2008 AUDI A5 brake

Checking and topping up fluids 232Closing the bonnet– To close the bonnet, pull it down to overcome the spring
pressure.
– Then let it drop into the catches; do not press down ⇒.
WARNING
•
For safety reasons the bonnet must always be completely
closed when the vehicle is moving. After closing it always check
that it is properly secured. The bonnet must be flush with the adja-
cent body panels.
•
Should you notice that the bonnet is not safely secured when
the vehicle is moving, stop the vehicle immediately and close the
bonnet properly, otherwise it could cause an accident.
Engine compartment layoutEngine compartment layout
Main components for checking and refillingFig. 223 Typical locations of fluid containers, engine oil dipstick and engine oil
filler cap
Jump-start terminal (+) under a cover . . . . . . . . . . . . .
Brake fluid reservoir (
) . . . . . . . . . . . . . . . . . . . . . . . .
Engine oil filler cap (

) . . . . . . . . . . . . . . . . . . . . . . . .
Engine oil dipstick (orange) . . . . . . . . . . . . . . . . . . . . . .
Radiator expansion tank () . . . . . . . . . . . . . . . . . . . . .
Windscreen washer container (
) . . . . . . . . . . . . . . . .
Jump-start terminal (-) with hexagon head . . . . . . . . .
Hydraulic fluid reservoir for power steering . . . . . . . .
A1
241, 266
A2
238
A3
234
A4
234
A5
236
A6
242
A7
241, 266
A8
201
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Checking and topping up fluids 238Brake fluidChecking brake fluid level
The brake fluid level can be checked at a glance.– Check the fluid level on the brake fluid reservoir
⇒fig. 228. It should always be between the “MIN” and
“MAX” marks.In right-hand drive vehicles the brake fluid reservoir is on the other
side of the engine compartment.
The fluid level may drop slightly after a period of time due to the
automatic compensation for brake pad wear. This is quite normal.
However, if the level goes down noticeably in a short time, or drops
below the “MIN” mark, there may be a leak in the brake system. If
the fluid level in the reservoir is too low, this will be indicated by the
brake warning lamp ⇒page 31. If this should happen, take the car
to a qualified workshop immediately and have the brake system
inspected.
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.
Fig. 228 Engine
compartment: Mark-
ings on brake fluid
reservoir
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Checking and topping up fluids239
Controls
Safety
Driving tips
General maintenance
Self-help
Technical data
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 176.
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
engine.
Winter conditions
At low temperatures the battery has to work very hard. It also
provides only a fraction of the starting power it has at normal
temperatures.
For this reason, we recommend having the battery checked and
charged if necessary before the start of winter ⇒page 241.
WARNING
•
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-
sion).
•
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
damaged.
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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
document
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
2006.
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
225
Tyre width in mm
50
Height/width ratio in %
R
Tyre construction: Radial
17
Rim diameter in inches
94
Load rating code
Y
Speed rating code letter
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Wheels and tyres247
Controls
Safety
Driving tips
General maintenance
Self-help
Technical data replacement parts, trained personnel and facilities for disposing of
the old tyres.
WARNING
•
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
roads.
•
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
concerned.
Note
•
Never mount used tyres if you are not sure of their previous
history.
•
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.
Wheel bolts
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
your vehicle.
– 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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Self-help 258The TMS can be used at outside temperatures down to – 20 °C.
WARNING
After repairing a tyre please note the following points:•
Do not drive faster than 80 km/h.
•
Avoid heavy acceleration, hard braking and fast cornering.
•
Vehicle handling could be impaired.
•
Tyres which have been sealed using the TMS are only suitable
for temporary use. Damaged tyres must be renewed.
•
The TMS must NOT be used,
−on cuts and punctures larger than 4 mm
−if the wheel rim has been damaged
−if you have been driving with very low pressure or a
completely flat tyre
•
Seek professional assistance if the repair of a tyre puncture is
not possible with the sealing compound.
•
Do not allow the sealant to come into contact with your eyes,
skin or clothing.
•
If you do come into contact with the sealant immediately rinse
the eyes or skin affected with clean water.
•
Change clothing immediately if it becomes soiled with the tyre
sealant.
•
Make sure you do not breathe in the fumes!
•
If any of the tyre sealant is accidentally ingested, immediately
rinse the mouth thoroughly and drink lots of water.
•
Do not induce vomiting. Immediately contact a doctor!
•
If any allergic reactions should occur get medical help immedi-
ately.
•
Keep the sealant away from children.
For the sake of the environment
Used bottles of sealing compound can be returned to an Audi dealer
for disposal.
Note
•
If sealant should leak out, leave it to dry. When it has dried, you
can pull it off like a piece of foil.
•
Observe the expiry date stated on the sealing compound can.
Have the sealing compound exchanged by a qualified workshop.
Repairing a tyrePreparations
– If you have a flat tyre, stop the car well away from moving
traffic.
– Apply the parking brake to stop the vehicle moving acci-
dentally.
–Engage first gear (manual gearbox) or move selector
lever to position P (automatic gearbox).
Fig. 240 Repairing a
tyre
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Self-help 260•
Seek professional assistance if the repair of a tyre puncture is
not possible with the sealing compound.
•
If tyre pressure is less than 1.3 bar after driving about 10
minutes, the tyre is too badly damaged. Do not drive on. You
should obtain professional assistance.Caution
Take special care if you have to repair a tyre on a gradient.
Note
•
Do not use the compressor for longer than 6 minutes at a time,
as it could overheat. When the compressor has cooled down, you
can use it again.
•
If tyre sealant should leak out, leave it to dry and then pull it off
like foil.
•
After carrying out a tyre repair remember to buy a new tyre
sealant can at a qualified workshop. This will ensure that the Tyre
Mobility System is operative again.
•
Please observe the relevant regulations.
Changing a wheelPreparations
Some preparations are necessary before changing a
wheel.– If you have a flat tyre, stop the car well away from moving
traffic. Choose a location that is as level as possible.– All passengers should leave the car. They should wait in
a safe place (for instance behind the roadside crash
barrier).
– Apply the parking brake to stop the vehicle moving acci-
dentally.
–Engage first gear (manual gearbox) or move selector
lever to position P (automatic gearbox).
– When towing a trailer: unhitch the trailer from your
vehicle.
– Take the tools ⇒page 255 and the spare wheel*
⇒page 256 out of the luggage compartment.
WARNING
If you have a puncture in moving traffic, switch on the hazard
warning lights and place the warning triangle in a visible location.
This is for your own safety and also warns other road users.
Caution
If you have to change the tyre on a gradient, block the wheel oppo-
site the wheel being changed by placing a stone or similar object
under it to prevent the vehicle from rolling away.
Note
Please observe the relevant regulations.How to change a wheel
Change the wheel as described below.–Pull off the hub cap. Also refer to ⇒page 261, “Hub
caps”.
WARNING (continued)
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Self-help267
Controls
Safety
Driving tips
General maintenance
Self-help
Technical data terminal must not touch metal parts of the vehicle: this can cause
short circuiting.
•
Do not bend over the batteries – risk of acid burns.
•
The screw plugs on the battery cells must be screwed in firmly.
•
Keep sparks, flame and lighted cigarettes away from batteries:
the gases given off can cause an explosion.
•
If jump-starting another vehicle, position the jump leads in
such a way that they cannot come into contact with any moving
parts in the engine compartment of the other vehicle.Caution
Please note that the above method of connecting the leads is meant
for jump-starting your vehicle. If jump-starting another vehicle, you
should not connect the negative lead (–) to the negative terminal of
the discharged battery, but directly to the engine block or a solid
metal part bolted to the engine block. If the battery of the other
vehicle does not have a gas vent, there is a risk that a mixture of
oxygen and hydrogen gas can accumulate and cause an
explosion.Tow-starting and towing awayGeneral notes
Points to observe when tow-starting or towing awayIf you use a towrope:
Notes for the driver of the towing vehicle
– The towrope must be taut before driving off.– Engage the clutch very gently when starting to move; on
vehicles with automatic gearbox press the accelerator
slowly.
Notes for the driver of the towed vehicle
– The ignition should be switched on so that the turn
signals, horn, windscreen wipers and washers can be
used. Please ensure that the steering wheel is unlocked
when you switch on the ignition, and that it moves freely.
–Put gear lever in neutral (manual gearbox) or move
selector lever to position N (automatic gearbox).
– The brake servo and power steering only work when the
engine is running. Considerably more effort is required
on the brake pedal and steering wheel when the engine
is switched off.
– Ensure that the towrope remains taut at all times when
towing.
Towrope or towbar
It is easier and safer to tow a vehicle with a towbar. You should only
use a towrope if you do not have a towbar.
A towrope should be slightly elastic to reduce the loading on both
vehicles. It is advisable to use a towrope made of synthetic fibre or
similar material.
Attach the tow-rope or tow-bar only to the towing anchorages
intended for this purpose ⇒page 268 or ⇒page 269.
Driving technique
Towing requires some experience – especially when using a
towrope. Both drivers should be familiar with the technique required
for towing. Inexperienced drivers should not attempt to tow-start or
tow away another vehicle.
WARNING (continued)
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