AUDI A4 2008 B8 / 4.G Owners Manual
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Checking and topping up fluids259
Applies to vehicles: without oil dipstickChecking the oil level (without dipstick)
You can check the engine oil level via the sound system or
MMI*.– Select: Function selector button > Oil level.
– Park your vehicle on a level surface.
– Allow the warm engine to run briefly at idling speed and
then switch off the ignition.
– Wait approx. 2 minutes.
– Read off the oil level on the display ⇒fig. 255. Top up the
engine oil if the bar in the oil level display is near the
“min” mark ⇒page 259.Depending on how you drive and the conditions in which the car is
used, oil consumption can be up to 0.5 ltr./1000 km. Oil consump-
tion is likely to be higher for the first 5000 km.
The oil level display is intended solely for information purposes. An
oil level warning will appear in the instrument cluster if the oil level
is too low. Add more oil ⇒page 259. If the bonnet has been opened, the current oil level will be shown in the instrument cluster the next
time the ignition is switched on.
Topping up the engine oil
from oil filler opening ⇒fig. 256.
– Carefully put in the specified grade of oil ⇒page 323
0.5 litres at a time.
– Check the oil level again after two minutes by calling up
the sound system or MMI* display or using the oil
dipstick ⇒page 258.
– If the oil level is too low, add more engine oil.
– Replace the oil filler cap carefully and push the dipstick
all the way in (on vehicles with dipstick).
Ensure that no oil comes into contact with hot engine compo-
nents when topping up: this could cause a fire.
Wash your skin thoroughly if it comes into contact with engine
Fig. 255 Display: Oil
Fig. 256 Engine
oil filler cap
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Checking and topping up fluids 260
The oil level must never be above area ⇒page 258, fig. 254,
as this may result in damage to the catalytic converter or to the
engine. On vehicles without an oil dipstick, you can check the oil
level via the sound system or MMI*. Contact a qualified workshop to
extract the engine oil if necessary.
No additives should be used with engine oil. Any damage caused
by the use of such additives would not be covered by the factory
warranty.For the sake of the environment
Never pour oil down drains or into the ground.
Always observe statutory requirements when disposing of
empty oil canisters.
The purpose of the coolant is to carry heat away from the
engine. The correct amount of anti-freeze is important to
prevent the cooling system from freezing in winter.The cooling system is filled for life at the factory, so the coolant does
not need to be changed. The coolant consists of a mixture of water
and anti-freeze additive G12++. This is a glycol-based anti-freeze
with anti-corrosion additives.
The amount of anti-freeze additive required depends on the temper-
atures to be expected in the winter season. If the anti-freeze concen-
tration is too low the coolant can freeze, resulting in failure of the
cooling system and heater.The cooling system is filled at the factory with the correct amount of
anti-freeze for the country concerned.
In most cases the mixture consists of 60% water and 40% additive.
This mixture gives the required anti-freeze protection at tempera-
tures down to -25 °C and protects the alloy parts of the cooling
system against corrosion. It also prevents scaling and raises the
boiling point of the coolant.
Countries with warm climate
The coolant concentration must not be reduced by adding plain
water, even in the summer or in warm climates. The concentration
of the anti-freeze additive must always be at least 40%.
Countries with cold climate
If greater anti-freeze protection is required in very cold climates, the
proportion of the anti-freeze additive G12++ can be increased. A
concentration of 60% offers protection down to about - 40 °C. The
concentration of the anti-freeze additive must not be more than
60%, otherwise this would reduce the anti-freeze protection. In addi-
tion, the cooling effect will be adversely affected.
Vehicles for export to countries with a cold climate (such as Sweden,
Norway and Finland) are supplied with antifreeze protection down
to about -35 °C. The concentration of the antifreeze additive for
these countries should always be at least 50%.
It is advisable to have the cooling system checked before the
winter season to make sure that the antifreeze concentration is
adequate for the conditions to be expected. This applies particularly
if you intend to take the car into a colder climate zone. If necessary,
have the anti-freeze concentration increased to 50 - 60% as required.
Use only anti-freeze additive G12++, an additive meeting the
specification “TL 774 G”. Other additives may give considerably
inferior corrosion protection. The resulting corrosion in the cooling
system can lead to a loss of coolant, causing serious damage to the
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Checking and topping up fluids261
The coolant additive G12++ can be mixed only with additives
G12+ and G12.
Checking coolant level
The coolant level can be checked at a glance.– Switch off the ignition.
– Read off coolant level on radiator expansion tank
⇒fig. 257. When the engine is cold it should be between
the “MIN” and “MAX” marks. When the engine is hot it
may be slightly above the “MAX” mark.The coolant level should be checked with the engine switched off.
The coolant level is monitored by a warning lamp in the instrument
cluster ⇒page 33. However, we recommend that it should be
Any loss of coolant normally indicates a leak in the cooling system.
In this case the cooling system should be inspected by a qualified
workshop without delay. It is not sufficient merely to top up the
coolant.If there are no leaks in the system, a loss of coolant can only occur
if the coolant boils and is forced out of the system as a result of
Radiator sealants must not be added to the coolant. Such additives
could seriously impair the function of the cooling system.Topping up the coolant
Be careful when topping up coolant.– Switch off the engine.
– Wait for the engine to cool down.
– Cover the cap on the expansion tank ⇒fig. 257 with a
cloth, and carefully unscrew the cap anti-clockwise
– Add coolant.
– Screw the cap on again tightly.Make sure that the coolant meets the required specifications
⇒page 260, “Coolant”. Do not use a different type of additive if anti-
freeze additive G12++, G12+ or G12 is not available. In this case use
only water and bring the coolant concentration back up to the
correct level as soon as possible by putting in the specified additive.
Always top up with fresh, unused coolant.
Do not fill above the “MAX” mark. Excess coolant is forced out of the
system through the valve in the filler cap when the engine gets hot.
If a lot of coolant has been lost, wait for the engine to cool down
before putting in cold coolant. Failure to do so could result in
serious engine damage.
Fig. 257 Engine
ings on radiator expan-
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Checking and topping up fluids 262
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
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
Fig. 258 Engine
ings on brake fluid
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Checking and topping up fluids263
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.
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-
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
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 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
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 265.
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
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
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
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Checking and topping up fluids265
Technical data 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.
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 264 and ⇒.
– Switch off all electrical equipment. Remove the ignition
– 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”).
Fig. 259 Engine
nals for jump leads and
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Checking and topping up fluids 266
– 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 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.
Never charge a frozen battery – it could explode.
Use only the terminals in the engine compartment to charge the
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).
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
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Checking and topping up fluids267
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. 260. Container capacity: ⇒page 321.
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. 260 Engine
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Wheels and tyres 268Wheels 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. 261 Open driver's
door (LHD vehicle) with
sticker listing tyre
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