2008 AUDI A4 warning

Checking and topping up fluids 262
WARNING
•
The cooling system is under pressure. Do not unscrew the cap
on the expansion tank when the engine is hot: you could be
scalded by escaping steam
•
The coolant and coolant additive can be a health hazard. Store
the coolant additive in the original container in a safe place out of
reach of children – risk of poisoning.For the sake of the environment
Drained off coolant should not be used again. Drain off the used
coolant into a suitable container and dispose of it in the proper
manner (observe environmental regulations).Radiator fan
The radiator fan can start running spontaneously.The radiator fan is driven by the engine via a poly V-belt. The speed
of the fan is varied by a viscous clutch according to the temperature.
There is also an auxiliary electric fan, which cuts in automatically
whenever the temperature of the coolant and the engine compart-
ment rises above a certain level.
The auxiliary fan can continue to run for as long as 10 minutes after
stopping the engine – even after the ignition is switched off. It may
also start running suddenly ⇒ after a while if•
residual heat raises the coolant temperature, or
•
the hot engine compartment is additionally heated up by the
sun.
WARNING
When working in the engine compartment be aware that the radi-
ator fan may start running suddenly – risk of injury.
Brake fluidChecking brake fluid level
The brake fluid level can be checked at a glance.– Check the fluid level on the brake fluid reservoir
⇒fig. 258. 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 32. If this should happen, take the car
to a qualified workshop immediately and have the brake system
inspected.
Fig. 258 Engine
compartment: Mark-
ings on brake fluid
reservoir
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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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Checking and topping up fluids 264Please 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 265.
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.
Important 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
compartment.
WARNING
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

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
acid.
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Checking and topping up fluids265
Controls
Safety
Driving tips
General maintenance
Self-help
Technical data charges) when handling cables and electrical equipment. Never
cross the battery poles. The resulting high-energy sparks can
cause injury.
•
A highly explosive mixture of gases is given off when the
battery is under charge. Only charge battery in a well ventilated
area.
•
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
battery.
•
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.
•
Do not expose the battery to direct sunlight over a long period of
time, as the intense ultraviolet radiation can affect the battery
housing.
•
If the car is left standing for long periods, protect the battery
from extreme cold temperature so that it does not “freeze up” and
become damaged.
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 264 and ⇒.
– Switch off all electrical equipment. Remove the ignition
key.
– Open the bonnet ⇒page 254.
– Open the red cap on the positive terminal ⇒fig. 259.
– Follow the correct procedure for connecting the charger
cables to the jump-start terminals (terminal with red cap
= “positive”, terminal with hexagon = “negative”).
WARNING (continued)
Fig. 259 Engine
compartment: Termi-
nals for jump leads and
battery charger
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Checking and topping up fluids 266
– Now connect the battery charger to the mains and switch
on.
– 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 256.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.
WARNING
Never charge a frozen battery – it could explode.
Note
Use only the terminals in the engine compartment to charge the
battery.
Replacing 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 226.
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).
Caution
•
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 264, “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
could escape.
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Wheels and tyres269
Controls
Safety
Driving tips
General maintenance
Self-help
Technical data
– 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 268, fig. 261.
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
road wheels.
Driving habits
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
Audi dealer.
WARNING
•
Always adapt the tyre pressure accordingly when the vehicle
load changes.
•
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 tyres 270Tread 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. 262 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.
WARNING
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
rear axles.
•
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. 263. 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
tread pattern.
– If possible, tyres should be replaced at least in pairs and
not individually (i.e. both front tyres or both rear tyres
together).
Fig. 262 Tyre tread:
Tr e a d w e a r i n d i c a t o r s
WARNING (continued)
Fig. 263 Changing
wheels round
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Wheels and tyres 272replacement 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 292.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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