Seat Mii 2012 Repair Manual

59
Ensuring you are correctly and safely seated
The seat belt status is displayed for around 30 seconds when a seat belt in
the rear seats is fastened or unfastened. You can switch off this display by
pressing the 0.0 / SET
button.
The seat belt status flashes for a maximum of 30 seconds when a seat belt
in the rear seats is unfastened while the vehicle is in motion. An audible
warning will also be heard if the vehicle is travelling at over 25 km/h
(15 mph).
WARNING
Unbuckled or badly buckled seat belts increase the risk of severe or even
fatal injuries. The optimal protection from seat belts can be achieved only
if you use them properly.

Frontal collisions and the laws of physics
Fig. 37 Vehicle about to
hit a wall: the occupants
are not wearing seat
belts
Fig. 38 The vehicle hits
the wall: the occupants
are not wearing seat
belts
It is easy to explain how the laws of physics work in the case of a head-on
collision: when a vehicle starts moving ⇒ Fig. 37, this is a certain amount of
energy known as “kinetic energy” both in the vehicle and in the occupants.
The higher the speed and the greater the weight of the vehicle, the more
energy there is to be absorbed in an accident.
The most significant factor, however, is the speed of the vehicle. If the
speed doubles from 25 km/h (15 mph) to 50 km/h (30 mph), for example,
the kinetic energy is multiplied by four.
The amount of “kinetic energy” depends on the speed of the vehicle and
the weight of the vehicle and its passengers. The higher the speed and the
greater the weight of the vehicle and the occupants, the more energy there
is to be absorbed in an accident.
Vehicle occupants not wearing seat belts are not “attached” to the vehicle.
As a result, in a frontal collision they will continue to move forward at the
speed their vehicle was travelling just before the impact until something
stops them! Because the passengers in our example are not restrained by
seat belts, all of the vehicle occupants' kinetic energy has to be absorbed at
the point of impact ⇒ Fig. 38.

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60Ensuring you are correctly and safely seated
At speeds of 30 km/h (18 mph) to 50 km/h (30 mph), the forces acting on
bodies in a collision can easily exceed one tonne (1000 kg or
2.205 pounds). At greater speed these forces are even higher.
This example applies not only to frontal accidents, but to all accidents and
collisions. 
Dangers of not using the seat belt
Fig. 39 A driver not
wearing a seat belt is
thrown forward violently
Fig. 40 The unbelted
rear seat passenger is
thrown forward violently,
hitting the driver wearing
a seat belt
Many people believe that the occupants can protect themselves with their
hands in a minor collision. This is false!
Even at low speeds, the forces acting on the body in a collision are so great
that it is not possible to brace oneself with just one's arms and hands. In a
frontal collision, unbelted vehicle occupants are thrown forward and will
make violent contact with the steering wheel, dash panel, windscreen or
whatever else is in the way ⇒ Fig. 39.
The airbag system is not a substitute for seat belts. When triggered, airbags
provide only additional protection. Airbags do not deploy in all types of ac-
cident. All occupants (including the driver) must be wearing seat belts prop-
erly during the trip, even if the vehicle is equipped with airbag systems.
This will reduce the risk of critical or fatal injuries in the event of an accident
– regardless of whether an airbag is fitted for the seat.
The airbag is only deployed once. To achieve the best possible protection,
the seat belt must always be worn properly so that you will be protected in
accidents in which no airbag is deployed. Vehicle occupants not wearing
belts could be thrown from the vehicle and sustain even more severe or fa-
tal injuries. 

61
Ensuring you are correctly and safely seated
It is also important for the rear passengers to wear seat belts properly, as
they could otherwise be thrown forward violently in an accident. Rear seat
passengers who do not use seat belts endanger not only themselves but al-
so the driver and other occupants ⇒ Fig. 40. 
Seat belt protection
Fig. 41 Drivers with
properly worn seat belts
will not be thrown for-
ward in the event of sud-
den braking
Wearing a correctly fastened seat belt can significantly change the situa-
tion. Properly worn seat belts hold the vehicle occupants in the correct sit-
ting positions and substantially reduce the kinetic energy in the event of an
accident. Seat belts also help to prevent uncontrolled movements that
could lead to severe injuries. In addition, properly worn seat belts reduce
the danger of being thrown from the vehicle ⇒ Fig. 41.
Vehicle occupants wearing their seat belts correctly benefit greatly from the
ability of the belts to absorb kinetic energy. The front crumple zones and
other passive safety features (such as the airbag system) are also designed
to absorb the kinetic energy generated in a collision. Taken together, all
these features reduce the energy released and decrease the risk of injury. Our examples describe frontal collisions. Of course, properly worn seat belts
substantially reduce the risk of injury in all other types of accidents. This is
why it is so important to fasten seat belts before every trip, even when just
driving “around the corner”. Ensure that your passengers wear their seat
belts as well.
Accident statistics have shown properly worn seat belts to be an effective
means of considerably reducing the risk of severe injury and improving the
chances of survival in a serious accident. Furthermore, properly worn seat
belts improve the protection provided by deployed airbags in the event of
an accident. For this reason, wearing a seat belt is required by law in most
countries.
Although your vehicle is equipped with airbags, fasten and wear the seat
belts. The front airbags, for example, are only triggered in some frontal acci-
dents. The front airbags will not be triggered during minor frontal collisions,
minor side collisions, rear collisions, rolls or accidents in which the airbag
trigger threshold value in the control unit is not exceeded.
Therefore, you should always wear your seat belt and ensure that vehicle
occupants have fastened their seat belts properly before you drive off!

Using seat belts
Checklist
Use of the seat belt ⇒ 
:
¥ Check the condition of all the seat belts at regular intervals.
¥ Keep the seat belts clean.
¥ Keep the seat belt web, the latch plate and the buckle free of foreign
bodies and liquids.
¥ Do not jam or damage the seat belt or the latch plate when closing
the door, for example.

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62Ensuring you are correctly and safely seated
Checklist (Continued) ¥ Never remove, modify or repair the seat belt or belt fastening mecha-
nisms.
¥ Fasten your seat belt properly before each trip and keep it fastened.
Twisted seat belt
If it is difficult to remove the seat belt from the guide, the seat belt may
have become twisted inside the side trim after being wound too quickly on
unfastening:
●
Pull out the seat belt completely, carefully pulling on the latch plate.
● Untwist the belt and guide it back, assisting it by hand.
Fasten the seat belt even if it is impossible to untwist it. In this case, the
twisted area must not be in an area in direct contact with your body. Have
the seat belt untwisted urgently by a Specialised workshop.
WARNING
An improperly handled seat belt increases the risk of sustaining severe
or fatal injuries.
● Regularly check that the seat belts and their components are in per-
fect condition.
● Always keep your seat belt clean.
● Do not jam or damage the seat belt or rub it with sharp edges.
● Make sure there are no liquids or foreign bodies on the latch plate
and in the buckle.
 Fastening or unfastening a seat belt
Fig. 42 Insert the latch
plate into the buckle
Fig. 43 Release the latch
plate from the buckle
Properly worn seat belts hold the vehicle occupants in the position that
most protects them in the event of an accident or sudden braking ⇒ 
.

63
Ensuring you are correctly and safely seated
Fastening the seat belt
Fasten your seat belt before each trip.
● Correctly adjust the front seat ⇒ page 48.
● Engage the seat backrest in the upright position and correctly adjust the
hear restraint ⇒ 
.
● Pull the latch plate and place the belt webbing evenly across your chest
and lap. Do not twist the seat belt when doing so ⇒ 
.
● Engage the latch plate in the buckle of the corresponding seat ⇒ Fig. 42.
● Pull the belt to ensure that the latch plate is securely engaged in the
buckle.
Unfastening the seat belt
The seat belt must not be unfastened until the vehicle has come to a stand-
still ⇒ 
. ●
Press the red button on the buckle ⇒ Fig. 43. The latch plate is released
from the buckle.
● Guide the belt back by hand so that it rolls up easily and the trim will not
be damaged.
WARNING
An incorrectly worn seat belt web can cause severe or fatal injuries in the
event of an accident.
● The seat belt cannot offer its full protection unless the backrests are
in an upright position and the seat belt is worn correctly, according to
your size.
● Unbuckling your seat belt while the vehicle is in motion can cause se-
vere or fatal injuries in the event of an accident or sudden braking.

Seat belt position
Fig. 44 Correct seat belt position 
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64Ensuring you are correctly and safely seated
Fig. 45 Correct position-
ing of seat belts during
pregnancy
Seat belts offer their maximum protection in the event of an accident and
reduce the risk of sustaining severe or fatal injuries only when they are
properly positioned. Furthermore, if the webbing is correctly positioned, the
seat belt will hold the occupants in the optimum position to ensure the air-
bag provides the utmost protection. The seat belt must therefore always be
worn and the webbing correctly positioned.
Incorrectly worn seat belts can cause severe or even fatal injuries
⇒  page 48, Adjusting the seat position.
Correct seat belt position
● The shoulder part of the seat belt must lie on the centre of the shoulder,
never across the neck or the arm, under the arm or behind the shoulder.
● The lap part of the seat belt must lie across the pelvis, never across the
stomach.
● The seat belt must lie flat and fit comfortably. Pull the seat belt tight if
necessary to take up any slack.
In the case of pregnant women , the seat belt must lie evenly across the
chest and as low as possible over the pelvis, never across the stomach.
Pregnant women must wear the seat belt properly at all times during the
pregnancy ⇒ Fig. 45. Adapting the position of the seat belt webbing to your size
The seat belt can be adapted using the following equipment:
●
Front seat height adjustment.
WARNING
An incorrectly worn seat belt web can cause severe injuries in the event
of an accident or sudden braking or manoeuvre.
● The seat belt cannot provide optimum protection if it is not correctly
worn and the backrest is not tilted slightly backwards.
● The seat belt itself or a loose seat belt can cause severe injuries if the
belt moves from hard areas of the body to soft areas (e.g. the stomach).
● The shoulder part of the seat belt must lie on the centre of the shoul-
der, never across the neck or the arm.
● The seat belt must lie flat and fit comfortably on the torso.
● The lap part of the seat belt must lie across the pelvis, never across
the stomach. The seat belt must lie flat and fit comfortably on the pelvis.
Pull the seat belt tight if necessary to take up any slack.
● Pregnant women must wear the lap part of the seat belt as low as
possible over the pelvis and always lie it flat, “surrounding” the stom-
ach.
● Do not twist the seat belt while it is fastened.
● Never pull the seat belt away from your body using your hand.
● Do not lie the seat belt across rigid or fragile objects, e.g. glasses,
pens or keys.
● Never use seat belt clips, retaining rings or similar instruments to al-
ter the position of the belt webbing. 

65
Ensuring you are correctly and safely seated
Note
If your physical constitution prevents you from maintaining the correct posi-
tion of the belt webbing, contact a Specialised workshop for help with any
special devices to ensure the optimum protection of the seat belt and air-
bag. SEAT recommends visiting a Technical Service. 
Automatic belt retainer, belt tension device, belt tension
limiter
Seat belts are part of the vehicle safety concept ⇒ page 67 and consist of
the following important functions:
Automatic belt retainer
Every seat belt is equipped with an automatic belt retainer on the shoulder
belt. If the belt is pulled slowly or during normal driving, the system allows
for total freedom of movement on the shoulder belt. However, during sud-
den braking, during travel in mountains or bends and during acceleration,
the automatic belt retainer on the seat belt is locked is pulled quickly.
Belt tension devices
The seat belts for the front occupants are equipped with belt tensioners.
Sensors will trigger the belt tension devices during severe head-on, lateral
and rear collisions and retract and tighten the seat belts. If the seat belt is
loose, it is retracted to reduce the forwards movement of occupants or
movement in the direction of the collision. The belt tension device works in
combination with the airbag system. The belt tension device will not be trig-
gered in the event of the vehicle overturning if the side airbags are not de-
ployed.
If the belt tension device is triggered, a fine dust is produced. This is normal
and it is not an indication of fire in the vehicle. Belt tension limiter
The belt tension limiter reduces the force of the seat belt on the body in the
event of an accident.
Note
The relevant safety requirements must be observed when the vehicle or
components of the system are scrapped. These requirements are known to
specialised workshops ⇒ page 65. 
Service and disposal of belt tension devices
If you work on the belt tension devices or remove and install other parts of
the vehicle when performing other repair work, the seat belt may be dam-
aged. The consequence may be that, in the event of an accident, the belt
tension devices function incorrectly or not at all.
Observe regulations so that the effectiveness of the belt tension device is
not reduced and that removed parts do not cause any injuries or environ-
mental pollution. These requirements are known to qualified dealerships.
WARNING
Improper handling and home-made repairs of seat belts, automatic belt
retainers and tension devices increase the risk of sustaining severe or fa-
tal injuries. The belt tension device may fail to trigger or may trigger in
the wrong circumstances.
● Never attempt to repair, adjust or remove or install parts of the belt
tension devices or seat belts. Any work must be performed by a special-
ised workshop only ⇒ page 222.
● Do not repair belt tension devices and automatic belt retainers. Re-
place them. 
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66Ensuring you are correctly and safely seated
For the sake of the environment
Airbag modules and belt tensioner may contain perchlorate. Observe the le-
gal requirements for their disposal. 

67
Ensuring you are correctly and safely seated
Airbag system Introduction
Front airbags have been installed for both driver and passenger. The front
airbags can also protect the chest and head of driver and passenger if the
seats, seat belts head restraints and, for the driver, the steering wheel are
correctly adjusted and used. Airbags are considered as additional safety
equipment. An airbag cannot replace the safety belt, which must be worn at
all times, even in front seats where front airbags have been installed.
Additional information and warnings:
● Driving tips ⇒ page 25
● Correct sitting position ⇒ page 48
● Seat belts ⇒ page 57
● Child seats (accessories) ⇒ page 76
● Care and cleaning of the vehicle interior ⇒ page 205
● Accessories, parts replacement, repairs and modifications ⇒ page 222
● Notes for the user ⇒ page 233
WARNING
Never exclusively trust the airbag system as a means of protection.
● Even when triggered, airbag protection is only auxiliary.
● The airbags provide the best protection when the seat belts are prop-
erly fastened, thus reducing the risk of sustaining injuries ⇒ page 57,
Seat belts.
● Before each trip, every occupant must sit properly, correctly fasten
the seat belt belonging to his or her seat and keeping it fastened
throughout the trip. This rule is valid for all occupants.
WARNING
Occupants sitting in the front of the vehicle must never carry any objects
in the deployment space between them and the airbags, as this increa-
ses the risk of sustaining injuries if the airbag is triggered. This modifies
the airbag deployment space or the objects may fly uncontrollably and
hit your body.
● Never carry objects in your hand or on your lap while the vehicle is in
motion.
● Never transport objects on the front passenger seat. In the event of
sudden braking and manoeuvres, the objects may end up in the airbag
deployment space and fly uncontrollably around the interior if the airbag
is activated.
● Occupants of the front and rear seats must never carry any other peo-
ple, pets or objects in the deployment space between them and the air-
bags. Make sure children and other passengers also respect this recom-
mendation.
WARNING
The airbag system provides protection for one accident only. If they have
been deployed, replace them.
● Ensure deployed airbags and the system components involved are im-
mediately replaced with new, SEAT-approved components for the vehicle.
● Have any repairs or modifications carried out at a Specialised work-
shop. Specialised workshops have the necessary tools, diagnostics
equipment, repair information and qualified personnel.
● Never fit recycled or reused airbag components in your vehicle.
● Never modify the airbag system components. 
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68Ensuring you are correctly and safely seated
WARNING
If the airbags are triggered, a fine dust is produced. This is normal and it
is not an indication of fire in the vehicle.
● This fine dust may irritate the skin and eyes and cause breathing dif-
ficulties, particularly in people suffering from or who have suffered from
asthma or other illnesses of the respiratory tract. To reduce breathing dif-
ficulties, get out of the vehicle and open and doors and windows to
breath in fresh air.
● Should you touch the dust, wash your hands and face using a mild
soap and water before you eat.
● Prevent the dust from affecting the eyes or open wounds.
● Rinse your eyes with water if you have dust in them.
WARNING
Solvents cause the surfaces of the airbag modules to become porous. If
an airbag is accidentally triggered, the detachment of plastic parts could
cause serious injury.
● Never clean the dash panel and the surfaces of the airbag modules
with cleaners containing solvents.
