2009 AUDI A4 CABRIOLET Brake

• .___H_ o_m _ e_ L_ i_ n _k_ ®_R __________________________________________________ _
App lies to vehicles: w ith Homelin k® un ive rsal remote contro l
Programmi ng th e Hom eLink ® transmitt er
The transmitter is programmed in two phases. For rolling
code transmitters, a third phase is also necessary .
Fig. 151 Overhead
console : Homelink®
keypad
Fig.152 Frontbumper,
driver side: location of
transmitter unit
Phase 1: programming the overhead keypad
1. Make sure your vehicle is w ithin operat ing range o f the
remote controlled garage door opener .
2. Set the parking brake=>
& in "General information" on
page 139.
3. Turn the ignit ion on. Do not sta rt the engine! 4. Press and ho
ld the two outside Homelink® buttons
(D
and @for app roximately 20 seconds until indicator
light ©=:> fig.
151 beg ins to flash. Then release both
buttons . Do not hold the buttons for longer than
30
seconds.
This procedure only needs to be performed
once. It
erases the factory-set default codes and does not have to
be repeated to program additional remote controls.
5. Press and hold the Homelink ® button (D, ® or @ until
the indicator light © starts flashing
slowly. Release the
button.
- The system will remain in programming mode for 5
minutes.
Go to the front of the v ehicle and proceed w ith
phase 2.
Phase 2:
programming the bumper mounted transmitter
6. Hold the original remote control at a distance between 0-
6 in. (0-15 cm) from the b umper below the appropriate
headlight for your vehicle => fig.
152 (use the shortest
distance possible) .
7. Aim the remote control just below the
driver side head­
lig ht.
8. Press and hold the act ivation button on the remote
control.
- May be different in Canada . If so, press and re-press
(cycle) the activation button on your remote control every
two seconds. -.,

________________________________________________ D_r_iv _ i _n_, g,::._ S_ a_ fe__, ly'-------.J"'
Only use floor mats that leave the pedal area free and can be
secured with floor mat fasteners.
If a brake circuit fails, increased brake pedal travel is required to
bring the vehicle to a full stop.
& WARNING
Pedals that cannot move freely can cause loss of vehicle control
and increase the risk of serious injury.
• Never place any objects in the driver's footwell. An object could
get into the pedal area and interfere with pedal function . In case
of sudden braking or an accident, you would not be able to brake
or accelerate!
• Always make sure that nothing can fall or move into the
driver's footwell. •
Floor mats on the driver side
Always use floor mats that can be securely attached to
the floor mat fasteners and do not interfere with the free
movement of the pedals.
-Make sure that the floor mats are properly secured and
cannot move and interfere with the pedals~&.
Use only floor mats that leave the pedal area unobstructed and that
are firmly secured so that they cannot slip out of position. You can
obtain suitable floor mats from your authorized Audi Dealer.
Floor mat fasteners are installed in your Audi.
Floor mats used in your vehicle must be attached to these fasteners.
Properly securing the floor mats will prevent them from sliding into
positions that could interfere with the pedals or impair safe opera ­
tion of your vehicle in other ways .
Controls and equip­
ment Safety first Vehicle operation
& WARNING
Pedals that cannot move freely can result in a loss of vehicle
control and increase the risk of serious personal injury.
•
Always make sure that floor mats are properly secured .
• Never place or install floor mats or other floor coverings in the
vehicle that cannot be properly secured in place to prevent them
from slipping and interfering with the pedals or the ability to control the vehicle.
• Never place or install floor mats or other floor coverings on top
of already installed floor mats. Additional floor mats and other
coverings will reduce the size of the pedal area and interfere with
the pedals.
• Always properly reinstall and secure floor mats that have been
taken out for cleaning .
• Always make sure that objects cannot fall into the driver foot­
well while the vehicle is moving. Objects can become trapped
under the brake pedal and accelerator pedal causing a loss of
vehicle control . •
Stowing luggage
Loading the luggage compartment
All luggage and other objects must be properly stowed
and secured in the luggage compartment.
Loose items in the luggage compartment can shift
suddenly, changing vehicle handling characteristics. Loose
items can also increase the risk of serious personal injury in
a sudden vehicle maneuver or in a collision.
- Distribute the load evenly in the luggage compartment . ..,
Vehicle care Do-it-yourself service Technical data

-In
te llig ent tec hnolo gy --=---=-=-------------
Intelligent technology
Notice about data recorded by
vehicle control modules
Your vehicle is not equipped with an Event Data Recorder (EDRl,
installed by some manufacturers for the express purpose of
capturing data for retrieval after an accident or crash event . EDR's
are sometimes called "crash recorders" .
Some state laws restrict the retrieva l or downloading of data stored
by EDR's that were insta lled in a vehicle for the express purpose of
retrieving data after an accident or crash event without the owner's
consent.
Although your vehicle is not equipped with an EDR, it is equipped
with a number of electronic control modules for various vehicle systems such as, for examp le, engine function, emission control, as
we ll as for the airbags and safety belts.
T hese electronic control modules also record vehic le-rela ted da ta
during norma l ve hicle operation for diagnost ic and repair purposes .
The recording capacity of the electronic control modules is limited
to data (no sound is recorded) and only a small amount of data is
actually recorded over a very limited period of time and stored when
a system fault or other condition is sensed by a control unit. Some
of the data then stored may relate to vehic le speed, d irection,
braking as we ll as restraint system use and performance in the
event of a crash or other condition . Stored data can only be read and
down loaded with special equipment. •
Electronic Stabilization Program (ESP)
General information
The ESP improves the vehicle s tability.
I
A F ig . 19 0 Cen ter
co nsol e w ith ESP
sw itch
ESP is designed to he lp you maintain vehic le control in situa tions
where the car approaches the limits of "grip", especially when acce lerating and cornering . ESP reduces the risk of skidding and
improves stability under all road conditions .
The syst em opera tes across the en tire speed range in combination
with the ABS system. If the Anti-Lock Brake System (ABS) malfunc ­
tions, the ESP wil l a lso shut down .
How th e sys te m work s
The Anti-Lock Brake System (ABS) , E lectronic Differential Lock (EDU
and the Anti -Sl ip Regu lation System (ASR) are integrated in the e lec­
tronic stabi li z ation program. In addition to the data provided by
these functions, the ESP control unit requires additional measure­ ment data provided by high performance sensors . T he rotational
speed of the vehic le about its ver tica l axis, t he late ral acce leration
acting on the vehic le, the brake pressure and the steering ang le are
a ll measured .

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.
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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". •

Braking
General information
What affects braking efficiency?
O pera tin g co ndition s and drivi ng h abit s
The brakes on today's automobiles are still subject to wear,
depending large ly on operating conditions and dr iving habits~
&­
On vehicles that are either driven mostly in stop -and -go city traffic
or are driven hard, the brake pads shou ld be checked by your autho­
rized Audi dealer more often than specified in the
W arr anty & Main ­
t e nanc e bo okle t.
Fai lure to have you r brake pads inspec ted ca n
resu lt in reduced brake performance.
On steep slopes, you shou ld use the braking effect of the engine.
This way, you prevent unnecessary wear on the brake system. If you must use your brakes, do not hold the brakes down continuous ly.
Pump the brakes at intervals.
Moi sture or road salt
If you are driv ing faster than 50 mph (80 km/h) and the windshie ld
wipers are on, the brake pads wi ll briefly touch the brake discs in
regu lar intervals so as to improve reaction time when braking on
wet surfaces. You, the driver, wil l not notice anything.
Under ce rta in conditions, for example, when dr iving through water
or very heavy rain, or even after washing your vehicle, the braking
effect can be reduced due to moisture (or in freezing conditions ice)
on the brake pads. A few cautious brake applications should dry off
the b rake pads or remove any ice coatings .
At speeds
over80 km/h and with the windshie ld wiper turned on, the
brake pads are app lied briefly to the brake discs. This occurs at
regu lar interva ls wi thout the driver not icing and provides for better
brake response time under wet conditions.
The effectiveness of the brakes can be reduced when the vehicle is driven on a sa lt-covered road and the brakes are not used. Likewise,
Controls and equip­
ment Safety first Vehicle operation
Int
ellig ent tec hnol ogy
you clean off accumulated sa lt coating from brake discs and pads
with a few ca utious applications of the brake ~
&-
Cor rosi on
There may be a tendency for dirt to build up on the brake pads and
corrosion to form on the discs if the car is not driven regularly or
only f or sho rt trips with little use of the brakes.
If the brakes are not used frequently, or if corrosion has formed on
the discs, it is advisable to clean off the pads and discs by braking
firm ly a few times from a moderately high speed~
&-
Fa ults in the brake system
If you shou ld notice a sudden increase in brake pedal trave l, then
one of the two brake circuits may have failed~
&-
Lo w brak e fluid l evel
Malfunctions can occur in the brake system i f the brake fluid level is
too low . The brake fluid level is monitored electronically .
Brake lining wear statu s
Brake lining wear may be checked by visua l inspection of the condi ­
tion o f the brake pads through the open ings in the wheel. If neces­
sary, the wheel may be removed for this inspection
~ page 293,
"Whee l change".
& WARNING
• You should perform braking maneuver s for the purpo se of
cl eani ng th e br ake sy stem onl y if ro ad condition s permit . Other
road u se rs mu st not be put a t ris k -you may cau se an accident!
• Before des cending a steep gr ade , reduce sp eed and sh ift tr ans ­
mi ssion into a lower gear or lower driving po sition . Do not ride the
brake s or hold the pedal d ow n too long or t oo often . This could
cau se the brake s to get hot and dimini sh brakin g efficien cy . _.
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,_ __________________________________________ _
& 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.
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Vehicle care Do-it-yourself service Technical data