2008 AUDI A4 main

Intelligent technology 228With the engine switched off
If you listen to the radio or use the other MMI functions when the
engine is not running, this will discharge the battery.
The MMI display will show this warning message before the battery
power drops to a level where the starting ability is impaired.
Please start engine, otherwise system will switch off
in 3 minutes.
This message warns you that the system you are using will be
switched off automatically after 3 minutes. You should therefore
start the engine if you wish to continue using the system.
When the engine is running
Although the alternator generates electrical power, the battery can
still become discharged while the vehicle is being driven. This can
occur when a lot of power is being consumed but only a small
amount supplied, especially if the battery is not fully charged
initially.
To restore the necessary energy balance, the system will then
temporarily shut off the electrical components that are using a lot
of power, or reduce the current they are consuming. Heating
systems in particular use a large amount of electrical power. If you
notice, for instance, that the seat heating* or the rear window
heater is not working, they may have been temporarily switched off
or regulated to a lower heat output. These systems will be available
again as soon as sufficient electrical power is available.
You may also notice that the engine runs at a slightly faster idling
speed. This is quite normal, and no cause for concern. The increased
idling speed allows the alternator to meet the greater power
requirement and charge the battery at the same time.
Driver message in the instrument cluster displayIf battery power drops to a level at which you may encounter prob-
lems when starting the engine, the following message will appear
in the instrument cluster display:
 Low battery charge: Battery will be charged while driving
This message reminds you that the starting reliability may be
impaired. The message will disappear as soon as you set off and the
battery is charged.
Message comes on and goes out again
If the message appears in the display after the ignition is switched
on or while driving, and goes out again after a period of time, the
battery has been charged up again sufficiently while the vehicle was
being driven.
Message comes on and does not go out
If the message appears in the display after the ignition is switched
on or while driving, and does not go out again, the battery is not
being maintained at the proper power level. Starting reliability may
be impaired. You should have the battery checked by a qualified
workshop as soon as possible.
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Your vehicle and the environment229
Controls
Safety
Driving tips
General maintenance
Self-help
Technical data
Your vehicle and the environmentRunning inA new vehicle should be run in over a distance of 1,500 km. For the
first 1,000 km the engine speed should not exceed 2/3 of the
maximum permissible engine speed – do not use full throttle and do
not tow a trailer or caravan. From 1,000 to 1,500 km you can gradu-
ally increase the engine rpm and road speed.
During its first few hours of running, the internal friction in the
engine is greater than later on when all the moving parts have
bedded down.
How the vehicle is driven for the first 1,500 km also influences the
engine quality. After the first 1,500 km you should continue driving
at moderate engine speeds, in particular when the engine is cold.
This helps to reduce wear and tear on the engine and increases the
potential mileage which can be covered by the engine.
You should also avoid driving with the engine speed too low.
Change down to a lower gear when the engine no longer runs
“smoothly”. Excessively high engine speeds are prevented by an
automatic rev limiter.Emission control systemsCatalytic converter
Applies to vehicles with petrol engine: The vehicle must only be
used with unleaded petrol, otherwise the catalytic converter will be
destroyed.
Never run the tank completely dry. The irregular fuel supply can
cause misfiring, which would allow unburnt fuel to enter the
exhaust system, which could cause overheating and damage the
catalytic converter.Diesel particulate filter
Applies to vehicles with diesel engine: The diesel particulate filter
can filter out almost all soot particles contained in the exhaust gas.
In normal driving conditions the filter is self-cleaning. Should the
self-cleaning function of the filter not be able to operate, e.g. when
the vehicle is continuously used only for short trips, the filter
becomes obstructed with soot and the symbol

for the diesel
particulate filter lights up ⇒page 38.
WARNING
•
Because of the high temperatures which can occur in the emis-
sion control system (catalytic converter or diesel particulate
filter), do not park the vehicle where the exhaust can come into
contact with flammable materials under the car (e.g. on grass or
at the forest edge). - Fire hazard!
•
Do not apply any underseal agents in the area around the
exhaust system - fire hazard!
How to improve economy and minimise pollutionFuel economy, environmental impact and wear on the engine,
brakes and tyres depend largely on the way you drive the vehicle. By
adopting an economical driving style and anticipating the traffic
situation ahead, you can reduce fuel consumption by 10-15%. The
following section gives you some tips on lessening the impact on
the environment and reducing your operating costs at the same
time.
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Your vehicle and the environment 230Anticipate well in advance
A car uses most fuel when accelerating. If you anticipate hazards
and speed changes well in advance, you will need to brake less and
thus accelerate less. Wherever possible, let the car slow down grad-
ually with a gear engaged, for instance when you can see that the
next traffic lights are red. This takes advantage of the engine
braking effect, reducing wear on the brakes and tyres. Emissions
and fuel consumption will drop to zero due to the overrun fuel cut-
off.
Change gear early to save fuel
An effective way of saving fuel is to change up quickly through the
gears. Running the engine at high rpm in the lower gears uses an
unnecessary amount of fuel.
Manual gearbox: Shift up to second gear as soon as possible. If
possible, we recommend shifting up to the next gear at approx.
2,000 rpm.
Automatic gearbox: Press the accelerator slowly and avoid using
the “kick-down” feature.
Avoid driving at high speed
Avoid travelling at top speed. Fuel consumption, exhaust emissions
and noise levels all increase very rapidly at higher speeds. Driving at
moderate speeds will help to save fuel.
Do not let the engine idle for longer than necessary
It is worthwhile switching off the engine when waiting in a traffic
jam, at level crossings or at traffic lights with a long red phase. The
fuel saved after only 30 - 40 seconds is greater than the amount of
fuel needed to restart the engine.
The engine takes a very long time to warm up when it is running at
idling speed. Mechanical wear and pollutant emissions are also
especially high during this initial warm-up phase. It is therefore best
to drive off immediately after starting the engine. Avoid running the
engine at high speed.Regular servicing
Regular servicing can establish a basis for good fuel economy
before you start driving. A well-serviced engine gives you the
benefit of improved fuel efficiency as well as maximum reliability
and an enhanced resale value. A badly tuned engine can consume
up to ten percent more fuel than necessary.
Avoid short trips
The engine and emission control system need to reach their proper
working temperature in order to minimise fuel consumption and
emissions.
A cold engine uses disproportionately more fuel. The engine only
reaches its working temperature after about four kilometres, when
fuel consumption will return to a normal level. This is the reason
why we recommend avoiding short trips wherever possible.
Maintain the correct tyre pressures
Always make sure the tyres are inflated to the correct pressures
⇒page 268 to save fuel. If the tyre pressures are just 0.5 bar too low,
this can increase the fuel consumption by as much as 5 %. Due to
the greater rolling resistance, under-inflation also increases tyre
wear and impairs handling.
Do not use winter tyres all through the year; they will increase fuel
consumption by up to 10 %.
Avoid carrying unnecessary loads
Every kilo of extra weight will increase the fuel consumption, so it is
worth checking the luggage compartment occasionally to make
sure that no unnecessary loads are being transported.
A roof carrier is often left in place for the sake of convenience, even
when it is no longer needed. At a speed of 100-120 km/h your car will
use about 12 % more fuel as a result of the extra wind resistance
caused by the roof carrier - even when it is empty.
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Your vehicle and the environment231
Controls
Safety
Driving tips
General maintenance
Self-help
Technical data Save electrical energy
The engine drives the alternator to generate electricity. This means
that fuel consumption rises when more power is required for elec-
trical equipment. Switch off electrical equipment when it is not
needed. Electrical equipment which uses a lot of electricity includes
the blower (at a high setting), the rear window heating and the seat
heating*.
Environmental compatibilityEnvironmental protection is a top priority in the design, choice of
materials and production of your new Audi.
Design measures for economical recycling•
Joints and connections designed for ease of dismantling
•
Modular construction to facilitate dismantling
•
Increased use of single-grade materials
•
Plastic parts and elastomers are labelled in accordance with ISO
1043, ISO 11469 and ISO 1629
Choice of materials
•
Nearly all materials used can be recycled
•
Similar types of plastics grouped together for easy recycling
•
Recycled materials used in manufacture
•
Reduced vapour emissions from plastics
•
CFC-free refrigerant in air conditioner
Compliance with the laws prohibiting the use of: Cadmium,
asbestos, lead, mercury and chrome VI.
Manufacturing methods
•
Using recycling material for manufacturing plastic parts
•
Solvent-free cavity sealing
•
Solvent-free wax for protecting the vehicles in transit
•
Solvent-free adhesives
•
No CFCs used in production
•
Surplus materials used extensively for energy conversion and
building materials
•
Overall water consumption reduced
•
Heat recovery systems
•
Water-soluble paint
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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
Driving tips
General maintenance
Self-help
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
Controls
Safety
Driving tips
General maintenance
Self-help
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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Towing a trailer237
Controls
Safety
Driving tips
General maintenance
Self-help
Technical data
– 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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