Intelligent technology199
Controls
Safety
Driving tips
General maintenance
Self-help
Technical data
Note
To ensure that the ASR works properly, all four wheels must be fitted
with identical tyres. Any differences in the rolling radius of the tyres
can cause the system to reduce engine power when this is not
desired. Also refer to ⇒page 245, “Replacing wheels and tyres”.Electronic differential lock (EDL)
The electronic differential lock monitors the speed of the
driven wheels.General notes
The electronic differential lock (EDL) helps the car to start moving,
accelerate and climb a gradient in slippery conditions where this
may otherwise be difficult or even impossible.
How the system works
The EDL acts automatically. With the aid of the ABS sensors
⇒page 197 , the system monitors the rotational speed of the driven
wheels on each axle. Whenever it detects a significant difference in
the speed of the driven wheels of one axle (for example, if the road is
slippery on one side ) the system applies the brake to slow down the
spinning wheel so that more of the power is directed to the other
wheel of this axle (or to the three other wheels on vehicles with four-
wheel drive). This function is active up to about 100 km/h. The brake
system will make noises while it is working.
Driving away from a standstill
Sometimes one wheel has less grip and starts spinning, for
example, if one of the driven wheels is on ice. In this case, keep
pressing the accelerator gradually until the car starts moving, even
though the wheel with less grip will still spin.
Overheating of the brakes
To prevent the disc brake of the braked wheel from overheating, the
EDL cuts out automatically if subjected to excessive loads. The car remains operational and will behave in the same way as a car
without EDL.
The EDL will switch on again automatically when the brake has
cooled down.
WARNING
•
When accelerating on a uniforml
y slippery surface (for instance
all four wheels on ice or snow), press the accelerator gradually and
carefully. The driven wheels may ot herwise start to spin (in spite
of the EDL), which would impair th e car's stability and could lead
to an accident.
•
Even with EDL, you should always adjust your speed to suit the
conditions. Do not let the extr a safety provided tempt you into
taking any risks when drivin g – this can cause accidents.Note
If the ABS warning lamp lights up, th is can also mean there is a fault
in the EDL. Please contact a qualified workshop as soon as
possible.BrakesNew brake pads
New brake pads do not give full br aking effect for the first 400 km,
they must first be “bedded in”. However, you can compensate for
the slightly reduced braking effect by applying more pressure on
the brake pedal. Avoid placing a heavy load on the brakes during the
running-in period.
We ar
The rate of wear on the brake pads depends a great deal on how you
drive and the conditions in which the vehicle is operated. Negative
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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 ful l-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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Intelligent technology203
Controls
Safety
Driving tips
General maintenance
Self-help
Technical data
Dynamic power management
While the vehicle is moving, this function distributes the available
power to the various electrical components and systems according
to their requirements. The power management ensures that on-
board systems do not consume more electrical power than the
alternator can supply, and thus
maintains the maximum possible
battery power level.
Note
•
The power management system is not able to overcome the
given physical limits. Please reme mber that the power and life of
the battery are limited.
•
A warning message will appear ⇒page 204, “Driver message in
the instrument cluster display” if the battery power has dropped to
a level where reliable starting is impaired.
Points to remember
Starting ability has first priority.Short trips, city traffic and low te mperatures all place a heavy load
on the battery. In these conditions a large amount of power is
consumed, but only a small amount is supplied. The situation is also
critical if electrical equipment is in use when the engine is not
running. In this case power is consumed when none is being gener-
ated.
In these situations you will be aware that the power management
system is intervening to control the distribution of electrical power.
When the vehicle is parked 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. 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 yo
u unlock the vehicle. These func-
tions will be restored when you switch on the ignition and start the
engine.
With the engine switched off
If you listen to the radio or us e the other MMI functions when the
engine is not running, this will discharge the battery.
The MMI display will show this wa rning 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 am ount 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 alternat or to meet the greater power
requirement and charge the battery at the same time.
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Towing a trailer
210•
In low outside temperatures , both the towing vehicle and the
trailer should be fitted with winter tyres.
WARNING
It is essential that you adjust your speed to suit the weather, road
and traffic conditions. Do not let the trailer stabilisation system
tempt you into taking any risks wh en driving – this can cause acci-
dents.•
The ESP and trailer stabilisatio n system cannot defy the laws
of physics. This should be kept in mind, particularly on slippery
and wet roads and when towing a trailer with a light load.
•
The trailer stabilisation system is functional, regardless of
whether the trailer has a mechanical overrun brake or not.
•
The trailer stabilisation system is not always able to detect
swaying of trailers with a light load and will therefore not inter-
vene.
•
A trailer can still “jack-knife” on slippery roads with little grip,
even if the towing vehicle is eq uipped with the trailer stabilisation
system.
•
Trailers with a high centre of gravity may even tip over before
they start to sway sideways.
•
If you are not towing a trailer, but the trailer socket is being
used (e.g. for an illuminated bicycl e rack), the trailer stabilisation
system may be activated in extreme driving conditions.
•
Please note the additional information and warnings
⇒ page 210 .
Notes on towing
Driving with a trailer always requires extra care.Weight distribution
Try to avoid towing a loaded trailer with an unladen vehicle. If this
cannot be avoided, drive extra slowly to allow for the unbalanced
weight distribution.
Speed
The stability of the car and trailer is reduced with increasing speed.
For this reason it is advisable not to drive at the maximum permis-
sible top speed in unfavourable road, weather or wind conditions.
This applies especially on a downhill gradient.
You should always reduce speed immediately if the trailer shows
the slightest sign of swaying. Never try to stop the swaying by accel-
erating further.
Always brake in good time. If the trailer has an overrun brake, apply
the brakes gently at first and then firmly. This will prevent the jerking
that can be caused by the trailer wheels locking. Change down in
good time before going down a steep hill so that you can use the
engine braking effect to slow down the vehicle.
Swaying and pitching can be reduced by stabiliser aids. We recom-
mend having stabiliser aids installed when towing trailers with a
high trailer weight. They can be purchased and installed at an Audi
dealer.
Overheating
When climbing long hills in hot weather with the engine running
fast in low gear, you should keep an eye on the coolant temperature
gauge ⇒page 11 . Reduce speed immediately if the needle moves to
the top end of the scale. If the temperature warning lamp
in the
instrument cluster should start flashing, stop the car and let the
engine cool down by running it at idling speed for a few minutes.
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Towing a trailer211
Controls
Safety
Driving tips
General maintenance
Self-help
Technical data
Accessories
Before mounting equipment an d 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 dama
ge to the towing bracket. In an
extreme case, damage to the towing bracket could cause it to break
⇒ .
WARNING
•
If you wish to mount equipmen t 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 coul d damage the mechanism wh ich locks the ball joint
in place and impair it s safety (accident risk).
Removable towing bracketApplies to vehicles: with removable towing bracketIntroduction
Special care is required when fitting and removing the
towing bracket.
Fig. 205 Load distribu-
tion of equipment and
accessories
A1A1
AAAB
Fig. 206 Luggage
compartment with
towing bracket
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Towing a trailer
212The removable ball joint attachment for the towing bracket is stored
under the floor panel on the left-h and side of the luggage compart-
ment.
The ball joint can be fitted and removed by hand.
WARNING
Never use tools of any kind when fitting and removing the ball
joint. This coul d damage the mechanism wh ich locks the ball joint
in place and impair it s safety (accident risk).
Note
•
Do not attempt to modify or repair the ball joint or other towing
bracket components.
•
Should you have any difficulties when using the towing bracket,
or suspect that it is not fitted properly, contact a qualified workshop.
•
Before setting off, always check that the ball joint is secured
properly ⇒page 214 .
•
Never disengage the ball joint with the caravan / trailer still
hitched or with a bicycle rack or similar accessory still attached.
•
It is advisable to remove the ball joint when you are not towing a
trailer. Fold the socket back to its original position so that the
mounting fixture is properly closed.
•
The ball joint must be removed if you intend to clean the car with
a steam cleaning attachment. Make sure that the mounting fixture
is properly closed.
•
For installation and removal of the ball joint we recommend that
the gloves provided be used.
Applies to vehicles: with removable towing bracketFitting the ball joint (step 1)– Remove the bumper cover to access the socket unit.
– Fold the socket unit all the way out in the direction of the arrow ⇒fig. 207.
– The cover piece is held automatically in the open posi- tion.
– Check that the mounting for the towing bracket, which will now have become visible -arrow- ⇒fig. 208, is free of
dirt, and clean if necessary ⇒.
Fig. 207 Area below
rear bumper: Folding
down the socketFig. 208 Socket
(folded down)
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Towing a trailer213
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 213, “Fitting the ball joint (step 2)”.
WARNING
It is important to keep the mounti ng 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. 209 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 213, “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. 210 for locking the ball joint into
the lock on the knob and turn it clockwise.
Fig. 209 Removable
towing bracket: Ball
joint
A2A1A3
Fig. 210 Removable
towing bracket:
Setting the spring
mechanism to the
"ready" positionFig. 211 Removable
towing bracket:
Inserting the ball joint
A4
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Towing a trailer
214
– Pull out the knob in direction , hold and turn in direc-tion until the locking ball engages ⇒.
Inserting the ball joint
– With the spring mechanism in the “ready” position, insert the ball joint into the mounting fixture and push it
upwards ⇒page 213, fig. 211 in the direction indicated
(arrow) ⇒. The spring mechanism should then
engage automatically wi th an audible click.
– Lock the ball joint by turn ing the key anti-clockwise.
– Take out the key and press the cover cap provided onto the lock.Continued ⇒page 214, “Fitting the ball joint (step 4)”.
WARNING
•
If it is not possible to set th e spring mechanism to the "ready"
position as described abov e, do not use the ball joint. Please take
your vehicle to a qualified workshop.
•
To avoid injury, keep your hand s away from the knob and the
cover piece when inserting the ball joint into the mounting fixture.Note
Make sure that the knob can turn freely when the ball joint is
inserted.
Applies to vehicles: with removable towing bracketFitting the ball joint (step 4)Safety check
– Check that the green marking ⇒fig. 212 on the knob
is inside the green zone on the ball joint.
– Check that the knob is directly against the ball joint, so that there is no gap between the knob and the ball
joint.
– Check that the ball joint is locked and the key is removed (so that the knob cannot be pulled out).
Aa
Ab
A5
Fig. 212 Removable
towing bracket: Safety
checkFig. 213 Area below
rear bumper: Electrical
socket for trailer
A6
A7
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