ABS AUDI A4 2008 B8 / 4.G User Guide

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 correctly, the passengers benefit greatly
from the ability of the belts to reduce 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 every trip – even when driving
in town. This also applies to the 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 provide 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 correct position ⇒page 197, “How to wear seat belts
properly”. Ensure that the seat belts are worn exactly as recom-
mended in this chapter. Belts which are not worn properly can
increase the risk of injury in accidents considerably.
•
Do not allow the seat belt to become 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 dangerous 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 and 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 prevent the latch plate from engaging
properly.
•
The latch plate of the belt must always be engaged in the
correct buckle for that seat, otherwise the belt will not be fully
effective.
•
Check the condition of the seat belts at regular intervals. If you
notice that the belt webbing, fittings, retractor mechanism or buckle of any of the belts is damaged, the belt must be replaced
by a qualified workshop.
•
The seat belts must not be removed 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 generated 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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Airbag system203
Controls
Safety
Driving tips
General maintenance
Self-help
Technical data
Front airbagsDescription of front airbags
The airbag system is not a substitute for the seat belts.The front airbag for the driver is located in the padded hub of the
steering wheel ⇒fig. 214. The front airbag for the front passenger
is in the dashboard above the glove box ⇒fig. 215. The locations of
the airbags are marked with the word “AIRBAG”.
In conjunction with the three-point seat belts, the front airbags give
additional head and chest protection for the driver and front
passenger in the event of a severe frontal collision ⇒ in “Impor-
tant safety notes on the front airbag system” on page 204.
How the front airbags work
When fully inflated, the airbags reduce the risk of head or
chest injury.The airbag system is designed so that the airbags for the driver and
front passenger are triggered in a severe frontal collision.
In certain types of accident the front airbags, side airbags and one
of the head-protection airbags may be triggered together.
When the system is triggered, the airbags fill with a propellant gas
and open out in front of the driver and front passenger ⇒fig. 216.
In order to provide the desired extra protection in an accident, the
airbags have to inflate extremely rapidly (within fractions of a
second). The fully deployed airbags cushion the forwards move-
ment of the front occupants and help to reduce the risk of injury to
the head and the upper part of the body.
Special openings in the airbag allow the gas to escape at a
controlled rate to restrain the forward movement of the occupant's
head and torso. Once the impact has been absorbed, the airbag
deflates sufficiently for the front occupants to see forward.
Fig. 214 Driver's
airbag in steering
wheelFig. 215 Front
passenger's airbag in
dashboard
Fig. 216 Front airbags
in inflated condition
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Intelligent technology 222Intelligent technologyElectronic stabilisation program (ESP)DescriptionESP increases the car's stability. It reduces the tendency to skid and
improves the stability and roadholding of the vehicle. ESP detects
critical handling situations, such as understeer, oversteer and
wheelspin on the driven wheels. It stabilises the vehicle by braking
individual wheels or by reducing the engine torque. The warning
lamp
 in the instrument cluster starts flashing as soon as the ESP
intervenes.
The ESP incorporates the functions of the anti-lock brake system
(ABS), the traction control system (ASR), the electronic differential
lock (EDL) and the dynamic steering*.
Anti-lock brake system (ABS)
ABS prevents the wheels from locking up under braking until the
vehicle has reached a virtual standstill. You can continue to steer the
vehicle even when the brakes are on full. Keep your foot on the brake
pedal and do not pump the brakes. You will feel the brake pedal
pulsate while the anti-lock brake system is working.
Brake assist system
The brake assist system can speed up the braking process and
shorten the braking distance. It automatically boosts the braking
force if you press the brake pedal quickly in an emergency. On vehi-
cles with adaptive cruise control*, the brake assist system will build
up a small amount of pressure in the hydraulic brake system if it
senses that you are too close to the vehicle in front.
Traction control system (ASR)
In the event of wheelspin, the traction control system reduces the
engine torque to match the amount of grip available. This helps the
car to start moving, accelerate or climb a gradient.Electronic differential lock (EDL)
When the EDL detects wheelspin, it brakes the spinning wheel and
directs the power to the other driven wheel (or wheels on quattro*
versions). This function is active up to about 100 km/h.
To prevent the disc brake of the braked wheel from overheating, the
EDL cuts out automatically if subjected to excessive loads. The
vehicle can still be driven. The EDL will switch on again automati-
cally when the brake has cooled down.
Dynamic steering*
On vehicles with dynamic steering*, the ESP can also intervene in
the steering to stabilise the vehicle in critical situations.
WARNING
•
The grip provided by the ESP, ABS, ASR, EDL and dynamic
steering* systems is still subject to the physical limits of adhesion.
Always bear this in mind, especially on wet or slippery roads. If
you notice the systems cutting in, you should reduce your speed
immediately to suit the road and traffic conditions. Do not let the
extra safety provided tempt you into taking any risks when driving
– this can cause accidents.
•
Please remember that the accident risk always increases if you
drive fast, especially in corners or on a slippery road, or if you
follow too close behind the vehicle in front of you. Please bear in
mind that even ESP, ABS, brake assist, EDL, ASR and dynamic
steering* cannot compensate for the increased accident risk.
•
When accelerating on a uniformly slippery surface (for instance
all four wheels on ice or snow), press the accelerator gradually and
carefully. The driven wheels may otherwise start to spin (in spite
of the integrated control systems), which would impair the car's
stability and could lead to an accident.
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Intelligent technology223
Controls
Safety
Driving tips
General maintenance
Self-help
Technical data
Note
•
To ensure that the ASR works properly, all four wheels must be
fitted with identical tyres. Any differences in the rolling radius of the
tyres can cause the system to reduce engine power when this is not
desired.
•
Should a malfunction occur in the ABS or EDL, both the ABS
warning lamp
 and the ESP warning lamp
 ⇒page 19 will light
up.
•
In the event of a malfunction in the ESP system, the warning
lamp  ⇒page 17 will light up.
•
If a malfunction should occur in the ABS, the ESP, EDL and ASR
will also be out of action.
•
The systems can make noises when they intervene.
Switching on and off
The ESP is switched on automatically when the engine is
started.
Switching off the traction control system (ASR)
In particular circumstances, it may be advisable to switch off the
traction control system (ASR) to allow a certain amount of wheel
slip. For example:•
Rocking the car backwards and forwards to free it
•
Driving in deep snow or on loose surfaces
•
Driving with snow chains
Press the button briefly ⇒fig. 232 or ⇒fig. 233. The
warning lamp
 will light up and the message ASR off will appear
in the driver information system display.
The traction control system (ASR) can only be switched off at speeds
below 50 km/h on vehicles with front-wheel drive. At 70 km/h it will
switch on again automatically. The ASR can be deactivated at any
speed on vehicles with four-wheel drive.
Switching off the ESP
Press the button for longer than 3 seconds. The ESP
warning lamp  will light up and the message ESP switched off will
appear in the display. The ASR is also deactivated when the ESP is
switched off.
Switching on
Press the button again. The message ESP/ASR on will
appear briefly on the display.
Fig. 232 Version A:
Centre console
(bottom), ESP OFF
button
Fig. 233 Version B:
Centre console (top),
ESP OFF button
ESP OFFESP OFFESP OFF
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Care of vehicle and cleaning247
Controls
Safety
Driving tips
General maintenance
Self-help
Technical data After washing, the wheels should only be cleaned with an "acid-
free" cleaning agent for alloy wheels. This is available from Audi
dealers and specialist retailers. Never leave the cleaning agent on
the rims for any longer than specified in the instructions before
rinsing it off. If the wheel cleaner fluid contains acid it can attack the
surfaces of the wheel bolts.
Car polish or other abrasive agents should not be used. If the
protective paint coating is damaged by stone chips etc., the
damaged area should be touched up immediately.
WARNING
Please note when cleaning the wheels that water, ice and road salt
can impair the effectiveness of the brakes – this can cause an
accident.Care of interiorSound system / MMI* display screen and MMI control console*The display screen can be cleaned with a soft cloth and a special
“LCD cleaner” (available from retailers of electrical goods). Moisten
the cloth with a small amount of the cleaning fluid.
Clean the MMI control console with a fine brush first to prevent any
dirt from getting in between the control buttons and the housing.
We then recommend wiping the MMI control console using a cloth
moistened with washing-up liquid and water.
Caution
To avoid scratching the screen, do not wipe the display with a dry
cloth.
•
To avoid any possibility of damage, do not let any liquid get
inside the control console.
Plastic parts and leatherettePlastic parts and leatherette can be cleaned with a damp cloth. If
this is not sufficient, plastic parts and leatherette should only be
treated with a special solvent-free plastic cleaner.Textile covers and trim partsTextile covers and trim parts (e.g. seats, door trim) should be
cleaned regularly with a vacuum cleaner. This will remove surface
dirt which could otherwise be rubbed into the textile material
during use. Do not use steam cleaners, as the steam could carry the
dirt deeper into the textile material.
Normal cleaning
We recommend that you use a soft sponge or lint-free, micro-fibre
cloth for normal cleaning. Only use brushes on floor coverings and
mats, as other textile surfaces could become damaged.
In the case of normal surface dirt you can use a foam cleaner. Use a
sponge to spread the foam on the textile surface and to work it into
the material lightly. However, make sure that the textile material
does not become soaking wet. Then dab off the foam with a dry and
absorbent cloth (e.g. a micro-fibre cloth) and vacuum off any
residue once the surface is completely dry.
Removal of stains
To treat stains caused by spilled drinks (coffee, fruit juice or similar)
make up a solution with a mild detergent for sensitive fabrics and
apply it with a sponge. If the stains are difficult to remove, a
washing paste can be applied directly onto the stain and worked
into the fabric. The surface will then have to be wiped with clear
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Care of vehicle and cleaning 248water to remove any residue left by the paste. To do so, use a damp
cloth or sponge and then dab the stain with an absorbent cloth.
Treat chocolate or make-up stains with a washing paste and then
rinse off with water (using a damp sponge).
A spirit-based cleaner can be used to remove grease, oil, lipstick or
ball point pen. Then dab the dissolved grease or colour particles off
with an absorbent cloth or similar. You may also have to treat the
stain once more using washing paste and water.
If the covers or textile trim panels are badly soiled we recommend
that you have them cleaned by a professional cleaning company.
Note
Please make sure you close any velcro fasteners on your clothing, as
these could otherwise damage the upholstery.Applies to vehicles: with leather upholsteryNatural leather
Audi does everything possible to preserve the special
qualities of leather as a natural product.General notes
We have a wide selection of leathers. The main type used is nappa
in various forms, that is leather with a smooth surface in a selection
of colours.
The amount of dye used determines the appearance and properties
of leather. If the leather is left in a more natural state, it retains its
typical natural appearance and is pleasant and comfortable for the
seat occupants. Fine veins, healed scars, insect bites, wrinkles and
a subtle variation in shading remain visible; these are the character-
istic features of genuine natural leather.
Natural napped leather does not have a protective surface coating
of dye. It is therefore somewhat more prone to damage. You should bear this in mind if children or pets often travel in the car, or if there
are other factors that could lead to damage.
Types of leather with a coloured surface coating are likely to be
more resistant to damage. This has a great advantage for day-to-day
use. However, this means that the typical natural characteristics of
the surface are less apparent, though this does not affect quality.
Cleaning and care
Because of the natural properties of the specially selected hides
employed, the finished leather has a certain sensitivity to grease
and dirt, etc. so a degree of care is required in everyday use and
when looking after the leather. Dark clothing (especially if damp or
incorrectly dyed) may stain leather upholstery. Dust and grit in the
pores and seams can have an abrasive effect and damage the
surface of the leather. Therefore leather should be cleaned at
regular intervals, depending on the actual amount of use. When
they have been in use for a certain time, your car seats will acquire
a typical and distinctive patina. This is characteristic for real leather
upholstery, and is a sign of genuine quality.
To maintain the value of natural leather you should note the
following points:
Caution
•
Avoid exposing leather to direct sunlight for long periods, other-
wise it may tend to lose some of its colour. If the car is left for a
prolonged period in the bright sun, it is best to cover the leather.
•
Sharp-edged objects on clothing, such as belts, zip fasteners,
rivets or similar, can also leave permanent scratches and rough
marks on the surface of the leather.Note
•
Use a suitable impregnating cream with ultra-violet protection at
regular intervals and after cleaning. This cream will nourish and
moisturise the leather, keep it supple and able to breathe. In addi-
tion, it will also help to protect the surface of the leather.
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Care of vehicle and cleaning249
Controls
Safety
Driving tips
General maintenance
Self-help
Technical data
•
Clean the leather every 2 to 3 months and remove fresh dirt as
necessary.
•
Remove stains from fresh ball-pen and other inks, lipstick, shoe
cream and similar stains as soon as possible.
•
Preserve the colour of the leather. A special coloured cream will
renew the colour of the leather when required and will eliminate
differences in colour.
Applies to vehicles: with leather upholsteryCleaning and care of leather upholstery
Natural leather requires an extra degree of attention and
care.Normal cleaning
– Moisten a cotton or woollen cloth with water and wipe
over the leather surfaces.
More stubborn dirt
– More stubborn dirt can be removed using a mild soap
solution (pure liquid soap: two tablespoons dissolved in
one litre of water).
– It is very important not to let the water soak through the
leather or penetrate into the seams.
– Then wipe off with a soft, dry cloth.
Removal of stains
– Remove fresh water-based stains such as coffee, tea,
juices, blood etc. with an absorbent cloth or kitchen roll,
dried-on stains with the cleaning agent from the care set.– Remove fresh fat-based stains on the surface such as
butter, mayonnaise, chocolate, etc. with an absorbent
cloth or kitchen roll or with the cleaning agent from the
care set.
–Treat fat-based, dried-in stains with grease-dissolving
spray.
–Treat less common stains such as ball-pen and other
inks, felt-tip pens, nail polish, dispersion paint, shoe
cream etc. with a special leather stain remover.
Leather care products
– The leather should be treated regularly (about twice a
year) with a special leather-care product.
– Apply the cream very sparingly.
– Then wipe off with a soft, dry cloth.
Should you have any questions regarding the care and cleaning of
the leather upholstery in your vehicle, we recommend that you
contact your Audi dealer. The staff there will gladly provide you with
further information on cleaning and care of your upholstery and on
our complete range of leather care products:•
Cleaning and care set
•
Coloured leather-care cream
•
Stain remover for ball-pen inks, shoe cream etc.
•
Grease dissolving spray
•
New products and further developmentsCaution
On no account use solvents (such as petrol, turpentine), wax polish,
shoe cream or similar materials.
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Checking and topping up fluids263
Controls
Safety
Driving tips
General maintenance
Self-help
Technical data
Changing brake fluid
When required, the brake fluid should be changed by a
competent mechanic with the proper equipment.Brake fluid gradually absorbs moisture from the atmosphere. If the
water content in the brake fluid is too high, this may cause corrosion
in the brake system over time. In addition, the boiling point of the
brake fluid will be considerably reduced. This could adversely affect
the braking ability in certain circumstances.
For this reason the brake fluid must be changed periodically.
Your vehicle's Service Schedule will tell you when the brake fluid has
to be changed.
It is advisable to have the brake fluid changed as part of a regular
Inspection Service at your Audi workshop. They are familiar with the
procedure and have the necessary special tools and spare parts as
well as the proper facilities for disposing of the old fluid.
Use only the genuine brake fluid specified by the factory Qualified
workshops know that the brake fluid “DOT 4” is approved by Audi.
The brake fluid must be fresh and unused.
WARNING
•
Brake fluid is poisonous; store it in the sealed original container
in a safe place out of reach of children.
•
Heavy use of the brakes may cause a vapour lock if the brake
fluid is left in the system for too long. This would seriously affect
the efficiency of the brakes and the safety of the car – risk of acci-
dent.Caution
Please note that brake fluid will attack the paintwork on contact.
For the sake of the environment
If the fluid has to be drained out of the brake system, use an appro-
priate container to catch the used brake fluid and dispose of it in the
proper manner.BatteryGeneral notes
All work on batteries requires specialist knowledge.The battery is virtually maintenance-free. It is checked as part of the
Inspection Service.
We recommend that you replace a battery once it is older than 5
years.
When an airbag is triggered, the battery will, under certain circum-
stances, be disconnected from the on-board power supply for
safety reasons ⇒ in “General notes on airbag system” on
page 201.
Disconnecting the battery
If the battery is disconnected, some of the vehicle's functions will
become inoperative (e.g. electric windows). These functions will
require resetting after the battery is reconnected. For this reason,
the battery should only be disconnected from the vehicle's electrical
system when absolutely necessary.
If the vehicle is not used for long periods
If you do not drive your vehicle for a period of several days or weeks,
the power management will gradually shut off the on-board
systems one by one, or reduce the amount of current they are using.
This limits the amount of power consumed and helps to ensure reli-
able starting even after a long period ⇒page 226.
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