2008 AUDI S4 ron

Seat belts
194Seat beltsWhy is it so important to use seat
belts?Seat belts provide effective protection
The common belief that passengers can brace their
weight with their hands in a minor collision is false.It is an established fact that seat belts provide good protection in
accidents. Therefore wearing a seat belt is required by law in most
countries.
Properly worn seat belts hold the occupants in the best position for
maximum protection ⇒fig. 203. The seat belts are capable of
absorbing much of the kinetic energy arising in a collision. Also they
help to prevent uncontrolled movements which could lead to severe
injuries ⇒page 195, “Important safety instructions for using seat
belts”.
If they wear the seat belts correc tly, the passengers benefit greatly
from the ability of the belts to re duce the kinetic energy gradually.
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 forces acting on the occupants and consequently the risk of
injury.
Although these examples are based on
a frontal collision, the phys-
ical principles involved are the same in other types of accidents and
for vehicles with an airbag system. This is why it is so important to
put on the seat belts before every trip – even when “just driving
around the corner”. Ensure that your passengers wear their seat
belts as well ⇒.
Properly worn seat belts have been shown to be an effective means
of reducing the potential for injury and improving the chances of
survival in a serious accident ⇒page 195, “Forces acting in a colli-
sion”.
For information on how children can travel safely in the car
⇒ page 210, “Points to remember if children are travelling in the
car”.
WARNING
•
Seat belts must be put on before ev ery trip – even when driving
in town. This also applies to th e rear passengers (injury risk).
•
During pregnancy, women should always ensure they wear a
seat belt. The best way to protect the unborn child is to protect the
mother ⇒page 198, “Wearing and adjusting the seat belts during
pregnancy”.
Fig. 203 Driver
protected by the prop-
erly worn seat belt
during a sudden brake
manoeuvre
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Seat belts195
Controls
Safety
Driving tips
General maintenance
Self-help
Technical data
Important safety instructions for using seat belts
There are a number of safety points concerning the seat
belts which you should remember. This will help to reduce
the risk of injury in an accident.
WARNING
•
The seat belts can only provi de maximum protection if the
seats are adjusted properly ⇒page 73, “Seats and storage”.
•
To ensure proper protection, it is important to wear the seat
belts in the co rrect position ⇒page 197, “How to wear seat belts
properly”. Ensure that the seat belts are worn exactly as recom-
mended in this chapter. Belts wh ich are not worn properly can
increase the risk of injury in accidents considerably.
•
Do not allow the seat belt to be come twisted or jammed, or to
rub on any sharp edges.
•
Never allow two passengers (even children) to share the same
seat belt. It is especially dangerou s to place a seat belt over a child
sitting on your lap.
•
Do not wear the belt over hard or fragile objects (such as
glasses or pens, etc. ) because this can cause injuries.
•
Loose, bulky clothing (such as an overcoat over a jacket)
impairs the proper fit an d function of the belts.
•
The belts must be kept clean, otherwise the retractors may not
work properly ⇒page 250, “Seat belts”.
•
The slot in the seat belt buckle must not be blocked with paper
or other objects, as this can prev ent the latch plate from engaging
properly.
•
The latch plate of the belt mu st always be engaged in the
correct buckle for that seat, ot herwise the belt will not be fully
effective.
•
Check the condition of the seat bel ts at regular intervals. If you
notice that the belt webbing, fi ttings, retractor mechanism or buckle of any of the belts is da
maged, the belt must be replaced
by a qualified workshop.
•
The seat belts must not be remov ed or modified in any way. Do
not attempt to repair a damaged belt yourself.
•
Seat belts which have been worn in an accident and stretched
must be replaced by a qualified workshop. The belt anchorages
should also be checked.
Forces acting in a collisionThe physical principles involved in a frontal impact
Very large forces are generat ed during a collision; these
forces have to be absorbed.
WARNING (continued)
Fig. 204 Passengers of
a vehicle which is
headed for a brick wall.
They are not using seat
belts.
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Seat belts
196The physical principles involved in a frontal collision are relatively
simple:
Both the moving vehicle and the passengers possess energy, which
is known as “kinetic energy” ⇒ page 195, fig. 204. The amount of
“kinetic energy” depends on the speed of the vehicle and the weight
of the vehicle and passengers. The higher the speed and the greater
the weight, 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 to 50 km/h, for example, the kinetic
energy increases by a factor of four. Because these passengers are
not restrained by seat belts, the entire amount of kinetic energy has
to be absorbed at the point of impact ⇒fig. 205. This would result
in serious or potentially fatal injury.
Even at urban speeds of 30 km/h to 50 km/h, the forces acting on the
occupants in a collision can reach the equivalent of 1 ton (1000 kg)
or more. At greater speed these forces are even higher. A rule of
thumb: if the speed doubles, the forces increase by a factor of four.
Passengers who do not wear seat belts are not “attached” to the
vehicle. In a frontal collision they will continue to move forward at
the speed their car was travelling just before the impact.
What happens to passengers not wearing seat belts?
Passengers not wearing seat belts risk fatal injuries in the
event of an accident.In a frontal collision, unbelted passengers will be thrown forwards
and make violent contact with the steering wheel, dashboard, wind-
screen, etc ⇒ fig. 206. Passengers not wearing their belts risk being
thrown out of the car, resulting in potentially fatal injuries.
The common belief that occupants can brace their weight with their
hands in a minor collision is false. Even at low speeds the forces
acting on the body in a collision are so great that it is not possible
to hold yourself in the seat.
Fig. 205 The vehicle
crashes against the
wall
Fig. 206 A driver not
wearing a seat belt can
be thrown forwardsFig. 207 A rear
passenger not wearing
a seat belt can be
thrown forwards
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Seat belts197
Controls
Safety
Driving tips
General maintenance
Self-help
Technical data
It is also important for the rear passengers to wear seat belts, as
they could otherwise be thrown forwards violently in an accident.
Rear passengers who do not use seat belts endanger not only them-
selves but also the other occupants
⇒page 196, fig. 207.
How to wear seat belts properlyPutting on the three-point seat belts
Always fasten your seat belts before driving off.– Adjust the front seat and head restraint correctly before
putting on the seat belt ⇒page 73, “Seats and storage”. – To fasten the belt, take hold of the latch plate and pull it
slowly across your chest and lap ⇒.
– Insert the latch plate into the buckle for the appropriate seat and push it down until it is securely locked with an
audible click ⇒fig. 209.
– Pull the belt to check that it is now securely fastened.
The three-point inertia reel belts are tensioned automatically. The
retractor system gives complete freedom of movement, as long as
the pull on the belt is slow. Hard braking locks the belt. The belt will
also lock when you accelerate, drive up or down a steep hill or in a
sharp curve.
WARNING
•
Always make certain that the belt is positioned properly
⇒ fig. 208 – risk of injury ⇒page 197, “Adjusting the seat belts”.
•
The latch plate of the belt must always be engaged in the
correct buckle for that seat. Oth erwise the belt will not be fully
effective and the danger of injury increases.
Adjusting the seat belts
Always position seat belts properly for maximum safety.
Fig. 208 Positioning of
head restraints and
seat beltsFig. 209 Driver's seat:
Belt buckle and latch
plate
Fig. 210 Adjusting
shoulder and lap belt
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Seat belts
198The height of the front seat on your vehicle can be adjusted in order
to match the position of the seat belt to your height.
WARNING
•
The diagonal part of the belt s hould never be positioned across
the neck, but roughly over the centre of the shoulder; it should fit
closely against the upper part of the body. The lap part of the belt
must be worn tightly across the hips, and not over the abdomen
⇒ page 197, fig. 210. Pull the belt tight if necessary to take up any
slack.
•
Always make sure that belt is positioned properly. Incorrectly
worn seat belts can give rise to injuries even in a minor collision.
•
Seat belts worn too loose can re sult in injuries because they
allow excessive forward movement in a crash; the occupant will
be brought to a sudden stop by the belt webbing.
Wearing and adjusting the seat belts during pregnancy
To afford the best protection for the unborn child it is
important for the mother to wear the seat belt properly at
all times.
Women should always ensure they adjust the seat belt
correctly during pregnancy.
– Adjust the front seat and head restraint correctly before putting on the seat belt ⇒page 73, “Seats and storage”.
– To fasten the belt, take hold of the latch plate and pull it slowly down across your chest. Wear the lap portion of
the seat belt as low as possible over the hips so that there
is no pressure on the stomach ⇒fig. 211, ⇒.
– Insert the latch plate into the buckle for the appropriate seat and push it down until it is securely locked with an
audible click ⇒page 197, fig. 209.
– Pull the belt to check that it is now securely fastened.
WARNING
During pregnancy, women should especially make sure to wear
the lap portion of the seat belt as low as possible across the hips
so that there is no pressure on the stomach.
Fig. 211 Positioning
seat belts during preg-
nancy
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Seat belts199
Controls
Safety
Driving tips
General maintenance
Self-help
Technical data
Applies to vehicles:Seat belt height adjustment
Seat belt height adjusters can be used to adjust the height
of the shoulder portion of the seat belt.– Take hold of the guide fitting and slide it up ⇒ fig. 212 ,
or
– Compress the adjuster and slide the guide fitting
downwards .
– After adjusting, pull the shoulder belt sharply to check that the catch on the guide fitting is engaged securely.
Note•
The shoulder portion of the seat belt must be positioned roughly
midway over the shoulder – it must never rest against the neck
⇒ in “Adjusting the seat belts” on page 197.
•
It is also possible to adjust the he ight of the front seats to obtain
the best position for the front seat belts.
Taking off the seat belts
The red button releases the belt from the buckle.– Press the red button in the seat belt buckle ⇒fig. 213.
The latch plate will spring out of the buckle.
– Guide the belt back by hand so that it is taken up by the retractor.Belt tensionersHow the belt tensioners work
The seat belts for the driver and front passenger are
equipped with belt tensioners.The seat belts on the front seats are tensioned automatically in
frontal, side and rear-end impacts above a certain degree of
severity. This helps to reduce the forward motion of the occupants.
In a less severe accident, or in the event of a roll-over, the belt
tensioners are not activated.
Fig. 212 Belt height
adjustment for the
front seats: guide
fitting
A2
A1
A2
Fig. 213 The latch
plate of the belt
springs out of the
buckle
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Airbag system201
Controls
Safety
Driving tips
General maintenance
Self-help
Technical data
Airbag systemDescription of airbag systemGeneral notes on airbag system
The airbag is an integral part of the car's passive safety
system.In conjunction with the three-poin t seat belts, the airbag system
gives the front occupants additional protection for the head and
chest in the event of a severe frontal collision.
In a severe side collision the side airbags and the head-protection
airbags reduce the risk of injury to the occupants in the areas of the
body facing the impact ⇒.
In addition to their no rmal function of protecting the occupants in a
collision, the seat belts also hold them in a position where the
airbags can inflate properly and provide maximum protection.
The airbag system will only work with the ignition on. The airbag
system is monitored electronically; the airbag warning lamp indi-
cates whether the system is functioning properly.
The main parts of the airbag system are:•
the electronic monitoring system (control unit and sensors),
•
the two front airbags,
•
the front side airbags, the side ai rbags on the outer rear seats*
and the head-protection airbags,
•
the airbag warning lamp in the instrument cluster.
There is a fault in the airbag system if the warning
lamp
•
does not come on when the ignition is switched on,
•
does not go out about 4 seconds after the ignition is switched
on,
•
goes out and then comes on again after the ignition is switched
on,
•
comes on or flickers while the car is moving.
WARNING
•
The airbags are not a substitute for the seat belts; they are an
integral part of the car's overall passive safety system. The airbags
can only offer effective protection if the occupants are wearing
their seat belts. For this reason it is very important to wear the
seat belts at all times ⇒page 194, “Why is it so important to use
seat belts?”.
•
The seat belts and airbags can only provide maximum protec-
tion if the occupants are seated correctly ⇒page 73, “Seats and
storage”.
•
If you do not wear a seat belt, if you lean forward, or are not
seated correctly while the vehicle is in motion, you are at greater
risk of injury should the airbag system be triggered in an accident.
•
Components of the airbag system are located in various parts
of the vehicle. If repairs to other vehicle components make it
necessary to perform work on the airbag system or to remove or
install parts of the airbag system, this may cause damage to the
airbag system. As a result, the ai rbags may not inflate correctly or
may not be triggered at all in an a ccident situation. For this reason,
you should always have the work carried out by a qualified work-
shop.
•
If a fault should occur in the airbag system, have the system
checked immediately by a qualified workshop. Otherwise the
system may fail to trigger in an accident.
•
Do not attempt to modify compon ents of the airbag system in
any way.
•
Never make any alterations to the front bumper or the body.
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Airbag system
202•
Do not remove the front seats.
•
The airbag system can only be ac tivated once; if the airbag has
been triggered, the system must be replaced. Should the airbag
system or airbag modules have to be replaced, the qualified work-
shop carrying out the replacement will document all details in the
appropriate section of the Service Schedule.
•
If you sell the vehicle, please remember to pass on the
complete Service Wallet to the new owner. If any of the airbags
have been deactivated, it is impo rtant that the new owner is also
given the relevant documents.
•
The relevant safety requirements must be observed when the
vehicle or components of the airbag or belt tensioner systems are
scrapped.
•
In an accident in which one or more airbags are triggered the
alternator and the starter are - for safety reasons - both discon-
nected from the battery via a pyrotechnic circuit breaker.
−Any repairs to the pyrotechnic circuit breaker must always
be performed by a qualified workshop (accident risk).
− The relevant safety requirements must be observed when
the vehicle or the circ uit breaker are scrapped.
When are the airbags triggered?
The airbag system is triggere d in collisions with a severe
impact.The airbag system is designed so that the airbags for the driver and
front passenger are triggered in a severe frontal collision.
In severe side collisions the side airbags on the impact side of the
vehicle are triggered together with the head-protection airbag.
The front airbags, side airbags and one of the head-protection
airbags may be triggered together in certain types of accident. The airbag system is
not triggered in minor frontal or side collisions,
or in rear collisions or if the car overturns. In these situations the
occupants are protected by wearing the seat belts.
Factors determining the triggering response
It is not possible to define the exact triggering response of the
airbag system in all possible situat ions, since the circumstances in
different types of accident will va ry considerably. Important factors
include, for example, the nature (hard or soft) of the object which
the car hits, the angle of impact, vehicle speed and so on.
Whether the airbags are triggered depends primarily on the vehicle
deceleration rate resulting from the collision. By processing the
signals from the sensors located in the vehicle, the electronic
control unit is immediately able to evaluate the severity of the colli-
sion and activate the restraint systems accordingly. If the decelera-
tion rate is below the predefined reference value in the control unit
the airbags will not be triggered, even though the accident may
cause extensive damage to the car.
Note
The airbag releases a fine dust when it inflates. This is quite normal
and does not mean there is a fire in the vehicle.
WARNING (continued)
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