
locked with the
key.
– Vehicle key battery is
flat.
– Too far away from
the vehicle.
– Buttons pressed out-
side the radius of
reach.– Change the battery
⇒ page 28.
– Move closer to the vehicle.
– Synchronize the vehicle
key ⇒ page 28.
– Manually lock or unlock
the vehicle ⇒ page 243.
Unusual noises.
Engine cold, City Safe-
ty Assist system, steer-
ing column electronic
lock.See entry “Noises” in the de-
tailed alphabetical index.
ProblemPossible causes,
among othersPossible solution
Handling is
strange.
Assistance systems ac-
tive.See entry “Assistance sys-
tems” in the detailed alpha-
betical index.
You are using an incor-
rect tyre pressure.Check the tyre pressure
⇒ page 210.
Damage to the wheel
trims or tyres.
Inspect wheel trims and
tyres regularly for damage
⇒ page 210 and replace
them if necessary
⇒ page 250.
Vehicle has no
jack, spare wheel
or tire mobility set
present.Equipment subject to
the vehicle.
No direct solution, depends
on the equipment. In this
case, you should contact a
SEAT Dealership
⇒ page 246.
Surface not correct-
ly illuminated.
– Headlights covered
for driving on the left-
hand side or right-
hand side.
– Headlight adjust-
ment too high.
– Faulty bulbs.
– Dipped headlights
switched off.– Cover the headlights for
driving on the left-hand side
or right-hand side
⇒ page 84.
– Adjust the headlight range
⇒ page 84.
– Change the bulbs
⇒ page 264.
– Switch on the dipped
headlights ⇒ page 84. 

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. 