service AUDI A5 2008 8T / 1.G User Guide

Airbag system177
Controls
Safety
Driving tips
General maintenance
Self-help
Technical data
•
The airbag system can only be activated once; if the airbag has
been triggered, the system must be replaced. Should the airbag
system or airbag modules have to be replaced, the qualified work-
shop carrying out the replacement will document all details in the
appropriate section of the Service Schedule.
•
If you sell the vehicle, please remember to pass on the
complete Service Wallet to the new owner. If any of the airbags
have been deactivated, it is important that the new owner is also
given the relevant documents.
•
The relevant safety requirements must be observed when the
vehicle or components of the airbag or belt tensioner systems are
scrapped.
•
In an accident in which one or more airbags are triggered the
alternator and the starter are - for safety reasons - both discon-
nected from the battery via a pyrotechnic circuit breaker.
−Any repairs to the pyrotechnic circuit breaker must always
be performed by a qualified workshop (accident risk).
−The relevant safety requirements must be observed when
the vehicle or the circuit breaker are scrapped.
When are the airbags triggered?
The airbag system is triggered in collisions with a severe
impact.The airbag system is designed so that the airbags for the driver and
front passenger are triggered in a severe frontal collision.
In severe side collisions the side airbags on the impact side of the
vehicle are triggered together with the head-protection airbag.
The front airbags, side airbags and one of the head-protection
airbags may be triggered together in certain types of accident.The airbag system is not triggered in minor frontal or side collisions,
or in rear collisions or if the car overturns. In these situations the
occupants are protected by wearing the seat belts.
Factors determining the triggering response
It is not possible to define the exact triggering response of the
airbag system in all possible situations, since the circumstances in
different types of accident will vary considerably. Important factors
include, for example, the nature (hard or soft) of the object which
the car hits, the angle of impact, vehicle speed and so on.
Whether the airbags are triggered depends primarily on the vehicle
deceleration rate resulting from the collision. By processing the
signals from the sensors located in the vehicle, the electronic
control unit is immediately able to evaluate the severity of the colli-
sion and activate the restraint systems accordingly. If the decelera-
tion rate is below the predefined reference value in the control unit
the airbags will not be triggered, even though the accident may
cause extensive damage to the car.
Note
The airbag releases a fine dust when it inflates. This is quite normal
and does not mean there is a fire in the vehicle.
WARNING (continued)
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Intelligent technology201
Controls
Safety
Driving tips
General maintenance
Self-help
Technical data
Power steering (servotronic)The power steering assists the driver when turning the
steering wheel (with the engine running).The power steering assists the driver by reducing the force needed
to turn the steering wheel. The degree of power assistance is
adapted electronically, depending on the speed.
If a fault should occur in the servotronic system the power steering
will still operate. The degree of power assistance will, however, no
longer adapt to different speeds. If the electronic regulating system
is not working properly, this is most noticeable when turning the
steering wheel at low speeds (for instance when parking) – more
effort will be required than usual. The fault should be corrected by
a qualified workshop as soon as possible.
The power steering does not function when the engine is switched
off. In this case the steering wheel is very hard to turn.
If the steering is held at its turning limit when the car is stationary,
this will place an excessive load on the power steering system. In
this case, the power steering system will make noises. It will also
reduce the idling speed of the engine.
Caution
Do not keep the steering in the full-lock position for longer than
15 seconds when the engine is running – this could cause damage
to the power steering system.
Note
•
If the power steering should fail at any time or the engine is
switched off (for instance when being towed), the car can still be
steered. However, more effort will be required to turn the steering
wheel.
•
If the system is leaking or malfunctioning, please take the car to
a qualified workshop as soon as possible.
•
The power steering requires a special hydraulic fluid. The fluid
reservoir is located at the front of the engine compartment on the
left ⇒page 232. The correct fluid level in the reservoir is important
for the power steering to function properly. The hydraulic fluid level
is checked at the Inspection Service.
Applies to vehicles: with four-wheel driveFour-wheel drive (quattro
®)
On quattro models the engine power is distributed to all
four wheelsGeneral notes
On four-wheel drive vehicles, the engine power is distributed to all
four wheels. The distribution of power is controlled automatically
according to your driving style and the road conditions. Also refer
to ⇒page 199, “Electronic differential lock (EDL)”.
The four-wheel drive is specially designed to complement the supe-
rior engine power of your Audi. This combination gives the car
exceptional handling and performance capabilities – both on
normal roads and in more difficult conditions, such as snow and ice.
Even so (or perhaps especially for this reason), it is important to
observe certain safety points ⇒.
Winter tyres
Thanks to its four-wheel drive, your car will have plenty of traction
in winter conditions, even with the standard tyres. Nevertheless, we
still recommend that winter tyres or all-season tyres should be fitted
on all four wheels when winter road conditions are expected, mainly
because this will give a better braking response.
Snow chains
On roads where snow chains are mandatory, this also applies to cars
with four-wheel drive ⇒page 248, “Snow chains”.
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Your vehicle and the environment 206safety reasons, the dip settings may only be changed by a qualified
workshop.
For further information, please consult an Audi dealer or other qual-
ified workshop.
Unleaded petrol
A car with catalytic converter must not be run with leaded petrol
⇒page 205. Before driving abroad make sure that unleaded petrol
is available there.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.
Anticipate 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
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Towing a trailer209
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 56.
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.
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.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 196,
•
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 36, “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.
•
The trailer overrun brake must be set correctly. This is important
to ensure that the trailer can be braked correctly, to avoid the vehicle
and trailer “jack-knifing” and to prevent excess braking of the trailer.
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Fuel and filling the tank227
Controls
Safety
Driving tips
General maintenance
Self-help
Technical data
Fuel and filling the tankPetrolApplies to vehicles: with petrol enginePetrol grade
The correct grade of petrol is listed inside the fuel tank
flap.The vehicle is equipped with a catalytic converter and must only be
run on unleaded petrol. Unleaded petrol must comply with the
European EN 228 standard. The petrol grades have different octane
ratings (RON). If, in exceptional circumstances, the correct octane
rating is not available, please note the following:•
For engines which require Premium unleaded petrol (95 RON)
according to ⇒page 295, “Performance, weights and dimensions”:
Regular unleaded fuel with 91 RON can also be used. This will,
however, result in a slight loss of power.
•
For engines which require Super Plus unleaded petrol (98 RON)
according to ⇒page 295, “Performance, weights and dimensions”:
Premium unleaded fuel with 95 RON can also be used. This can,
however, result in a slight loss of power under certain driving condi-
tions. – If premium unleaded petrol is not available, the engine can
be run on regular unleaded petrol with 91 RON as an emergency
measure. In this case only use moderate engine speeds and a light
throttle. Avoid using full throttle. Fill up with premium or Super Plus
petrol as soon as possible.Caution
•
Petrol complying with the EN 228 standard can contain small
quantities of ethanol. However, “bioethanol fuels”, which are
retailed under various different names such as E50 and E85, and
which contain a large proportion of ethanol, must not be put into
the vehicle, as this would damage the fuel system.
•
Even one tankful of leaded fuel would permanently impair the
efficiency of the catalytic converter.
•
High engine speed and full throttle can damage the engine when
using petrol with an octane rating lower than the correct grade for
the engine.
DieselApplies to vehicles: with diesel engineDiesel fuel
Please note the information on the inside of the fuel tank
flap.Diesel fuel must comply with the European EN 590 standard. It must
have a cetane number (CN) of at least 51. The cetane number indi-
cates the ignition quality of the diesel fuel.
Winter-grade diesel
Diesel fuel can thicken in winter. For this reason petrol stations in
some countries also offer winter diesel.
Caution
•
The vehicle is not designed for the use of biodiesel (FAME fuel).
The fuel system would be damaged if you use biodiesel.
•
Do not mix fuel additives (“thinners”, petrol or similar additives)
with the diesel fuel.
•
If poor-quality diesel fuel is used, it may be necessary to drain
the water separator on the fuel filter more frequently than is speci-
fied in the Service Schedule. We recommend having this done by a
specialist workshop. If water is allowed to collect in the filter, this
can cause engine performance problems.
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Checking and topping up fluids233
Controls
Safety
Driving tips
General maintenance
Self-help
Technical data The positions of the engine oil filler cap and the engine oil dipstick
⇒page 232, fig. 223 (items and ) may be different on some
engine versions.
Engine oilGeneral notesWe recommend that you have the oil change carried out by an Audi
dealership/qualified workshop according to the intervals stated in
the Service Schedule or according to the service interval display in
the instrument cluster.
Whether your vehicle is serviced at flexible service intervals or fixed
service intervals is shown in the Service Schedule.
The correct oil specifications for your engine are listed in the Te c h -
nical data section ⇒page 295, “Performance, weights and dimen-
sions”.
Check that the specifications quoted (VW standards) appear on the
container either singly or in combination with other specifications.
Flexible service intervals (Audi LongLife Service*)
Special engine oils ⇒page 295, “Performance, weights and dimen-
sions” have been developed as part of the Audi LongLife Service
(⇒“Service Schedule”).
This type of oil must be used if you intend to take advantage of the
extended maintenance intervals allowed by the Audi LongLife
Service.•
Do not mix the LongLife oil with oil intended for fixed service
intervals, as the requirements for the extended service intervals are
then no longer guaranteed.
•
In exceptional circumstances, if the engine oil level is too low
⇒page 234 and you cannot obtain the specified LongLife oil, you
can put in a small quantity of oil for fixed service intervals -
⇒page 295, “Performance, weights and dimensions”. This should not be done more than once and no more than 0.5 litres should be
used.
Fixed service intervals (Inspection Service)*
If you do not take advantage of the LongLife service for your car, you
can use the oils for fixed service intervals - ⇒page 295, “Perform-
ance, weights and dimensions”. In this case, your car must be serv-
iced after a fixed interval of 1 year / 15,000 km (10,000 miles) – see
Service Schedule.
•
In exceptional circumstances, if the engine oil level is too low
⇒page 234 and you cannot obtain the oil specified for your vehicle,
you can put in a small quantity of oil conforming to the specification
ACEA A2 or ACEA A3 (petrol engines) or ACEA B3 or ACEA B4 (diesel
engines). This should not be done more than once and no more than
0.5 litres should be used.
Vehicles with diesel particulate filter*
The Service Schedule states whether your vehicle is fitted with a
diesel particulate filter.
•
Vehicles with diesel particulate filter must only be filled with
engine oil VW 507 00. This oil can be used regardless of whether the
vehicle is serviced at flexible service intervals (Audi LongLife
Service) or fixed service intervals.
•
Avoid mixing this oil with other engine oils.
•
In exceptional circumstances, if the engine oil level is too low
⇒page 234 and you cannot obtain the oil specified for your vehicle,
you can put in a small quantity of oil conforming to the specification
VW 506 00 / VW 506 01 or VW 505 00 / VW 505 01 or ACEA B3 /
ACEA B4. This should not be done more than once and no more than
0.5 litres should be used.
A3
A4
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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 tyres243
Controls
Safety
Driving tips
General maintenance
Self-help
Technical data
Wheels 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
kerb.
– Inspect the tyres regularly for damage (cuts, cracks or
blisters, etc.). Remove any foreign bodies embedded in
the treads.
– Damaged wheels and tyres must be replaced immedi-
ately.
– 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
longer.
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
inspected.
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. 231 Open driver's
door (LHD vehicle) with
sticker listing tyre
inflation pressures
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Self-help255
Controls
Safety
Driving tips
General maintenance
Self-help
Technical data
Applies to vehicles: with fire extinguisherFire extinguisherThe factory-fitted fire extinguisher is located in the foot-
well on the front passenger's side (secured in a holder).Taking out the fire extinguisher
– Unfasten the retaining strap by pressing on the tab
marked “PRESS” ⇒fig. 236 -arrow-.
– Take the fire extinguisher out of the holder.
Securing the fire extinguisher
– Place the fire extinguisher in the holder.
– Secure the fire extinguisher with the retaining strap.
After using the fire extinguisher
– Have the fire extinguisher refilled and checked by a qual-
ified dealer or the fire service.Check how the fire extinguisher works before you need to use it. The
instructions for use are shown on the fire extinguisher.Have the fire extinguisher checked regularly (at least every two
years) by a qualified dealer or by the fire service to ensure that it will
be in working order when you need it.
When buying a new fire extinguisher, make sure it fits in the holder.
WARNING
If the fire extinguisher is not secured properly it could be cata-
pulted through the vehicle during driving and braking manoeuvres
or in the event of an accident. This poses a risk of injury to occu-
pants.
Note
•
The fire extinguisher must comply with legal requirements.
•
Observe the expiry date of the fire extinguisher. The fire extin-
guisher may not work properly after the expiry date.
Tools and Tyre Mobility SystemThe tools and the Tyre Mobility System are stored under
the floor panel in the luggage compartment.
Fig. 236 Fire extin-
guisher in footwell on
front passenger's side
Fig. 237 Luggage
compartment: Tools,
Tyre Mobility System
and jack
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