brake AUDI RS5 CABRIOLET 2015 Workshop Manual

204 Checking and filling
Brake fluid
Checking brake fluid level
The brake fluid level can be checked with a
quick glance .
N N ~ N
" (X) (0
Fig. 179 Engine compartme nt: Cover on the brake flu ·
id reservo ir
Before you check anything in the engine com­
partment,
a lwa ys re ad and heed all WARN·
ING S ¢.&._ in Working in the engine compart­
ment on page 195 .
.. Read the brake fluid level from the brake
fluid reservoir
¢ fig . 179 , ¢page 197,
fig . 174.
The brake fluid level must be be ­
tween the "MIN" and
"MAX" markings.
The brake fluid reservoir is located at the rear
partition of the engine compartment on the
left side
¢ page 197.
The fluid level may drop slightly after some
time due to the automatic adjustment of the
brake pads. This is not cause for alarm.
If the brake fluid level falls
considerably be­
low the "MIN" mark, the brake warning/indi­
cator light (U.S. models:
11111 , Canadian
models :. ) will come on
¢page 15. Do not
continue to operate the vehicle. The complete brake system should be thoroughly checked
by an authorized Audi dealer or qualified
workshop and the cause corrected .
If the
brake fluid level is too low, the brake warn ing/
indicator light w ill illuminate. Contact an au­
thorized Audi dealer
immedi atel y.
@ Tips
The brake fluid reservoir is located under­
neath the cover.
Changing brake fluid
Have the brake fluid changed by an experi­
enced technician .
Brake fluid absorbs moisture from the air. If
the water content in the brake fluid is too
high, corrosion in the brake system may result
after a period of time . The boiling point of the
brake flu id will also decrease conside rably and
decrease braking pe rformance.
Therefore, the brake fluid must be changed
every two year s. Always use new brake flu id
which conforms to Federal Motor Veh icle
Standard "F MVSS 116 DOT 4".
The brake fluid reservoir can be diff icult to
reach, therefore, we recommend that you
have the brake fluid changed by your author­
ized
Audi d ealer . Your dealer has the correct
tools, the right brake fl uid and the know -how
to do this for you .
A WARNING
- Brake fluid is poisonous . It must be stor­
ed only in the closed original container
out of the reach of children!
- Brake failure can resu lt from o ld or inap­
propriate brake flu id. Observe these pre­
cautions:
- Use only brake f luid that meets SA E
specifica tion
J 1 7 03 and conforms to
Federa l Moto r Ve hicle Standard 1 16.
Always check with yo ur authorized Aud i
dealer to make sure yo u are using the
correct brake fluid. The correct type of brake f lu id is also indicated on the
brake fluid reservoir.
- The brake fluid must be new. Heavy use
of the brakes can cause a vapor lock if
the brake fluid is left in the system too
l ong. This can seriously affect the effi­
c iency of the brakes as well as your
safety. This cou ld resu lt in an accident.
(D Note
Brake fluid will damage the paint of your
vehicle .

M N
er
u..
co ,...., \!) 1.1'1 ,...., 1.1'1 ,....,
@ For the sake of the environment
Because of the pr oblem of proper d isposa l
of brake flu id as we ll as the special tools
requ ired and the necessary expert ise, we
recommend that you have the brake fluid
changed by your author ized Audi dealer .
Battery
General information
Under normal operating conditions, the bat­
tery in your Audi does not need any mainte ­
nance. With
high outside temperatures or
long daily dr ives we recommend that you have
the electro lyte level checked by an authorized
Aud i dealer or qualified workshop . The elec­
trolyte leve l should also be checked each time
the battery is charged c>
page 207.
Have the battery checked when you take your
ve hicle in for service . You are well adv ised to
replace a battery that is older than 5 yea rs .
W ith certa in types of a irbag deployment, t he
battery is d isconnected from the vehicle elec­
tr ica l system for safety reasons c>
.&. in Re­
pair, care and disposal of the airbags on
page 144.
Disconnecting the battery terminals
Some vehicle functions (power w indow regu­
lators, for example) are lost if the battery ter­
m inals a re d isconnected. These func tions have
to be re lea rned after the batte ry term inals a re
connected agai n. T o prevent this, the bat tery
should only be d isconnec ted from the vehicle
e lec tric al system when absolu tely necessa ry
for repairs .
Vehicles not driven for long periods
If you do not drive you r vehicle over a period
of severa l days or weeks, elec trical compo­
nen ts are gr adually cut b ack o r swi tched off .
This redu ces energy cons umption and main­
tains starting capab ility over a longer per io d
c> page 177.
Some o f the conven ience f unctions m ay not
ope rate, su ch as the in ter ior lig hts or t he
Checkin g and fillin g 205
power seat adjus tment. The convenience
funct io ns w ill be available again when yo u
turn o n the ign ition and start the engine.
Winter operation
D ur ing the w inte r mon ths, bat tery capa city
tends to dec rease as tempera tures drop . This
is beca use more power is a lso consumed wh ile
starting, and the headlights, rear window de­
fogger, etc., are used more often.
Avoid unnecessary powe r consumpt ion, pa r­
ticular ly in city traffic or when traveling only
sho rt distances. Let yo ur authorized A udi
dealer check the capacity of the vehicle bat ­
tery before w inter sets inc>
page 207. A well
charged battery will not on ly prevent starti ng
problems w hen the weather is cold, but w ill
also last longer.
@ Tips
If your vehicle is left standing for seve ral
weeks at extremely low temperatures, the
vehicle battery s hou ld be removed and
stored where it will not freeze . This will
p revent it from be ing damaged and having
to be repla ced.
Working on the battery
Be especially careful when working on or near
the bat tery.
The battery is located in the luggage compar t­
ment under the floor . B efo re you che ck any­
thi ng in the luggage compartment,
read and
heed all WARNINGS
c> ,&. .
Always heed the safety warnings , when work­
i ng on the veh icle batte ry or t he vehicle e lec­
t rical sys tem to p reven t inju ry.
The following WARNINGS are very
important when working on the battery:
Always heed the following WARNING SYM· BO LS and safety precautions when working
on the battery .
®
Always wear eye protection.
•
•

210 Tires an d whee ls
Tires and wheels
Tires
General notes
Tires may be the least appreci­
ated and most abused parts of
a motor vehicle.
Ti res may be the least appreci­
ated and most abused parts of
a motor vehicle. Tires are, how­
ever, one of the most important
parts of a vehicle, particularly
considering the comparatively
small patch of r ubber on each
tire that assures that all-impor­
tant contact between you, your
vehicle and the road.
Maintaining the co rrect tire
p ressure, making sure that your
vehicle and its tires do not have
to carry more we ight than they
can safe ly handle, avoiding
damage from road hazards and
regularly inspecting tires for
damage including cuts, s lashes
irregular wear and overall con ­
d ition are the most important
things that you can do to help
avoid sudden tire failure inc lud­
ing tread separation and blow­
outs.
Avoiding damage
If you have to drive over a curb
or similar obstacle, drive very
slowly and as close as possible
at a right angle to the curb.
Always keep chemicals includ­
ing grease, oil, gasoline and
brake fluid off the tires.
Inspect the tires regularly for
damage (cuts, cracks or blis­
ters, etc.). Remove any foreign
bodies embedded in the treads.
Storing tires
Mark tires when you remove
them to indicate the direction
of rotation. This ensures you to be able to mount them correct ­
ly when you reinstall them.
When removed, the wheels or
tires should be stored in a cool,
dry and preferably dark p lace.
Store tires in a vertical position if they are not mounted on
rims, in a horizontal position if
they are mounted on rims.
New tires
New tires have to be broken in
¢ &.
The tread depth of new tires
may vary, according to the type .,.

212 Tires and wheels
-If you notice unusual vibra­
tion or if the vehicle pulls to
one side when driving, al­
ways stop as soon as it is
safe to do so and check the
wheels and tires for dam­
age.
0 Note
-Please note that summer and winter tires are de­
signed for the conditions
that are typical in those sea­
sons. Audi recommends us­
ing winter tires during the
winter months. Low tem­ peratures significantly de­
crease the elasticity of
summer tires, which affects
traction and braking ability. If summer tires are used
in
very cold temperatures, cracks can form on the tread
bars, resulting in perma­
nent tire damage that can
cause loud driving noise and
unbalanced tires. Audi is not
responsible for this type of
damage.
-Burnished, polished or chromed rims must not be used in winter road condi­
tions. The surface of the
rims does not have suffi­
cient corrosion protection
for this and could be perma­
nently damaged by road salt
or similar substances.
Glossary of tire and loading terminology
Accessory weight
means the combined weight (in
excess of those standard items
which may be replaced) of auto­ matic transmission, power
steering, power brakes, power
windows, power seats , radio,
and heater, to the extent that
these items are available as fac­
tory-installed equipment (whether installed or not).
Aspect ratio
means the ratio of the height to
the width of the tire in percent.
Numbers of 55 or lower indi­
cate a low sidewall for im­
proved steering response and
better overall handling on dry
pavement.
...

214 Tires and whee ls
Ma ximum load r ating Overall width
means the load rating for a tire means the linear distance be-
at the maximum permissible in- tween the exteriors of the side-
flation pressure for that tire. walls of an inflated tire, includ -
Max imum lo ad ed vehicle ing elevations due to labeling,
weight decorations, or protective
means the sum of: bands or ribs
.
(a) Curb weight
Ply
(b) Accessory weight means a layer of rubber
-coated
(c) Vehicle capacity weight, and parallel cords
.
(d) Production options weight
Production options weight
Ma ximum (permissible )
means the combined we ight of
inflation pressure those installed regular produc-
means the maximum cold infla- tion options weighing over 5
tion pressure to which a tire lbs
. (2 .3 kg) in excess of those
may be inflated. Also called standard
items which they re-
"maximum inflation pressure." place, no
t previously consid-
Normal occupant weight
ered in curb weight or accessory
weight, including heavy duty
means 150 lbs. (68 kilograms) brakes, ride levelers, heavy duty
times the number of occupants battery, and special trim.
seated in the vehicle up to the
Radial ply tire total seating capac ity of your
vehicle . means a pneumatic tire in
Occupant distribution
which the p
ly cords that extend
to the beads are laid at s ub-
means distribution of occu -
stantially 90 degrees to the
pants in a vehicle .
centerline of the tread.
Outer diameter
Recommended inflation
means the overall diameter of pressure
an inflated new tire.
see c::> page 213, Cold tire infla-
tion pressure .
~

220 Tires and wheels
Because technical changes may
be made to vehicle equipment
during the model year, always
compare the tire size designa­
tion on the tire pressure label
on your vehicle with the tires on
your vehicle. Make sure that the
tire size information on the ve­ hicle label is the same as the
size of the tires on the vehicle.
This is especially important if
the vehicle belongs to someone else or you bought the vehicle
with different rims/tires or you
bought the vehicle as a previ­
ously owned vehicle.
Remember, your safety and
that of your passengers also de­ pends on making sure that load
limits are not exceeded . Vehicle
load includes everybody and ev­
erything in and on the vehicle.
These load limits are technical­
ly referred to as the vehicle's
Gross Vehicle Weight Rating
("GVWR"). The Gross Axle
Weight Rating ("GAWR") is the
maximum load that can be ap­
plied at each of the vehicle's
two axles . The Gross Vehicle
Weight Rating and the Gross
Axle Weight Rating are listed on the safety compliance stick- er label located on the driver's
side B-pillar.
The tire pressure
label on your Audi lists the
maximum combined weight of
all of the occupants and lug­
gage or other cargo that the ve­
hicle can carry. For the location
of the tire pressure label
¢fig. 182.
&_ WARNING
-
Overloading a vehicle can
cause loss of vehicle control,
a crash or other accident, se­ rious personal injury, and
even death .
-Carrying more weight than
your vehicle was designed to carry will prevent the ve­
hicle from handling properly
and increase the risk of a
loss of vehicle control.
-The brakes on a vehicle that has been overloaded may
not be able to stop the vehi­
cle within a safe distance.
-Tires on a vehicle that has
been overloaded can fail
suddenly causing loss of
control and a crash.
-Always make sure that the
total load being transported
- including the weight of a

226 Tires and wheels
The tire pressure label on your
Audi also lists the maximum
combined weight of all of the
occupants and luggage or other
cargo that the vehicle can carry. For the location of the label
¢page 217, fig. 182.
A WARNING
-
Overloading a vehicle can
cause loss of vehicle control,
a crash or other accident, se­
rious personal injury, and
even death.
-Carrying more weight than your vehicle was designed to carry will prevent the ve­
hicle from handling properly
and increase the risk of the
loss of vehicle control.
-The brakes on a vehicle that has been overloaded may
not be able to stop the vehi­
cle within a safe distance.
-Tires on a vehicle that has
been overloaded can fail
suddenly, including a blow­
out and sudden deflation,
causing loss of control and a
crash .
-Always make sure that the
total load being transported
- including the weight of a trailer hitch and the tongue
weight of a loaded trailer­ does not make the vehicle
heavier than the vehicle's
Gross Vehicle Weight Rat­
ing.
Determining correct load
limit
Use the example below to cal­
culate the total weight of the
passengers and luggage or oth­
er things that you plan to trans­
port so that you can make sure
that your vehicle will not be
overloaded.
Steps for Determining
Correct Load Limit
1. Locate the statement "THE
COMBINED WEIGHT OF OC­
CUPANTS AND CARGO
SHOULD NEVER EXCEED XXX KG OR XXX LBS"on your vehi­
cle's placard (tire inflation
pressure label)
¢page 217,
fig. 182.
2. Determine the combined
weight of the driver and pas­
sengers that will be riding in
your vehicle.
...

M N
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co ,...., \!) 1.1'1 ,...., 1.1'1 ,....,
wear on steering, suspension and tires. A wheel must also be
rebalanced when a new tire is
installed.
Incorrect wheel alignment
Incorrect wheel alignment can
cause excessive tire wear, im­
pairing the safety of the vehi­
cle. If tires show excessive
wear, have the wheel alignment checked by an authorized Audi
dealer or qualified workshop.
All wheel drive
Vehicles with quattro must al­
ways have tires of the same
size, construction and tread
type. For details see
¢page 176.
A WARNING
Sudden tire failure can lead
to loss of control, a crash and serious personal injury!
-Never drive a vehicle when the tread on any tire is worn down to the wear indica­
tors.
-Worn tires are a safety haz­
ard, they do not grip well on
wet roads and increase your risk of "hydroplaning" and
loss of control.
Tires and wheels 229
-Always keep chemicals that can cause tire damage, such
as grease, oil, gasoline and
brake fluid away from tires.
-Tires age even if they are not being used and can fail
suddenly, especially at high speeds. Tires that are more
than 6 years old can only be used in an emergency and
then with special care and
at lower speeds.
-Never mount used tires on your vehicle if you are not sure of their "previous histo­
ry." Old used tires may have
been damaged even though
the damage cannot be seen
that can lead to sudden tire
failure and loss of vehicle
control.
•
•
'

Tires and wheels 235
-Overloading tires cause heat Incorrect use of run flat •
build-up, sudden tire fail- tires can lead to vehicle • '
ure, including a blowout damage or accidents. Check
and sudden deflation and with an authorized Audi loss of control. dealer or tire specialist to
-Temperature grades apply see if your vehicle
can be
to tires that are properly in- equipped with run flat tires.
flated and not over or un- If run flat tires are used,
derinflated. they must be installed on all
-For technical reasons it is four wheels. Mixing tire
not always possible to use types is not permitted.
wheels from other vehicles -
(D Note
in some cases not even -For technical reasons, it is
wheels from the same vehi-
not generally possible to
cle model.
use the wheel rims from
-If you install wheel trim
other vehicles. This can hold
discs on the vehicle wheels, true for wheels of the same
make sure that the air flow vehicle type.
to the brakes is not blocked. -If a replacement tire is dif-
Reduced airflow to the
ferent from the tires that
brakes can them to over-
you have mounted on your
heat, increasing stopping
vehicle (for example winter
distances and causing a col-
tires or wide profile tires),
lision.
-Run flat tires may only be then use the replacement
tire for a short period of
used on vehicles that were time only and drive with ex-
equipped with them at the tra care. Replace the flat
factory. The vehicle must
tire with the tire matching
have a chassis designed for
the others on your vehicle
run flat tires and a factory-
as soon as possible.
installed tire pressure moni-
M
-Never drive without the N
er toring system* that indi-u.. co
valve stem cap. The valves ,....,
cates a loss of tire pressure. \!) 1.1'1 ,...., could get damaged. 1.1'1 ,....,

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~ Engage th e pa rkin g bra ke to p revent your
v eh icl e from ro lling unintentionally ¢,&. .
~ Move the sele ctor le ve r to the P po siti on.
~ Take the jack c> page 242 out of the l uggage
compartment .
_& WARNING
You or your passengers cou ld be injured
wh ile changing a wheel if you do not fol­
low t hese safety precautions :
-If you have a flat t ire, move a safe dis­
tance off the road. Turn off the eng ine,
tu rn the emergency flashers o n and use
othe r warning dev ices to alert o ther mo­
torists.
- Make su re that passengers wai t in a safe
place away from the vehi cle and well
away from the road and traff ic.
- T o help p revent the veh icle from mov ing
sudden ly and possibly slipping off the
jack, a lways fully set the parking brake
and block the whee l diagona lly opposite
the wheel being changed with the fo ld­
ing chocks or other objects. When one
front wheel is lifted off the ground, plac­ ing the Automat ic Transm iss ion in "P"
(Park) w ill
not prevent the vehicle from
moving.
- Before you change a wheel, be sure the ground is level and firm. If necessa ry,
use a sturdy board under the jack.
- Always store the vehicle tool kit , the
jack* and the replaced ti re in the luggage
compartment
c> page 118.
([) Note
If you are chang ing the wheel on a steep
incline, use a rock or similar object to
b lock the opposite whe el to prevent the
veh icle from mov ing.
Obey all laws.
What do I do now? 245
Changing a wheel
When you change a wheel , follow these­
quence described below step-by-step and in
exactly that order.
l. Remove the w heel bolt cap s* . For more
details see also
c> page 246, Wheels with
wheel bolt caps .
2. Loosen the wheel bolts .:>page 246.
3. Locate the p roper mounting point fo r the
jack and align the jack below that point
.:> page 247 .
4. Lift the car with the jack Q page 247 .
5. Remov e the wheel with the flat tire and
then install the other wheel
c> page 248.
6. Tig hten all wheel bolts lightly.
7.
Lower the vehicle with the jack .
8 . Use the wheel bolt w rench and
firmly
t ighten all wheel bolts in a crisscross pat­
te rn
Q page 246.
9. Replace the whe el bolt cap s*.
WARNING
A lways read and fo llow all WARN INGS and
information
Q .&. in Raising the vehicle on
page 247
and ¢ page 249 .
After changing a wheel
A wheel change is not complete without the
doing the following .
~ Always store the vehicle tool kit, t he jack*,
and the rep laced tire in the lugg age com­
par tment
Q page 118.
~ As soon as possib le, have the t ight ening
torque s
on all wheel bolts checked with a
torque w rench. The correct tightening to r­
que is 90 ft lbs. (120 Nm).
~ Have the flat tire replaced as soon as possi­
ble.
(D Tips
- If you not ice that the wheel bolts are
corroded and diff icult to turn while
chang ing a tire, they should be replaced
before you check the tightening torque . •
•