AUDI A5 2008 8T / 1.G Owners Manual
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Checking and topping up fluids239
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
We recommend that you replace a battery once it is older than 5
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
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 202.Please note that certain convenience features, such as the Audi
advanced key*, the remote control key or the electrical seat adjust-
ment may not be available when you unlock the vehicle. These func-
tions will be restored when you switch on the ignition and start the
At low temperatures the battery has to work very hard. It also
provides only a fraction of the starting power it has at normal
For this reason, we recommend having the battery checked and
charged if necessary before the start of winter ⇒page 241.
All work on batteries requires specialist knowledge. For queries
regarding the vehicle battery please contact an Audi dealership or
other qualified workshop (risk of chemical burns / risk of explo-
The battery must not be opened. Do not attempt to make any
changes to the electrolyte level of the battery. Otherwise, there is
a risk that a mixture of oxygen and hydrogen gas can accumulate
and cause an explosion.Note
If the vehicle is to be left standing for a period of several weeks at
extremely low temperatures, the battery should be removed from
the vehicle. This ensures that it cannot “freeze up” and be
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Checking and topping up fluids 240Important safety warnings for handling a car battery
All work on batteries requires specialist knowledge.The vehicle battery is located under the floor panel in the luggage
Always be aware of the danger of injury and chemical burns as
well as the risk of accident or fire when working on the battery and
the electrical system.•
Wear safety glasses. Do not allow acid or lead particles to come
into contact with eyes, skin or clothing.
Battery acid is extremely corrosive. Wear protective gloves and
safety glasses. Do not tilt the battery - acid can leak out of the
vapour vent. If electrolyte should splash into the eyes rinse at once
for several minutes using clear water. Then seek medical care
immediately. Neutralize any acid splashes on the skin or clothing
with soap solution, and rinse off with plenty of water. If acid is
swallowed by mistake, consult a doctor immediately.
Keep open flames, sparks, uncovered lights and lit cigarettes
away from battery. Avoid sparks (including those from static charges) when handling cables and electrical equipment. Never
cross the battery poles. The resulting high-energy sparks can
A highly explosive mixture of gases is given off when the
battery is under charge. Only charge battery in a well ventilated
Keep children away from the battery and battery acid.
Switch off all electrical equipment before starting any work on
the vehicle electrical system. Remove the ignition key. The minus
cable of the battery must be disconnected. When changing a light
bulb, it is sufficient to only turn off the light.
Before disconnecting the battery, turn off the anti-theft
system! Otherwise, the alarm will sound.
When disconnecting the battery from the vehicle's electrical
system, first disconnect the minus cable and then the plus cable.
Before reconnecting the battery, turn off all electrical equip-
ment. First connect the plus cable, then the minus cable. The
battery cables must not be connected to the wrong battery poles
- serious risk of cable fire.
Never charge a frozen or thawed out battery - risk of explosion
and chemical burns! A battery must be replaced once it has been
frozen. When it is discharged the battery can freeze at tempera-
tures around 0°C.
Make sure that the vapour hose is always attached to the
Never use a damaged battery - risk of explosion! Replace a
damaged battery immediately.Caution
Never disconnect the car's battery with the engine running or
with the ignition turned on, otherwise the electrical system or elec-
trical components will be damaged.
Wear safety glasses!
Battery acid is extremely corrosive. Wear protec-
tive gloves and safety glasses.
Keep open flames, sparks, uncovered lights and
lit cigarettes away from battery!
A highly explosive mixture of gases is given off
when the battery is under charge!
Keep children away from the battery and battery
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Checking and topping up fluids241
Do not expose the battery to direct sunlight over a long period of
time, as the intense ultraviolet radiation can affect the battery
If the car is left standing for long periods, protect the battery
from extreme cold temperature so that it does not “freeze up” and
Charging the battery
Terminals for charging the battery are fitted in the engine
compartment.– Note the warnings ⇒ in “Important safety warnings
for handling a car battery” on page 240 and ⇒.
– Switch off all electrical equipment. Remove the ignition
– Open the bonnet ⇒page 230.
– Open the red cap on the positive terminal ⇒fig. 229.
– Follow the correct procedure for connecting the charger
cables to the jump-start terminals (terminal with red cap
= “positive”, terminal with hexagon = “negative”).– Now connect the battery charger to the mains and switch
– After charging the battery: switch off the battery charger
and disconnect the mains cable.
– Now disconnect the charger cables.
– Refit the red cap onto the positive terminal.
– Close the bonnet ⇒page 232.
When it is discharged the battery can freeze at temperatures
around 0°C. A frozen battery must be thawed before charging ⇒.
However, it is advisable to replace the battery if it has frozen,
because the ice can crack the battery casing and allow the battery
acid to escape.
Charging the battery
Important: Before you charge the battery make sure you read the
manufacturer's instructions for using the battery charger.
When charging with a low current (for instance with a small battery
charger) the battery does not have to be disconnected. The battery
must not be opened while you are charging it.
Fast-charging the battery
For technical reasons it is not permissible to fast-charge the battery
using charging devices with an output voltage higher than 14.8 V.
Never charge a frozen battery – it could explode.
Use only the terminals in the engine compartment to charge the
Fig. 229 Engine
nals for jump leads and
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Checking and topping up fluids 242Replacing the battery
A replacement battery must have the same specifications
as the original equipment battery.Your vehicle is equipped with an intelligent power management
system to control the distribution of electrical energy ⇒page 202.
The power management function ensures that the battery is
charged much more efficiently than on vehicles without a power
management system. For this additional power to be available after
replacing the battery, we recommend that the replacement battery
used is of the same make and type as the original-equipment
battery. The battery must be encoded in the control unit for power
management. This has to be done by a qualified workshop.
A replacement battery must have the same capacity, voltage (12 V)
and current rating. It must also have the same dimensions as the
original, factory-fitted battery and have sealed caps. The battery
must comply with the standards TL 825 06 (dated December 1997 or
later) and VW 7 50 73 (August 2001 or later).
Make sure that the vent hose is always attached to the opening
on the side of the battery. Gases or battery acid can otherwise
escape and possibly cause damage.
The battery holder and clamps must always be correctly secured.
Before starting any work on the battery, always observe the
warnings listed under ⇒page 240, “Important safety warnings for
handling a car battery”.For the sake of the environment
Batteries contain toxic substances including sulphuric acid and
lead. They must be disposed of appropriately and must not be put
together with ordinary household waste. Make sure the battery
removed from the vehicle cannot tip over. Otherwise, sulphuric acid
Windscreen washerPlain water on its own is not sufficient for the windscreen
washer system.The container for the windscreen washer
contains the cleaning
fluid for the windscreen and the headlight washer system*
⇒fig. 230. Container capacity: ⇒page 293.
Plain water on its own is not enough to clean the glass properly. It
is therefore advisable to add a suitable washer fluid additive (with
wax solvent) to the water. A washer fluid with freeze-resistant addi-
tive should be used in winter.
Never put in radiator anti-freeze or other additives.
Never use washer fluid which contains paint thinners or solvents
as it can damage the paintwork.
Fig. 230 Engine
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Wheels and tyres243
Wheels and tyresWheelsGeneral notes–When driving with new tyres, be especially careful during
the first 500 km.
– If you have to drive over a kerb or similar obstacle, drive
very slowly and as near as possible at a right angle to the
– Inspect the tyres regularly for damage (cuts, cracks or
blisters, etc.). Remove any foreign bodies embedded in
– Damaged wheels and tyres must be replaced immedi-
– Keep grease, oil and fuel off the tyres.
– Replace any missing valve caps as soon as possible.
– Mark the wheels before taking them off so that they
rotate in the same direction when put back.
– When removed, the wheels or tyres should be stored in a
cool, dry and preferably dark place.New tyres
New tyres do not give maximum grip straight away and should
therefore be “run in” by driving carefully and at moderate speeds for
about the first 500 km. This will also help to make the tyres last
The tread depth of new tyres may vary, according to the type and
make of tyre and the tread pattern.Concealed damage
Damage to tyres and rims is often not readily visible. If you notice
unusual vibration or the car pulling to one side, this may indicate
that one of the tyres is damaged. Reduce speed immediately if there
is any reason to suspect that damage may have occurred. Inspect
the tyres for damage. If no external damage is visible, drive slowly
and carefully to the nearest qualified workshop and have the car
Tyres with directional tread pattern
An arrow on the tyre sidewall indicates the direction of rotation on
tyres with directional tread. Always note the direction of rotation
indicated when mounting the wheel. This guarantees optimum grip
and helps to avoid aquaplaning, excessive noise and wear.
Tyre service life
Correct inflation pressures and sensible driving habits
will increase the service life of your tyres.– Check the tyre pressures at least once a month.
Fig. 231 Open driver's
door (LHD vehicle) with
sticker listing tyre
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Wheels and tyres 244
– The tyre pressures should only be checked when the
tyres are cold. The slightly raised pressures of warm tyres
must not be reduced.
– The pressures must be altered to suit major changes in
the load being carried.
– Avoid fast cornering and hard acceleration.
– Inspect the tyres for irregular wear from time to time.Tyre pressure and vehicle loading
The tyre pressure must be adjusted according to the load the vehicle
is carrying. We recommend adhering to the tyre pressure specifica-
tions for a maximum load. The tyre inflation pressures are listed on
a sticker on the end face of the driver's door ⇒page 243, fig. 231.
However, if you prefer an extra-smooth ride and the vehicle is not
fully loaded, you can select the tyre pressure for a normal load (no
more than three people travelling in the vehicle). However, should
you wish to drive with a full load you must increase the tyre pressure
to the specified maximum.
Under-inflation or over-inflation will reduce the life of the tyres
considerably and also impair the car's handling. Correct inflation
pressures are very important, especially at high speeds. The pres-
sures should therefore be checked at least once a month and before
starting a journey.
Do not forget the spare wheel* when checking the tyre pressures.
Keep the spare tyre inflated to the highest pressure required for the
Fast cornering, heavy acceleration and hard braking (squealing
tyres) all increase tyre wear.Wheel balancing
The wheels on new vehicles are balanced. However, various factors
encountered in normal driving can cause them to become unbal-
anced, which results in steering vibration.
Unbalanced wheels should be rebalanced, as they otherwise cause
excessive wear on steering, suspension and tyres. A wheel must
also be rebalanced when a new tyre is fitted or if a tyre is repaired.
Incorrect wheel alignment
Incorrect wheel alignment causes excessive tyre wear, impairing the
safety of the vehicle. If you notice excessive tyre wear, contact your
Always adapt the tyre pressure accordingly when the vehicle
Under-inflated tyres flex more and can overheat at continuous
high speeds. This can cause tread separation and tyre blow-out,
which could result in an accident.For the sake of the environment
Under-inflated tyres will increase the fuel consumption.
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Wheels and tyres245
Tread wear indicators
The tread wear indicators show the condition of the tyre
treads.The original tyres on your vehicle have 1.6 mm high “tread wear
indicators” ⇒fig. 232 running across the tread. Depending on the
make, there will be 6 to 8 of them spaced at equal distances around
the tyre. Markings on the tyre sidewall (for instance the letters “TWI”
or a triangle) indicate the positions of the tread wear indicators.
The minimum tread depth required by law in Germany is 1.6 mm
(measured in the tread grooves next to the tread wear indicators).
Other specifications may apply in export countries.
To avoid putting safety at risk, the tyres must be replaced at the
latest when the tread is worn down to the tread wear indicators.•
Especially in difficult driving conditions such as wet or icy
roads, it is important that the tyres have sufficient tread depth.
The tread depth should same on the tyres of both the front and the
The decrease in driving safety due to insufficient tread depth is
particularly evident in vehicle handling, when there is a risk of aquaplaning in deep puddles of water and when driving through
corners. Braking is also adversely affected.
The speed has to be adapted accordingly, otherwise there is a
risk of losing control over the vehicle.
Changing wheels roundTo ensure that the wear is equal on all tyres the wheels should be
changed round from time to time according to the system
⇒fig. 233. All the tyres will then last for about the same time.Replacing wheels and tyres
It is important to use the correct wheels and tyres when
replacement is necessary.– All four wheels must be fitted with tyres of the same type,
size (rolling circumference) and preferably the same
– If possible, tyres should be replaced at least in pairs and
not individually (i.e. both front tyres or both rear tyres
Fig. 232 Tyre tread:
Tr e a d w e a r i n d i c a t o r s
Fig. 233 Changing
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Wheels and tyres 246
– Never use tyres whose actual size exceeds the dimen-
sions of the factory-approved makes of tyre.
– If you wish to fit the vehicle with non-standard rims or
tyres, it is advisable to consult an Audi dealer before
purchasing them.The tyres and wheel rims are an essential part of the vehicle's
design. The tyres and rims approved by Audi are specially matched
to the characteristics of the vehicle and make a major contribution
to good roadholding and safe handling ⇒.
The sizes of the rims and tyres approved for your vehicle are listed
in the vehicle's documents (e.g. EC Certificate of Conformity or COC
5)). The vehicle documents vary depending on the
country of residence.
Understanding the tyre designations makes it easier to choose the
correct tyres. For example, radial ply tyres have the following tyre
designations marked on the sidewall:
225 / 50 R 17 94 Y
This contains the following information:
The manufacturing date is also indicated on the tyre sidewall
(possibly only on the inner side of the wheel):
DOT ... 1006...means, for example, that the tyre was produced in the 10th week of
Please note that with some types of tyres, the actual tyre size can
differ from the nominal size marked on the tyre (for instance 225/50
R 17 94 Y), and there may be significant differences in the contours
of the tyres, even though the tyres are marked with the same
nominal size designation. When replacing the tyres, it is therefore
important to make sure that the actual size of the new tyres does
not exceed the dimensions of the factory-approved makes of tyre.
Failure to observe this requirement can affect the clearance needed
for the tyres. This could result in contact between the tyres and
suspension components or bodywork. The brake lines could also be
damaged and the vehicle's safety could be severely impaired ⇒.
When using tyres with the maximum permitted nominal dimen-
sions, this can also void the vehicle's registration.
If you use tyres that are approved by Audi you can be sure that the
actual tyre dimensions will be correct for your vehicle. If you decide
to fit a different type of tyre, you must obtain the appropriate manu-
facturer's certificate from the tyre retailer to confirm that the tyres
are suitable for your vehicle. Keep this certificate in a safe place.
Your local Audi dealer will be able to advise you on which tyres may
be fitted to your vehicle.
On vehicles with four-wheel drive, all four tyres must always be
fitted with tyres of the same type, make and tread pattern, as other-
wise the driveline can be damaged by continuous variations in the
wheel speeds. For the same reason, only use a spare wheel* with
the same tyre dimensions as the normal road wheels.
It the spare tyre* is not the same type as the tyres fitted on the car
(for example if the car has winter tyres or wide-section tyres) you
should only use the spare tyre if a puncture occurs, and then only
for a short period of time. In this case, please drive with extra care.
Refit the normal road wheel as soon as possible.
It is best to have all servicing of wheels and tyres performed by a
qualified workshop. They have the necessary special tools and
5)COC = certificate of conformity
Tyre width in mm
Height/width ratio in %
Tyre construction: Radial
Rim diameter in inches
Load rating code
Speed rating code letter
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Wheels and tyres247
Technical data replacement parts, trained personnel and facilities for disposing of
the old tyres.
It is very important to ensure that the tyres you have chosen
have adequate clearance. When selecting replacement tyres, do
not rely entirely on the nominal tyre size marked on the tyre; with
some makes of tyre the effective tyre size can differ significantly
from the nominal dimensions, even though the tyres have the
same size designation. Inadequate tyre clearance can result in
damage to the tyres or the vehicle, causing a serious safety risk. It
may also invalidate the vehicle's type approval for use on public
Please ask your Audi dealer or qualified workshop whether run
flat tyres can be used on your vehicle. Unauthorised use of these
tyres can invalidate the vehicle's type approval for use on public
roads. Furthermore, this could cause damage to your vehicle and
possibly also result in an accident.
Avoid running the car on tyres that are more than 6 years old.
If you have no alternative, you should drive slowly and with extra
care at all times.For the sake of the environment
Old tyres must be disposed of according to the laws in the country
Never mount used tyres if you are not sure of their previous
For technical reasons it is not normally possible to use wheel
rims from other vehicles. In some cases this also applies to rims
from other vehicles of the same model.
The wheel bolts are designed to suit the rims on your car.The wheel bolts are matched to the rims. When installing different
wheels (for instance wheels with winter tyres) it is important to use
the correct wheel bolts with the right length and correctly shaped
bolt heads. This is essential for the secure fit of the wheels and for
the proper function of the brake system.
Audi dealers have full information on the technical requirements
when installing or changing tyres, rims or wheel trims.
The wheel bolts should be clean and turn easily.
A special adapter is required to turn the anti-theft wheel bolts*
⇒page 264.Winter tyres
Winter tyres will significantly improve the car's handling
in winter road conditions.–Use only radial ply winter tyres.
– Winter tyres must be fitted on all four wheels.
– Only use winter tyres of the correct type approved for
– Please note that the maximum permissible speed for
winter tyres may be lower than for summer tyres.
– Also note that winter tyres are no longer effective when
the tread is worn down.
– After fitting the wheels you must always check the tyre
pressures. The correct tyre pressures are listed on the
sticker on the end face of the driver's door.
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Wheels and tyres 248In winter road conditions winter tyres will considerably improve the
car's handling. Due to their type of construction (width, rubber
compound, tread pattern), summer tyres give less grip on ice and
snow. This applies particularly to vehicles equipped with wide
section tyres or high speed tyres (code letters H, V or Y on the side-
Only use winter tyres of the correct type approved for your vehicle.
The sizes of the winter tyres approved for your vehicle are listed in
the vehicle's documents (e.g. EC Certificate of Conformity or COC
6)). The vehicle documents vary depending on the
country of residence. Also refer to ⇒page 245.
Winter tyres are no longer fully effective when the tread is worn
down to a depth of 4 mm.
The performance of winter tyres is also severely impaired by ageing,
even if the tread is still much deeper than 4 mm.
Winter tyres are subject to the following maximum speed limits
according to speed rating code letter: ⇒
In Germany vehicles capable of exceeding these speeds must have
an appropriate sticker attached so it is visible to the driver. Suitable
stickers are available from Audi dealers and specialist retailers.
Please note regulations to this effect in your country.“All-weather” tyres can also be used instead of winter tyres.
Using winter tyres with V-rating
Please note that the generally applicable 240 km/h speed rating for
winter tyres with the letter "V" is subject to technical restrictions;
the maximum permissible speed for your vehicle may be signifi-
cantly lower. The maximum speed limit for tyres with a V-rating
depends directly on the maximum axle weights for your car and on
the listed weight rating of the tyres being used.
It is best to contact an Audi dealer to check the maximum speed
which is permissible for the V-rated tyres fitted on your car on the
basis of this information.
Exceeding the maximum speed permitted for the winter tyres
fitted on your car can cause tyre failure, resulting in a loss of
control of the vehicle – risk of accident.
For the sake of the environment
Summer tyres should be fitted again as soon as possible; they give
better handling on roads which are free of snow and ice. Summer
tyres produce less rolling noise, do not wear down as quickly and,
most importantly, reduce fuel consumption.Snow chains
Snow chains will improve the vehicle's handling on snow-
covered roads.– Snow chains can be used on the front wheels only.
– Keep your speed below 50 km/h.Snow chains will improve braking ability as well as traction in winter
6)COC = certificate of conformitySpeed rating code letter
Maximum speed limit
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