main AUDI A4 2008 B8 / 4.G Owners Manual

Towing a trailer 232Towing a trailerDriving the vehicle with a trailer or
caravanTechnical requirements
The towing bracket must comply with certain technical
requirements.Your car is intended mainly for transporting passengers and
luggage. However, if suitably equipped, it can also be used to tow a
trailer or caravan.
If the car is supplied with a factory-fitted towing bracket it will
already have the necessary technical modifications and meet the
statutory requirements.
A 13-pin socket is provided to make the electrical connection
between the car and the trailer. If the trailer has a 7-pin plug you can
use an adapter cable. This is available from Audi dealers.
WARNING
If a towing bracket is retrofitted, the installation should be carried
out by a qualified workshop.•
In particular in high outside temperatures it is not possible to
drive up long steep gradients without a suitable cooling system.
The engine would then overheat.
•
Incorrect installation can result in a safety risk.
Points to check before towingTrailer weights
Never exceed the maximum permitted trailer weights ⇒page 323.If you do not load the trailer up to the maximum permitted trailer
weight, you can then climb correspondingly steeper gradients.
The maximum trailer weights listed are only applicable for altitudes
up to 1000 m above sea level. With increasing altitude the engine
power and therefore the car's climbing ability are impaired because
of the reduced air density, so the maximum trailer weight has to be
reduced accordingly. The weight of the car and trailer must be
reduced by 10% for every further 1000 m (or part thereof). This
figure refers to the combined weight of the (loaded) vehicle and
(loaded) trailer.
The figures for the draw bar weight that appear on the identification
plate of the towing bracket are for certification purposes only. The
correct figures for your specific vehicle, which may be lower than
these figures for the towing bracket, are given in the registration
documents. Also refer to ⇒page 323.
Distributing the load
Distribute loads in the trailer so that heavy objects are as near to the
axle as possible. Loads carried in the trailer must be secured to
prevent them slipping.
Where possible, operate the trailer with the maximum permitted
draw bar weight on the ball joint of the towing bracket, but do not
exceed the specified limit.
Tyre pressure
Check the tyre pressures on your car and adjust for “full load” condi-
tions (refer to the sticker listing the tyre pressures on the end face
of the driver's door). It may also be necessary to adjust the tyre pres-
sures on the trailer according to the recommendations of the trailer
manufacturer.
Exterior mirrors
Check whether you can see enough of the road behind the trailer
with the standard mirrors. If this is not the case you should have
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Towing a trailer233
Controls
Safety
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Technical data additional mirrors fitted. Both exterior mirrors should be mounted
on hinged extension brackets. Adjust the mirrors to give sufficient
vision to the rear.
Headlights
Before starting a journey, check the headlight beam settings with
the trailer hitched up. If necessary, alter the height of the headlight
beams by means of the headlight range control ⇒page 60.
Power supply
When you remove the ignition key the power supply to the trailer is
interrupted.
Removable ball joint coupling
Vehicles with a factory-fitted towing bracket are equipped with a
removable ball joint coupling. It is carried under the floor panel on
the left-hand side of the luggage compartment and is secured by a
strap.
Note
We recommend having the car serviced between the normal inspec-
tion intervals if it used frequently for towing a trailer.Applies to vehicles: with towing bracketTrailer stabilisation system
Trailer stabilisation helps to reduce the risk of the vehicle
skidding when towing a trailer.The trailer stabilisation system is operational only when the ESP is
switched on and there is no malfunction in the ESP ⇒page 17.
When is the trailer stabilisation system activated?
Trailer stabilisation is active when the following requirements are
met:•
The ESP must NOT be switched off ⇒page 222,
•
The trailer connector must be properly secured in the vehicle
socket.
•
Vehicle speed must be higher than approx. 60 km/h.
How trailer stabilisation works:
In many cases, the driver can stabilise a swaying trailer by manually
braking the vehicle.
However, if the ESP detects that the trailer is swaying and this is
affecting the towing vehicle, it will automatically brake the vehicle
to stabilise the trailer by slowing it down. The warning lamp
 will
light up in the instrument cluster. If possible, do not turn the
steering wheel at this stage.
In order to warn traffic behind you, the brake lights will come on
during this automatic braking operation.
A trailer weighing less than 70% of the kerb weight of the towing
vehicle may sway quite considerably without the trailer stabilisation
system intervening. This can happen when the swaying movements
of the light-weight trailer are not or hardly passed on to the towing
vehicle and are therefore not detected by the ESP.
If the system for activating the trailer brake lights is defective, this
will be indicated in the instrument cluster display ⇒page 37, “Bulb
monitor ”.
Requirements for correct functioning of the trailer
stabilisation system
If these conditions are not met in full, the trailer stabilisation system
will only intervene to a limited extent or not at all ⇒.
•
The electrical connection between the towing vehicle and the
trailer must be functioning correctly, without any defects.
•
The load on the trailer must be properly secured.
•
The tyre pressures on both the vehicle and the trailer must be
adapted to the load that is being carried.
•
Where possible, operate the trailer with the maximum permitted
draw bar weight.
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Towing a trailer235
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Technical data
Applies to vehicles: with towing bracketAccessories
Before mounting equipment and accessories (e.g. bicycle
rack) please observe the following notes.The equipment/accessories mounted must not protrude more than
700 mm from the ball joint .
The total weight (mounted equipment plus the load) must not
exceed 75 kg.
The maximum load depends on where the centre of gravity lies.
The maximum weight decreases as the distance between the centre
of gravity and the ball joint increases.
The following limits apply:
If the distance is 300 mm, the total weight (incl. the equipment
mounted) must not exceed 75 kg.
If the distance is 600 mm, the total weight (incl. the equipment
mounted) must not exceed 35 kg.
Only bicycle racks for a maximum of three bicycles may be used.
Equipment mounted on the towing bracket
We recommend that you only mount equipment (e.g. bicycle rack)
which has been approved by Audi on the ball joint. If you wish to
attach other equipment please make sure that it has been approved by the manufacturer for use on the ball joint. If you mount unsuit-
able equipment, this can cause damage to the towing bracket. In an
extreme case, damage to the towing bracket could cause it to break
⇒.
WARNING
•
If you wish to mount equipment which has not been approved
by Audi please ensure that it is suitable for use on Audi vehicles.
•
Use of unsuitable equipment can result in severe damage to
the towing bracket. The towing bracket could then break while
pulling a trailer and cause an accident.
•
Never use tools of any kind when fitting and removing the ball
joint. This could damage the mechanism which locks the ball joint
in place and impair its safety (accident risk).
Removable towing bracketApplies to vehicles: with removable towing bracketIntroduction
Special care is required when fitting and removing the
towing bracket.
Fig. 234 Load distribu-
tion of equipment and
accessories
A1A1
AAAB
Fig. 235 Luggage
compartment with
towing bracket
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– Also check the shaft section of the ball joint and its asso-
ciated mechanical parts to make sure they are clean and
undamaged.Continued ⇒page 237, “Fitting the ball joint (step 2)”.
WARNING
It is important to keep the mounting fixture clean. Otherwise the
ball joint may fail to engage securely (accident risk).Applies to vehicles: with removable towing bracketFitting the ball joint (step 2)The spring mechanism inside the ball joint must
be in the "ready" position.
– Check that the red marking ⇒fig. 238 on the knob is
inside the green zone on the ball joint.
– Check that the locking ball is inside the hole in the
shaft section of the ball joint.
– Check that the knob protrudes visibly from the ball joint,
so that there is a clear gap between the knob and the
ball joint.
The ball joint can only be installed if the internal spring mechanism
is in the ready position.
Continued ⇒page 237, “Fitting the ball joint (step 3)”.Applies to vehicles: with removable towing bracketFitting the ball joint (step 3)Setting the spring mechanism to the "ready"
position (if required)
– Insert the key ⇒fig. 239 for locking the ball joint into
the lock on the knob and turn it clockwise.
Fig. 238 Removable
towing bracket: Ball
joint
A2A1A3
Fig. 239 Removable
towing bracket:
Setting the spring
mechanism to the
"ready" positionFig. 240 Removable
towing bracket:
Inserting the ball joint
A4
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Towing a trailer239
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Technical data
– Check that the ball joint fits tightly in the mounting
fixture (try moving it about to check).
Electrical socket for trailer
– The cable of the towing bracket can be connected to the
socket ⇒page 238, fig. 242.If the safety check is not satisfactory, the ball joint must be fitted
again properly.
WARNING
To avoid accidents, the ball joint must meet all the safety require-
ments listed in the safety check. The towing bracket must not be
used if any one of these requirements is not met. If this is the case,
you should contact a qualified workshop.Applies to vehicles: with removable towing bracketRemoving the ball joint
– Take off the cover cap and insert the key ⇒fig. 243 in
the lock on the knob.
– Unlock the ball joint by turning the key clockwise.
– Take hold of the ball joint and pull out the knob in direc-
tion .
– Keep hold of the knob and turn it as far as it will go in
direction .
– Release the knob. The spring mechanism will remain in
the "ready" position ⇒.
– Pull the ball joint down out of the mounting fixture.
– Then swivel the socket up ⇒fig. 244 as far as it will go.
The mounting fixture will be closed automatically.
– Put away the ball joint attachment under the floor panel
in the luggage compartment.
WARNING
Make sure that the socket unit has closed off the mounting fixture
of the towing bracket properly. Otherwise the ball joint may fail to
engage securely if dirt accumulates in the mounting fixture.
Fig. 243 Removable
towing bracket:
Removing the ball joint
Fig. 244 Area below
rear bumper: Folding
up the socketA8
Aa
Ab
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Towing a trailer241
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Driving tips
General maintenance
Self-help
Technical data
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243 General maintenance
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Care of vehicle and cleaning 244Care of vehicle and cleaningGeneral notesRegular care helps to maintain the value of the vehicle.Regular and careful care helps to maintain the value of the vehicle.
This may also be one of the requirements for upholding any
warranty claims in the event of corrosion or paint defects.
Audi dealers and specialist retailers carry stocks of suitable car care
products. Please follow the instructions for use on the packaging.
WARNING
•
Cleaning products and other materials used for car care can
damage health if misused.
•
Car care products can contain toxic substances and must
always be kept in a safe place out of reach of children.For the sake of the environment
•
When purchasing car care products, try to select ones which are
not harmful to the environment.
•
Surplus cleaning materials should not be disposed of together
with ordinary household waste.
Care of exteriorWa s hi ng t he ve hi c l eThe longer substances like insects, bird droppings, resinous tree
sap, road dirt, industrial deposits, tar, soot or road salt and other
aggressive materials remain on the vehicle, the more damage they do to the paintwork. High temperatures (for instance in strong
sunlight) further intensify the corrosive effect.
After the period when salt is put on the roads it is important to have
the underside of the vehicle washed thoroughly.
Automatic car washes
Before going through a car wash, be sure to take the usual precau-
tions such as closing the windows and sunroof. If the vehicle has
special accessories such as spoilers or a roof carrier or two-way
radio aerial, etc., it is advisable to consult the car wash operator.
It is best to use a car wash without revolving bristles if possible.
Washing your car with a high-pressure cleaner
When cleaning the vehicle with a high-pressure cleaner, always
follow the operating instructions for the equipment. This applies
particularly to the operating pressure and the spraying distance. Do
not hold the spray nozzle too close to soft materials, such as rubber
hoses or seals.
Do not use a nozzle that sprays the water out in a direct stream or
one that has a rotating jet for forcing off dirt.
Washing the car by hand
When washing the car by hand, use plenty of water to soften the dirt
first, and rinse off as well as possible.
Then clean the vehicle with a soft sponge, glove or brush, using only
slight pressure. You should start on the roof and work down. Special
car shampoo should only be used for very persistent dirt.
Rinse the sponge or glove thoroughly and often.
Wheels, sills and similar should be cleaned last. Use a second
sponge for this.
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Care of vehicle and cleaning245
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WARNING
•
Do not wash the vehicle with the ignition switched on – risk of
accident.
•
Do not clean the underside of the car or inside the wheel arches
without protecting your hands and arms. You may cut yourself on
sharp metal parts.
•
Take care when washing the car during the winter: moisture
and ice on the brakes may affect braking efficiency – this could
cause an accident.Caution
•
Do not wash the vehicle in direct sunlight – otherwise the paint
can be damaged.
•
Do not use insect sponges or abrasive household sponges, etc.
– they can damage the surfaces.
•
The headlights should only be washed with water – do not wipe
them with a dry cloth or sponge. It is best to use soapy water.
•
Never wash tyres with a jet that sprays the water out in a direct
stream. This could damage the tyres – even if the spray is kept at a
distance and only used for a very short time.For the sake of the environment
The car should only be washed in special wash bays. This prevents
oily water from getting into the public drains. In some districts,
washing vehicles anywhere else may be prohibited.Waxing and polishingWaxing
Waxing protects the paintwork. It is time to apply a good coat of wax
when water no longer forms droplets and rolls off the clean paint-
work.Even if a wax solution is used regularly in the car wash, it is advis-
able to protect the paint with a coat of wax at least twice a year.
In the summer, you will find it is much easier to remove dead insects
(which accumulate on the bumper and the front of the bonnet) if the
car has been waxed recently.
Polishing
Polishing is only necessary if the paint has lost its shine, and the
gloss cannot be brought back by putting on wax.
The car must be waxed after polishing if the polish used does not
contain wax compounds to seal the paint.
Caution
Matt painted and plastic parts must not be treated with wax or
polish.Ornamental trim and mouldingsThe metal brightwork on the body is made of aluminium rather than
chrome (for environmental reasons).
Dirt or marks on the trim mouldings should be removed with an
acid-free cleaning agent (do not use a chrome cleaner). Body polish
is also unsuitable for use on trim mouldings. The intensive cleaning
fluids often used before the car goes into a car wash may contain
alkaline substances, which can cause dull or milky patches when
they dry out.
Audi dealers carry stocks of cleaning products which have been
tested for use on your vehicle and are not harmful to the
environment.
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Care of vehicle and cleaning 246Plastic partsPlastic parts will come clean with regular washing. If this is not suffi-
cient, plastic parts should only be treated with a special solvent-free
plastic cleaning agent. Do not use paint cleaners, polishes or wax on
plastic parts.Paint damageMinor damage to the paint, such as scratches or stone chips, should
be touched up without delay before the metal starts to corrode. Suit-
able touch-up brushes or sprays for your car can be obtained from
an Audi dealer.
The number of the original paint finish on the vehicle is given on the
data sticker ⇒page 321.
If corrosion is already visible it must be thoroughly removed by a
qualified workshop.Windows
Clear vision is an essential safety factor.The windscreen must not be cleaned with insect remover or wax,
otherwise the windscreen wipers will not function properly
(juddering).
Traces of rubber, oil, grease or silicone can be removed with a
window cleaning solution or a silicone remover. Wax residue can
only be removed with a special cleaner. Your Audi dealer will be able
to provide you with more detailed information.
The windows should also be cleaned on the inside at regular inter-
vals.
Use a separate cloth or chamois to dry the windows. Cloths used for
waxing and polishing contain residues that will cause smears on the
glass.
WARNING
Do not use water-repellent coatings on the windscreen. In bad visi-
bility conditions such as light rain, low sun or when driving at
night these coatings can cause increased dazzle, which is a
serious safety hazard. Such coatings can also cause the wiper
blades to judder.
Caution
•
Remove snow and ice from windows and mirrors with a plastic
scraper only. To avoid scratches caused by dirt on the glass, the
scraper should only be pushed in one direction and not moved to
and fro.
•
The heating element for the rear window is located on the inner
side of the window. To avoid damaging the heating element, do not
put stickers on the inner side of the window.
•
Never use warm or hot water to remove snow and ice from
windows and mirrors. This could cause the glass to crack!
Rubber seals (weatherstrips)The weatherstrips will remain pliable and last longer if they are
occasionally treated with a suitable care product (for example sili-
cone spray). This will also prevent premature ageing and leaks. The
doors will be easier to open as well. If they are kept pliable, the door
seals will be less likely to freeze up in the winter.WheelsThe wheels require regular attention to preserve their appearance.
It is important to remove road salt and brake dust by washing the
wheels at regular intervals, otherwise the finish will be impaired.
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