2009 AUDI A4 CABRIOLET brake light

The direction in which the driver wishes to travel is determined with
the aid of the steering angle and vehicle speed and is continua lly
compared with the actual behavior of the vehicle. If the two do not
match, -for example, when the vehicle starts hydrop laning on a
wet road -, ESP will automatical ly brake the appropriate wheel to
correct the problem.
The veh icle is then stabi lized by the forces act ing on the whee l
during braking. If the vehicle is oversteering (rear tends to skid out
of the turn), the brakes are mainly app lied on the whee l that is on
the outside of the curve. In the case of a vehicle that is understeering
(tendency to s lide out of the curve), the brakes are applied at the
rear wheel that is on the inside of the curve . An acoustic signal indi­
cates when ESP brake application cuts in =>
&.
The system operates across the entire speed range in combinat ion
with the ABS system => page 216 . If the Anti -Lock Brake System
(ABS) malfunctions, the ESP wi ll be out of act ion as well.
Activa tion
When you turn on the engine, ESP w ill automatica lly be activated
and will perform a self -test .
The system can be activated o r deactivated by pressing the butto n
=> page 212, fig . 190 . The warning light comes on when the system
is switched off .
Normally, the ESP should a lways be on, however, it may be advanta­
geous to turn off the system in certain specia l cases when some
degree o f wheel spin is desired such as :
• when driving with snow chains
• when driving in deep snow or on a loose surface (to allow the
whee ls to dig in to reach firm ground)
• when trying to "rock" the vehicle free whe n it has become stuck .
The system shou ld be reactivated once you are no longer in such
situations.
Both , the ABS and EDL systems are still functioning even if the ESP
is switched off .
Controls and equip­
ment Safety first Vehicle operation
Int
ellig ent tec hnol ogy
& WARNING
The Ele ctron ic Stab ilization Program is neve rth ele ss s ubje ct to th e
law s of phy sic s. It is p art icularly important to pay at tent ion to thi s
f ac t on wet and slipper y ro ad s. It i s therefore important th at yo u
alway s adapt your driving to the condition of the road and traffic
c onditio ns. Do not allo w the in crea sed safety prov ided by t he Ele c­
tronic Stabilization Program sy stem to lull you into a ccepting
addition al safety ri sk s.
• Plea se note that when ESP i s deactivated , the drive wheel s can
s pin on icy and slippery ro ads a nd the vehi cle can break away -
d anger of skidding ! C
E lectronic differential lock CEDL)
The electronic differential lock monitors the rotational
speed of the drive wheels.
Gener al notes
The electronic differential lock (EDU helps the car to start moving,
accelerate and c limb a gradien t on surfaces providing poor or
a lmost no grip . Without EDL, this would be difficult , if not impos ­
sible.
How the syst em works
The EDL operates automat ical ly . It monito rs the rotationa l speed of
the drive whee ls on an axle with the he lp of the ABS sensors
=> page 216 . If a noticeable difference in rotational speed between
the drive wheels on one axle is de tected (e.g. on slippery grou nd on
one side), the spinning wheel is braked, thereby transferring power
to the other drive wheel or wheels (a ll -whee l drive) . This is done up
to a speed of about 60 mph ( 100 km/h). Noises from the brake
system signal that wheel spin is being control led.
~
Vehicle care Do-it-yourself service Technical data

___ ln_ te_ ll..,,ig ..,_ e_ n_t _t_ e_ c_ h _ n_o _ l_o _,.g= y,_ __________________________________________ _
Driving off
When driving off, always be sure to keep road conditions in mind as
you accelerate. If one drive wheel spins because it is on a surface
with less grip, gradually increase the pressure on the accelerator
pedal until the car starts to move. The wheel less able to transfer
power spins.
Overheating of brakes
To prevent the disc brake of the braked wheel from overheating if
subjected to excessive loads, the EDL cuts out temporarily. The
vehicle remains operational and behaves in the same way as a
vehicle without EDL.
As soon as the brake has cooled down, EDL switches on again auto­ matically.
& WARNING
• When accelerating on slippery surfaces, such as on ice or snow,
always be careful when depressing the accelerator pedal. Even
with the EDL working, the drive wheels can spin and reduce your ability to control your car. -Risk of crash!
• The increased safety afforded by EDL does not mean that you
can take safety risks. Always adapt your driving style to the road
conditions and traffic situation.
[ i] Tips
If a fault occurs in the ABS, the EDL is also not functioning. This is
indicated by the ABS warning light=>
page 20. •
Anti-Slip Regulation System (ASR)
The Anti-Slip Regulation System prevents the driven
wheels from spinning when the car is accelerating.
General notes
The Anti-Slip Regulation System (ASR) is integrated in the electronic
stabilization program (ESP). When the vehicle starts up and acceler­
ates, the wheels are prevented from spinning by adjusting the
engine power to match the amount of grip available from the road
surface.
How the system works
ASR performs automatically, i.e. without the driver's intervention.
With the aid of the ABS sensors=>
page 276, ASR monitors the
speed of the driven wheels. If the wheels start to spin, the engine
power is reduced automatically until the tires find enough grip to
lock onto the road surface. The system is active across the entire
speed range.
Th e ASR works in conjunction with the ABS. If a malfunction should
occur in the ABS, the ASR will also be out of action.
& WARNING
The increased safety afforded by ASR does not mean that you can
take safety risks. Always adapt your driving style to the road
conditions and traffic situation.
[ i] Tips
To ensure that the ASR works properly, all four wheels must be fitted
with identical tires Any differences in rolling radius of the tires can
cause the system to reduce engine power when this is not desired.
S ee also =>
page 279, "New tires and replacing tires and wheels". •

___ ln_ te_ ll..,,ig ..,_ e_ n_t _t_ e_ c_ h _ n_o _ l_o _,.g= y,_ __________________________________________ _
& WARNING (continued)
• Do not "ride the brakes" by resting your foot on the pedal when
you do not intend to brake. This may cause the brakes to overheat, premature wear and increased stopping distance.
• Under certain climatic and operating conditions such as
passing through water, driving in heavy rain or after washing the
vehicle, the effectiveness of the brakes can be reduced. In winter,
ice can accumulate on the brake pads, linings, discs and drums .
Cautiously apply brakes for a test. Brakes will dry and ice coatings
will be cleaned off after a few cautious brake applications .
• Driving for an extended period of time on salt-covered roads
without using your brakes can also affect braking efficiency. Clean
off accumulated salt coating from brake discs and pads with a few
cautious brake applications.
• If you damage the front spoiler, or if you install a different
spoiler, be sure the air flow to the front brakes is not obstructed.
Otherwise the brake system could overheat reducing the effective ­
ness of the entire brake system.
• Failure of one brake circuit will impair the braking capability
resulting in an increased stopping distance. Avoid driving the
vehicle and have it towed to the nearest Audi dealer or qualified
workshop. u
Brake booster
The brake booster adds extra braking power.
The brake booster works with vacuum pressure which is created
only when the engine is running~ &.
& WARNING
• Never let the vehicle roll to a stop with the engine shut off.
• If the brake booster is not working, for example when towing
your vehicle, or because the brake booster has somehow been
& WARNING (continued)
damaged, the brake pedal must be pressed considerably harder to
make up for the lack of booster assistance. •
Functioning of Anti-Lock Brake System (ABS)
ABS prevents the wheels from locking up under braking.
The ABS contributes effectively to vehicle control since it prevents
the wheels from
locking when the brakes are applied. This means
that the vehicle remains steerable and is less likely to skid.
With ABS you do not need to pump the brake. Just hold the brake
pedal down.
However , do not expect that the ABS shortens braking distance
under
all circumstances. When driving on gravel or on newly fallen
snow on top of icy surfaces, braking distance may be even longer,
therefore, under these circumstances, it is especially important that
you drive slowly and with great care.
How the ABS system works
An automatic check is made when a speed of about 4 mph (6 km/h)
is reached. When this happens, a pumping noise can be heard.
If an individual wheel begins to rotate too slowly in relation to
vehicle speed and tends to lock, the ABS automatically reduces brake pressure to prevent that wheel from locking.
This automatic adjustment process will cause a
slight vibration of
the brake pedal and some noises to alert you that vehicle speed
must be adapted to existing road and traffic conditions.
& WARNING
Although the ABS is very effective, always remember that braking
capability is limited by tire traction . Always adjust your driving
speed according to the road and traffic conditions. Do not let the .,_

& WARNING (c ont in u ed)
ext ra sa fe ty a fforded by the ABS tempt you into t ak in g ex tr a risks .
The ABS cannot overco me th e law s of ph ysics.
[ i J Tips
• If ABS is not funct ioning properly, a warning light will come on.
See
=> page 20.
• If a fau lt occurs in the ABS, the EDL is also not funct ion ing . This
is indicated by the ABS warning light.
Brake assistant
T he brake assistant is designed to achieve the optimum
braking effect.
The brake assistant helps to increase the effective braking power
and thus to achieve a shorter stopping distance . If the driver
presses the brake pedal very quick ly, the brake assistant automati ­
cally boosts the braking force to the maximum level, up to the point
where the anti -lock brake function (ABS) intervenes to stop the
wheels from locking. You should then keep the brake pedal pressed until the vehicle has braked to the required speed. The brake assis­
tant switches itself off as soon as you re lease the brake peda l.
The brake assistant will not be operative if there is a malfunction in
the ABS .
& WARNING
Please remembe r that the accident risk always in cre a se s if you
dri ve to o fa st, e spe cially in cor ner s o r on a slipp ery road , or if you
follow th e vehicle ahead of you too clos ely. An increased a ccident
ri sk ca nnot be comp en sa ted even b y the brake assista nt , s o
alwa ys maintain a safe spe ed . •
Controls and equip­ ment Safety first Vehicle operation
Int
ellig ent tec hnol ogy
Servotronic® -advanced power
steering system
The power steering systems uses the power of the
running engine to allow precise steering with little effort.
The advanced Servotronic ® power steering system senses the road
speed and electronically adjusts power assistance to provide
comfortab le and safe steering response exactly matched to the
vehicle speed.
Power steering will not work if the engine is off. As a result, the
steering whee l wil l be hard to turn .
The power steering fluid level is checked during the schedu led
maintenance services.
0 Note
If there is an electronic ma lfunction, servotronic will still function
like a conventional power steer ing system, providing a constant
steering support force that is no longer proportionate to the vehicle
speed. This is most noticeable when tu rning the steering whee l at
low speeds (for examp le when parking), -more effort wil l be
requi red than usual.
• Be aware of the different than usual steering response and
adjust you r steering force accordingly .
• Have the problem checked and set right by an Audi dealer as
soon as possible .
[ i J Tips
• When the engi ne is running, never hold the steering whee l
turned all the way to the right or to the left for longer than 15
seconds. The power steering pu mp will overheat the hydraulic fluid
if you keep holding the steering wheel turned a ll the way. This is
likely to damage the power stee ring system.
~
Vehicle care Do-it-yourself service Technical data

- Lack of proper maintenance as wel l as improper use of the
vehic le wi ll impair the function of the emission control system
and could lead to damage.
'£> For the sake of the environm ent
Even when the Emission Control System is operating properly, the
exhaust gas can have a su lfur -like exhaust gas sme ll under some
operating states. This depends on the sulfur content of the fuel
being used. Using a different brand of fue l may help, or filling the
tank with lead-free super grade gasoline. •
Avoid damaging the vehicle
When you are driving on poor roads, or over curbs, steep ramps,
etc., make certain that low- lying parts such as spoilers and exhaust
system parts do not bottom out and get damaged.
This is especially true for vehicles with low -slung chassis (sports
chassis)* and fully loaded vehicles.
a
Operate your vehicle economically
and minimize pollution
General
Your personal style of driving will determine the economy
of your vehicle, as well as exhaust and noise levels.
Fuel economy, environmental impact, and wear on your engine,
brakes and tires largely depend on three factors:
• your personal driving style
• operating cond itions
• technica l limitat ions
Controls and equip­
ment Safety first Vehicle operation
Driving
and environm ent
If you anticipate what you need to do next and drive economica lly,
you can easily cut your fuel consumpt ion by 10 -15 percent . This
section wil l give you some tips on how you can help the environ­
ment and your pocketbook.
[ i ] Tips
The consumption est imates as published by ENV IRONMENTAL
PROTECTION AGENCY (EPA) and Transport Canada may not corre ­
spond to your actua l consumption on the road, which will vary
depending upon vehicle load and speed, road and weather condi­
tions, trip length, etc. •
Drive smoothly and keep a lookout ahead
Vehicles use the most fuel when they ore accelerating .
-Avoid unnecessary accelerating and brak ing.
Vehicles use the most fue l when they are accelerating . If you antici­
pate what is going to happen next, you wi ll need to brake less and,
thus, acce lerate less. Let the vehicle coast whenever possib le - for
examp le when you see that the next traffic light is red. •
Avoid full throttle
Driving at moderate speeds saves fuel and improves your
mileage.
-Try and keep well below your car's maximum speed.
Acce lerating gently reduces fuel consumption, engine wear, and
does not disturb the environment.
Fue l consumption, exhaust emissions and engine noise increase
disproportionately at high speeds . If you drive at approximately
three quarters of top speed, fuel consumption wil l be reduced by •
Vehicle care Do-it-yourself service Technical data

___ T_ r _a_ il_e _r_ t_ o_ vv_ in__... g,_ __________________________________________________ _
Trailer towing
Driving with a trailer
General information
Your Audi was designed primarily for passenger transpor­
tation.
If you plan to tow a trailer, please remember that the additional load
will affect durability, economy and performance.
Trailer towing not on ly p laces more stress on the vehicle, it a lso calls
for more concentration from the driver.
For this reasons, always fo llow the operating and driving instruc ­
tions provided and use common sense. •
Technical requirements
Trailer hitch
Use a weight -carrying hitch conforming to the gross trailer weight.
The hitch must be suitab le for your veh ic le and tra iler and must be
mounted securely on the vehicle's chass is at a technically sound
l ocation. Use only a trailer hitch with removable bal l mount. A lways
check with the trailer hitch manufacturer to make sure that you are
using the correct hitch .
Do not u se a bumper hit ch .
The hitch must be installed in such a way that it does not interfere
with the impact-absorbing bumper system . No modifications
should be made to the vehicle exhaust and brake systems . From
time to time, check that all hitch mount ing bo lts re main securely
fastened.
When you are not towing a trai ler, remove the trailer hitch ball
mount. This prevents the hitch from causing damage shou ld your
vehic le be struck from behind
=:, & .
Tire pre ssur e
When towing a trailer, inflate the tires of your vehic le to the cold tire
pressure listed under "Full load"on the s ticker on the right door ­
jamb . Inflate trai ler tires to trai ler and tire manufacturers' specifica ­
tions.
Lights
The head ligh t sett ings should be checked with the trai ler attached
before driving off. Have the head lights adjusted as necessary so
that you can see the road ahead but not blind oncoming traffic.
Check to make sure both vehicle and trailer lights are working prop ­
erly .
Engine cooling sy stem
Towing a trailer makes the engine work harder. It is important tha t
the cooling system's performance stands up to the additional
strain. Make sure that the coo ling sys tem has enough fluid .
Trailer brakes
If your traile r is equipped wi th a braking system, check to be sure
that it conforms to all regu lations .
The trailer hydraul ic brake system must not be direct ly connected to
the vehic le's hydraulic brake system .
Safety chains
Be sure trailer safety chains are properly connected from the trai ler
to the hitch on the vehicle. Leave enough slack in the chains to
permit turning corners. When you install safety chains, make sure
they will not drag on the road when you are driving.
The chains shou ld cross under the trailer tongue to prevent it from
dropping in case of separation from the hitch.
~

Trailer lights
Trailer lights must meet all regulations. Be sure to check with your autho rized Audi dealer for correct wiring , switches and relays .
Mirrors
If you are unable to see the traffic behind you using the regular
outside mirrors, then you
must install extended mirrors. It is impor ­
tant that you always have clear vision to the rear .
& WARNING
After removing the trailer hitch, do not store it in your vehicle. In
case of sudden braking, the hitch could fly forward and injure you
or your passengers .
.1
Operating instructions
Maximum trailer weight
A trailer for your vehicle is limited to a typical class 1 or class 2
trailer .
Trailer load distribution
Be sure the load in the trailer is held securely in place to guard
against shifting, be it forward, backward or sideways.
Never allow a passenger to ride in a trailer~&, in "Driving instruc­
tions".
Tire pressure
When towing a trailer, inflate the tires of your vehicle to the cold tire
pressure listed under "Full load" on the sticker on the right door­
jamb. Inflate trailer tires to trailer and tire manufacturers' specifica­
tions.
Controls and equip­ ment Safety first Vehicle operation
Trailer towing
Lights
The
headlight settings should be checked with the trailer attached
before driving off. Adjust as necessary so that you can see the road
ahead but not blind on -coming traffic.
Check proper working of vehicle and trailer lights .
Safety chains
Be sure trailer safety chains are properly connected from the trailer
to the hitch on the vehicle. Leave enough slack in the chains to
permit turning corners. When you install safety chains, make sure
they will not drag on the road when you are driving.
The chains should cross under the trailer tongue to prevent it from
dropping in case of separation from the hitch .•
Driving instructions
Driving with a trailer always requires extra care and
consideration.
To obtain the best possible handling of vehicle and trailer,
please note the following:
Do not tow a loaded trailer when your car itself is not
loaded.
- Be especially careful when passing other vehicles.
Observe speed limits.
Do not drive at the maximum permissible speed.
- Always apply brakes early.
Monitor the temperature gauge.
Vehicle care Do-it-yourself service Technical data

-Tr
aile r t owing ---=--------------
W eig ht dis tri buti on
Towing a loaded trailer with an empty car resu lts in a high ly
unstable distribution of weight . If this cannot be avoided drive at
ve ry low speeds only to avoid the risk of los ing steering control.
A "ba lanced" rig is easier to operate and control. This means that
the tow vehicle should be loaded to the extent possible and permis ­
sib le whi le keeping the trailer as light as possib le under the circum ­
stances. Whenever possible, transfer some cargo to the luggage
compartment of the tow vehicle while observing tongue load
requirements and vehicle loading considerations .
Speed
The higher the speed, the more difficult it becomes for the driver to
contro l the rig . Do not drive at the maximum permissible speed.
Reduce your speed even more under unfavorable load, weather or
wind condi tions -particularly when going downhill.
Reduce vehicle speed
imm ed iately if the trailer shows the slightest
sign of swaying.
Do not try to stop the s waying by a ccelerating .
Observe speed limits. In some areas speeds for vehic les towing
trai lers are lower than for regular vehicles.
Always app ly brakes early. When driving downhill, shift into lower
gear to use the engine braking effect to slow down the vehicle. Use
of the brakes alone can cause them to overheat and fail.
C oo lan t tem pe ra ture
The coolant temperature gauge~ page 73 must be observed care ­
fully. If the needle moves close to the upper end of the scale, reduce
speed immediately and/or switch off the air conditioner.
If the coolant temperature warning light in the instrument cluster
starts flashing -~- , pul l off the road, stop and let the engine
idle for
about two minutes to prevent heat build -up .
& WARNING
An yone not prop erl y r estr ained in a mo ving ve hic le is at a much
gre ater ri sk in an accident. N ever let an yone rid e in your car who
is not p roperl y wearing the r estraint s pro vid ed by Audi.
c
Trailer towing tips
Important to know
Your vehicle handles differently when towing a trai ler because of
the additional weight and weight distribution . Safety, performance
and economy will great ly depend on how carefu lly you load your
trai ler and operate your rig.
Before you actually tow your trailer, practice turn ing, stopping and
backing up in an area away from traffic. Keep practicing unti l you
have comp letely become familiar with the way your vehicle -trailer
combination behaves and responds .
Backing up is difficu lt and requires practice. Backing up with a
trailer genera lly requires s teering action opposite of that when
backing up your vehic le without a trailer.
Maintain a greater distance between you r vehicle and the one in
front of you. You will need more room to stop.
To compensate for the trailer, you wi ll need a larger than normal
turning radius .
When passing, remember that you cannot accelerate as fast as you nor mally wou ld because of the added load . Make sure yo u have
enough room to pass. After passing, allow plenty of room for your
trai ler before changing lanes again .
Avo id jerky starts, sharp turns o r rapid lane changes.