2009 AUDI Q7 brakes

•
The direction in which the driver wishes to travel is determined with
t he 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 vehic le starts hydrop laning on a wet
road, ESP will automatically brake the appropriate whee l to correct
the prob lem.
The vehicle is then stab ilized by the forces acting 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 wheel that is on
the outside of the curve. In the case of a vehicle that is
understeering
(tendency to sl ide out of the curve), the brakes are applied as
needed on the wheel that is on the inside of the curve or additionally
on the other wheels . An acoustic signal indicates when ESP brake
application cuts in
~ & .
The system operates across the entire speed range in combination
with the ABS system
~ page 292 . If the Anti-Lock Brake System
(ABS) malfunctions, the ESP will b e out of action as well.
Ac tiva tin g
When you turn on the engine, ESP will automatically be activated
and wil l perform a se lf-tes t. As soon as the test is comp leted, the
system is in norma l operating mode.
Offro ad m ode
ESP should normally be operated in normal mode because this
ensures maximum vehicle stabil ity . If necessary, you can activate
the ESP offroad mode by pressing the button
~ page 288, fig. 275
to obtain maxi mum traction and braking abil ity when dr iving off
paved roads at low speeds . In ESP offroad mode , the ESP indicator
l ight ~
page 19 illuminates and the message E S P Offroad appears
briefly in the display.
The ESP offroad mode can be usefu l in the fo llowing exceptional
s ituat ions when slip or a high ly effective differential locking func ­
tion is desirable. Examples:
• when driv ing with t ire chains,
• when driving in deep snow or on loose ground,
Inte llig ent tec hn olo gy
• when driving on uneven surfaces with the wheels severely
unloaded (articulation), and
• when rocking the vehicle loose after it has become stuck .
When the unusual situation is pas t, you should shift back to the
normal ESP operating mode by pushing the button again. The
message
ESP /A SR on then appears briefly in the display.
Hill d escent contr ol
The hil l descent control is swi tched on in ESP offroad mode . When
s lowly descending steep gradients on loose ground or when the
ax les are a rticulated, h ill descent control provides assistance by
automatically applying the brakes to keep vehicle speed constant.
The vehicle is also rendered easier to steer by se lective distribution
of braking force . Hi ll descent control intervenes when:
• the accelerator pedal is not pressed,
• the veh ic le is trave lling less than 12 mph (20 km/hl,
• a steep gradient is detected,
• whee l behavior indicates loose ground or conditions with poor
adhesion (e .g . also axle articulation).
Hi ll descent control operates both driving forward and in reverse.
Active hill descent contro l is deactivated by pressing the accelerator
pedal until the conditions for activat ion a lready listed are met again .
& WARNING
• The Elect roni c Sta bil izati on Progr am is ne ve rt hele ss subject to
th e law s of phy sics. It is particul arly important to pay attention to
t hi s fa ct on we t and slippery ro ads . It i s therefore i mpo rtant th at
yo u a lw ays adapt your dri vin g to the condition of the ro ad and
traffi c conditions . Do n ot allo w the in cre ased sa fety provided by
the Elect roni c Stabili zation Progr am system to lull you into
ac cepting additional safety r isks.
• Please be aw are th at in ESP offroad mo de, parti cularl y on a
s m ooth and slippery road , the wheel s m ay have an incr eased •
I t •

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3g
:t; yL __________________________________________ _
& WARNING (continued)
tendency to spin and the vehicle may break away -danger of skid­
ding!
• Stability is limited in the ESP offroad mode. •
Electronic differential lock (EDL)
The electronic differential lock monitors the rotational
speed of the drive wheels.
General notes
The electronic differential lock (EDU helps the car to start moving,
accelerate and climb a gradient on surfaces providing poor or
almost no grip . Without EDL, this would be difficult, if not impos­
sible.
How the system works
The EDL operates automatically. It monitors the rotational speed of
wheels with the help of the ABS sensors=> page 292. If a noticeable
slip is detected at the wheels (e.g. on slippery ground on one side),
the spinning wheels are braked and power is transferred to the
other wheels. 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
controlled.
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, apply plenty of throttle until the car starts to move.
Overheating of brakes
To prevent the disc brake of the braked wheel from overheating if
subjected to excessive loads on this wheel, the EDL cuts out tempo­
rarily. 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 22. •
Anti-Slip Regulat ion 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 292, ASR monitors the
speed of the driven wheels. If the wheels start to spin, engine torque
is reduced automatically until the tires find enough grip to lock onto
the road surface. The system is active across the entire speed range . ..,

The ASR works in conjunction with the ABS. If a malfunction should
occur in the ABS, the ASR wil l 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 identica l tires. Any differences in rolling radius of the tires can
cause the system to reduce engine power when this is not desired.
See also~
page 359, "New tires and rep lacing tires and wheels". •
Braking
General information
What affects braking efficiency?
Operating conditions and driving habits
The brakes on today's automobiles are still subject to wear,
depending large ly on operating conditions and driving 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
Warranty & Main­
tenance booklet.
Failure to have your brake pads inspected can
result 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 continuously.
Pump the brakes at intervals.
Controls and equip­
ment Safety first Vehicle operation
Intelligent technology
Moisture
or road salt
If you are driving faster than 3 1 mph (50 km/h) and the windshield
wipers are on, the brake pads will briefly touch the brake discs in
regular intervals so as to improve reaction time when braking on
wet surfaces. You, the driver, will not notice anything.
Under certain conditions, for example, when driving 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 careful brake applications sho uld dry off
the brake pads or remove any ice coatings .
The effectiveness of the brakes can be reduced when the vehicle is driven on a salt -covered road and the brakes are not used. Here too,
you should clean off accumulated salt coating from brake discs and
pads with a few carefu l app lications of the brake ~& .
Corrosion
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 for short trips with litt le use of the brakes.
If the brakes are not used frequently, or if corrosion has formed on
t he discs, it is advisable to clean off the pads and discs by braking
firm ly a few times from a moderately high speed~&.
Faults in the brake system
If you shou ld notice a sudden increase in brake peda l trave l, then
one of the two brake circuits may have failed~& .
Low brake fluid le vel
Malfunctions can occur in the brake system if the brake fluid level is
too low . The brake fluid level is monitored electronically .
Brake lining wear status
Brake lining wear may be checked by visual inspection of the condi ­
tion of the brake pads through the openings in the wheel. If neces­
sary, the wheel may be removed for this inspection
~ page 373,
"Changing a whee l" . ._.
Vehicle care Do-it-yourself service Technical data

___ ln_ t _e_ ll-'"ig ...,_ e_ n_t _t_ e_ c_ h _ n_o _ l_o _,.g= y,_ __________________________________________ _
& WARNING
• You should perform braking maneu vers for the purpose of
cleaning the brake system only if road conditions permit . Other
road u sers mu st not be put at r isk -you may cause an a ccident!
• Before des cending a steep grade, reduce speed and shift trans ­
mission into a lower gear or lower dr iving range . Do not ride the
brakes or hold the pedal down too long or too often. This could
cause the brake s to get hot and diminish braking effi ciency .
• Do not "ride the brakes " by resting your foot on the pedal when
you do not intend to b rake. This may cause the br ake s to ove rheat ,
premature wear and increased stopping distance.
• Under ce rtain climat ic and operating condit ions such as
passing through water , driving in heavy rain or after washing the
vehi cle , the effectiveness of the brakes can be reduced . In winter ,
ice can a ccumulate on the brake pads , linings , discs and drums .
Carefully apply bra kes fo r a test . Brakes will dry and ice coatings
will be cleaned off after a few careful brake appli cations .
• Driving for an extended period of time on salt -co vered roads
without using your brakes can also affect braking effic iency. Clean
off accumulated salt coating from brake dis cs and pads with a few
c areful brake applications .
• If you damage the front spoile r, or if you install a different
spoiler, be sure the air flow to the front brakes is not ob structed.
Otherw ise the brake sy stem could overheat reducing the effective­
ness of the entire brake system .
• Failure of one bra ke cir cuit will impair the braking capability
resulting in an increased stopping distance. Avoid driving the
vehicle and ha ve it towed to the nearest authorized Audi dealer or
qualified workshop . •
Brake booster
T he b rake boost er ad ds extra b ra kin g powe r.
The brake booster works with vacuum pressure which is created
o nly w he n t he e ngine is ru nnin g=> & .
& 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 boo ster has somehow been
damaged , the brake pedal must be pressed considerably harder to
make up for the lack of booster assistance . •
Functioning of A!"lt"-Lock Brake System (ABS)
ABS p revents the wheels from locking up unde r brakin g.
Th e ABS co ntribu tes effect ively to vehicle cont ro l since it preve nts
the whee ls from
locking when the brakes are app lied. This means
t h at the ve hicle rema ins steerable and is less l ikely to s kid.
With ABS you do not need to pump the brake . Just hold the brake
pedal down .
However, do not expec t the A BS to s hor ten bra king d istance u nder
all circumstances. When driving o n grave l or on newly fallen snow
o n t op o f icy sur faces, brak ing d istance may be ev en lon ger, the re­
fore, under these c ircumstances, it is especially important that you
driv e slow ly an d with gre at ca re.
How the ABS system works
An a utomatic c heck is m ade w hen a speed of about 1 2 mph (2 0
km/h) is reached. When this happens, a pumping noise can be
h ea rd.

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
extra safety afforded by the ABS tempt you into taking extra risks.
The ABS cannot overcome the laws of physics.
[ i] Tips
• If ABS is not functioning properly , a warning light will come on .
See
=> page 22.
• If a fault occurs in the ABS, the EDL is also not functioning. This
is indicated by the ABS warning light.•
Brake assistant
The 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 quickly , 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 th e brake pedal pressed
until the vehicle has braked to the required speed. The brake assis­
tant swi tches its elf off as soon as you release the brake pedal.
Controls and equip­
ment Safety first Vehicle operation
Intelligent technology
Automatic full braking assist
This function allows full braking
in spite of high brake pedal forces
(e.g . when the brakes are severely stressed because the vehicle is
fully loaded) . The driver notices this function through a reduction of
pedal force and increased pedal travel. When the brake pedal is
released, full braking assist switches off again automatically.
If there is an ABS failure, the brake assistant and automatic full
braking assist ar e not available .
The brake assistant will not be operative if there is a malfunction in
the ABS.
_& WARNING
Please remember that the accident risk always increases if you
drive too fast, especially in corners or on a slippery road, or if you
follow the vehicle ahead of you too closely . Increased risk of an
accident cannot be compensated for even by the brake assistant,
so always maintain a safe speed. iJ
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
comfortable and safe steering response exactly matched to the
vehicle speed.
Power steering will not work if the engine is off. As a result, the
s teering whe el will be hard to turn.
The power steering fluid level is checked during the scheduled
maintenance services .
•
Vehicle care Do-it-yourself service Technical data

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New brake pads
--
Remember that new brake pads do not have a full braking
effect during the first 250 miles (400 kilometers) after they
are installed .
New brake pads have to be "burnished in" before they have optimal
grab =>& .
During the break -in period, you should avoid putting severe loads
on the brakes . Severe loads include, for examp le, sudden hard
braking, in particular at very high speeds or, for example, on moun­
tain passes.
& WARNING
New brake pads don't have the best stopping power and must be
"broken-in" during the initial 100 to 150 miles (150 to 200 kilome­
ters) of normal city driving. You can compensate for this by
pressing the brake pedal more firmly . This also applies later when
new pads are installed.
:J
Catalytic converter
It is very important that your emission control system
(catalytic converter) is functioning properly to ensure that
your vehicle is running in an environmentally sound
manner.
- Always use lead-free gasoline:=> page 325, "Fuel supply".
- Never run the tank down all the way to empty.
- Never put too much motor oil in your engine ==>
page 336,
"Adding engine oil 't=:;r\11
•
Never try to push- or tow-start your vehicle.
The catalytic converter is an efficient "clean-up" device built into the
exhaust system of the vehicle. The catalytic converter burns many
of the po llutants in the exhaust gas before they are released into the
atmosphere.
The exclusive use of unleaded fuel is critically important for the life
of the catalytic converter and proper functioning of the engine.
& WARNING
• Do not park or operate the vehicle in areas where the hot
exhaust system may come in contact with dry grass, brush, fuel
spill or other material which can cause a fire .
• Do not apply additional undercoating or rustproofing on or
near the exhaust manifold, exhaust pipes, catalytic converter or
heat shields. During driving, the substance used for undercoating
could overheat and cause a fire .
0 Note
• Be aware that just one tank filling with leaded fuel will alr eady
seriously degrade the performance of the catalytic converter.
• Do not exceed the correct engine oil level=>
page 336.
• Do not drive until the fuel tank becomes completely empty. The
engine could misfire. Unburned fuel could also get into the exhaust
system and this could cause the catalytic converter to overheat.
• Do not turn off the ignition while the vehicle is moving.
• Do not continue to operate your vehicle under these conditions,
as otherwise fuel can reach the catalytic converter. This could result
in overheating of the converter, requiring its replacement .
• To assure efficient operation of the Emission Control System:
- Have your vehicle maintained properly and in accordance with
the service recommendations in your Warranty
& Maintenance
booklet. •

- Lack of proper maintenance as wel l as improper use of the
vehic le wi ll impair the func tion of the emission con tro l system
and could lead to damage.
<£> For the sake of th e envir onm ent
Even when the Emission Control System is operating properly, the
exhaust gas can have a su lfur -like exhaust gas smell 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 spoi lers 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 limitations
Controls and equip­
ment Safety first Vehicle operation
Dri
ving and environm ent
If you anticipate what you need to do next and drive economica lly,
you can easily cut your fuel consumption 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 estimates as published by ENV IRONMENTAL
PRO TEC TION AGENCY (EPA) and Transport Canada may not corre ­
spond to your actua l consumption on the road, which wi ll vary
depending upon vehic le 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 accelerat ing and braking.
Vehicles use the most fuel 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 max imum speed.
Acce lerating gently reduces fue l 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 approximate ly
three quarters of top speed, fuel consumption wil l be reduced by
Vehicle care Do-it-yourself service Technical data

lffll __ D_ r_ iv _i_ n-' g"'""'- o_ ff_ r_ o _ a_ d __________________________________________________ _
-Drive only on roads and offroad sections which match
the design of your vehicle and your abilities as a driver .
Never take risks!
Drive slowly and plan ahead!
Take into consideration the
ground clearance of your
vehicle.
- Activate the
ESP offroad mode=:> page 288 as needed.
- Use t he
hill descent control=:> page 289 when driving
down steep sections on hills.
Unpaved roads and offroad
Drive slowly on unfamiliar roads and unknown offroad sections, and
look out for unexpected obstac les (e.g . potholes, rocks, tree stumps,
etc.).
To prevent the vehicle from bottoming and avoid damage to the
underbody, you should drive straight across severe bumps in the
ground with on ly one side of the vehicle so that on ly two of your
whee ls cross the bumps .
Dr ive briskly through sandy or marshy offroad sections and do not
stop, if at all possible.
Driving through water
Your vehicle can drive through standing water if the ground is firm
enough . The
maximum fording depth is 19 .7 in or 500 mm (vehic les
without air springs) or 21.1 in or 535 mm (vehicles with adaptive air
suspension*, at high level 2).
Check the depth of the water before driving through water .
Cross water only at walking speed, do not stop and do not turn the
engine off .
If you drive fast through the water, you wi ll create a bow wave in
front of the vehic le. This bow wave can get into the engine air intake
and severe ly damage the engine. Avoid driving through salt water (corrosion)
.
Driving on a slope
If you ever find yourself not able to climb a slope, do not try to turn
around, drive back down in
reverse. Otherwise, you run the risk of
tipping over.
If the vehicle threatens to tip over when driving across a slope, you
must immediately steer downhill in the direction of the slope.
Do not park your vehicle on steep slopes or grades.
To reduce the risk of tipping over, drive on slopes in the direction of
the downward slope (fall line) -
not crosswise .
Driving on snow-covered ground
The standard tires fitted to your vehicle are not snow tires. So you
should mount wheels with snow tires in good time where winter
road conditions prevail. Before driving on unploughed stretches of
deep snow, install tire chains. For technical reasons, tire chains may
only be installed on the rear whee ls -never on the front wheels .
L1}. WARNING
After driving through water, mud, slush, etc. the brakes may be
slow to take effect because of wet brake rotors and pads . The
brakes must first be carefully dried by braking so that full braking
effect is restored. •