brake AUDI A6 2018 Service Manual

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0 0 <..:l ' On Board Diagnostic
System (OBD)
The On-Board Diagnostic System monitors the
engine and transmission components that influ­
ence emissions.
F ig . 176 Footwell o n le ft s ide of th e vehicle: con nectio n
port fo r th e On -Board Diagnostic System (OBD)
On -Board Diagnostic S ystem
Eng ine data can be read out at the On-Board Di ­
agnostic System connection port using a special
testing device
r::;, fig . 176.
Ind icat or light
If thE' ¢..ift indicator light blinks or turns on, there
is a malfunction that is causing poor emissions
quality and that could damage the catalytic con­
verter .
Drive s lowly to an authorized Audi dealer or au­
thor ized Audi Service Facility to have the mal­
function corrected .
The indicator light can also turn on if the fuel fill­
er cap is not closed correct ly
c::;, page 186.
A WARNING
Incorrect use of the connection port for the
On-Board Diagnostic System can cause mal­
functions, which can then result in acc idents
and ser io us injuries .
- Only allow an author ized Audi dealer or au­
thorized Aud i Serv ice Facility to read out the
engine data.
-
Chec king and Filling
Engine compartment
Working in the engine compartment
Special care is required if you are working in the
engine compartment
For wo rk in the engine com part ment , such a s
che cking and filling fluids, there i s a ris k of i n­
jur y, sc alding, a cci dent s, and b urn s. For t his
r easo n, foll ow all the w arnings and g en e ral
s afe ty pre ca ution s pro vided in the f ollowing
in ­
formati on. Th e engine compartm ent i s a dan­
ge rou s area in the vehicle .
r::;, &..
A WARNING
-Turn the engine off.
- Sw itch the ignition off.
- Set the parking brake.
- Select the "P" selector lever position .
- Let the eng ine cool down .
- Never open the hood when there is steam or
coolant escaping from the engine compart­ ment, because there is a risk that you could
be burned . Wait unt il no steam or coolant is
escaping.
- Keep children away from the eng ine com­
partment .
- Never sp ill fluids on a hot engine. These flu­
ids (such as the freeze protection contained in the coolant) can catch fire.
- Avoid short c ircuits in the electrical system .
- When working in the engine compartment,
remember that the radiator fan can switch
on even if the ignition is switched off, which increases the ris k of personal injury .
- Never open the cap on the coolant expan­
sion tank when the engine is warm . The
coo ling system is under pressure.
-To protect your face, hands, and arms from hot steam or coolant, cover the cap with a
large cloth when opening .
- Do not remove the eng ine cover under any
circumstances . This increases the risk of
bu rns .
- If tests need to be performed with the en­
g ine runn ing, there is add it iona l danger due
to mov ing components (such as the ribbed
~
1 8 9

Checking and Filling
belt, alternator and radiator fan) and from
the high-voltage ignition system.
- Do not under any circumstances give gas in­
advertently (for example, by hand from the
engine compartment) if the vehicle is sta­
tionary but the engine is running and a gear
is engaged. Otherwise, the vehicle will start
to move immediately and this could result
in an accident.
- Pay attention to the following warnings list­
ed when work on the fuel system or on the
electrical equipment is required.
- Do not smoke.
- Never work near open flames.
- Always have a working fire extinguisher
nearby.
- All work on the battery or electrical system
in your vehicle can result in injuries, chemi­
cal burns, accidents or burns. Because of
this, all work must be performed
only by an
authorized Audi dealer or authorized Audi
Service Facility.
- To reduce the risk of electric shock and in­
jury, never touch the following components when the engine is running or is being start­
ed:
- Ignition cable
- Other components in the electronic high-
voltage ignition system
- If you must check or perform work on the
engine while it is running:
- Set the parking brake and place the selec­ tor lever in the P (park) position first.
- Always proceed with extreme caution so that clothing, jewelry or long hair do not
become caught in the radiator fan, fan
belt or other moving components or do
not come into contact with hot compo­
nents. Tie back long hair before beginning
work and do not wear clothing that can
hang down into the engine.
- Limit your exposure to exhaust and chemi­
cals to as short a time as
possible~ &..
A WARNING
California Proposition 6S Warning:
190
-Engine exhaust, some of its constituents,
and certain vehicle components contain or
emit chemicals known to the State of Cali­
fornia to cause cancer and birth defects and
reproductive harm . In addition, certain flu­
ids contained in vehicles and certain prod­
ucts of component wear contain or emit
chemicals known to the State of California
to cause cancer and birth defects or other
reproductive harm.
- Battery posts, terminals and related acces­
sories contain lead and lead compounds,
chemicals known to the State of California
to cause cancer and reproductive harms.
Wash hands after handling.
@ Note
When filling fluids, be sure not to mix the flu­
ids up. Otherwise severe malfunctions and en­
gine damage will occur.
@ For the sake of the environment
You should regularly check the ground under
your vehicle in order to detect leaks quickly. If there are visible spots from oil or other fluids, bring your vehicle to an authorized Audi deal­
er or authorized Audi Service Facility to be
checked.

Checking and Filling
Engine compartment overview
The most important check points.
Fig. 179 Typical location of the rese rvoir and the engine o il filler open ing
(D Jump start point(-) with hex head screw
~page 198, ¢page 239
@ Jump start point(+) under the cover
~ page 198, ¢ page 239
® Engine oil label* with VW standard
¢page 192
@ Brake fluid reservoir ((0)) ¢page 197
® Eng ine oil filler opening(~)¢ page 194
@ Coolant reservoir ( - L) ~ page 196
(j) Washer fluid reservoir (0) ¢ page 199
The engine oil filler opening ® may be located in
a different area depending on the specific engine.
& WARNING
Read and follow all WARNINGS before check­
ing anything in the engine
compartment¢ &
in Working in the engine compartment on
page 189.
192
Engine oil
If the engine oil level is too low
If you need to add engine oil, use an oil that is
listed on the sticker.
The sticker is located at the
front of the eng ine
compartment¢ page 192,
fig . 179 .
If the recommended engine oil is not availab le,
in an emergency you may add a maximum of 1
quart(! liter) of ACEA C3 or API SN eng ine oi l
one time until the next oil change .
For more information on the correct eng ine oil
for your vehicle, contact an authorized Audi deal­
er or authorized Aud i Serv ice Facility . Have the oil
c h anged by an authorized Audi dealer or author­
ized Service Facility.

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0 0 <..:l ' Brake fluid
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Fig. 182 Eng ine compartment: cap on brake fluid reservoir
Observe the safety precautions ~.&. in Working
in the engine comportment on page 189.
Checking th e brake fluid level
• Read the brake fluid level on the brake fluid
reservo ir
<=) page 192, fig. 179. The brake fluid
level must be between the MIN and MAX mark­
ings ~,&. .
The brake fluid level is mon itored automat ically.
Changing the bra ke flu id
Have the brake fluid changed regularly by an au­
thorized Audi dealer or authorized Audi Service
Facility .
A WARNING
-If the brake fluid level is be low the MIN
marking, it can impair the braking effect
and dr iving safety, which increase the risk of
an acc ident. Do not cont inue driv ing . See an
au thorized Audi deale r or autho rized Aud i
Service Facility for assist ance .
-If the brake f luid is o ld, bubbles may form
in the b rake system d uring heavy b raking.
T his would impair bra king perfo rman ce an d
driving safety, which increases the risk of an
accident.
- T o ensure the bra ke system functions cor­
rectly, only use brake fluids that comply
with VW standard 50114 or FMVSS-116 DOT 4 .
(D Note
-If the brake fluid level is above the MAX
mar king, brake fluid may leak out over the
Chec king and Filling
edge of the reservo ir and result in damage
to the vehicle.
- Do not get any b rake fl uid on the vehicle
paint, because it wi ll co rrode the paint .
Battery
General warnings about batteries
Because of the complex power supp ly, alt work
o n batter ies such as d isconnecting, replacing,
etc., sho uld
onl y be performed by an au tho riz ed
Audi dealer or au thori zed A udi Se rvice Fac ility
Q A .
The term "vehicle battery" refe rs to the 12 Volt
batte ry in you r vehicle.
Detail ed warnings for the vehicle battery :
Always wear eye protection .
&
Battery acid is highly corrosive. A lways
wear protective gloves and eye protection .
.
®
Fire, sparks, open flame and smoking are
forbidden .
A
A highly explosive mixture of gases can
form w hen cha rging bat ter ies.
®
Always keep children far away from bat-
tery electrolyte and the battery.
~
Always follow the ins tructio ns in the ope r-
ating manual.
A WARNING ~
A ll work on the battery or electrical system in
your vehicle can result in injuries, chemica l
bu rns, acc idents or burns. Because of this, all
work must be performed
only by an author­
i zed Audi dealer or authorized Audi Service
Fac ility .
A WARNING
-Ca lifo rnia Proposition 65 Warning:
- Battery posts, term inals and related acces­
sories contain le ad and lead com pou nds,
ch emi cals known to the Sta te of Californ ia
to cause cancer and reproductive prob lems.
Was h hands after handling.
197

Wheel s
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 steer­
ing , power brakes , power win­
dows , power seats, radio, and
heater, to the extent that these
items are available as factory-in­
stalled equipment (whether in­
stalled or not).
Aspect ratio
means the ratio of the height to
the width of the tire in percent. Numbers of 55 or lower indicate a
low sidewall for improved steer­
ing response and better overall
handling on dry pavement .
Bead
means the part of the tire that is
made of steel wires, wrapped or
reinforced by ply cords and that is
shaped to fit the rim.
Bead separation
means a breakdown of the bond
between components in the bead.
20 4
Cord
means the strands forming the
plies in the tire.
Cold tire inflation pressure
means the t ire pressure recom­
mended by the vehicle manufac­
turer for a tire of a designated
size that has not been driven for
more than a couple of miles (kilo ­
meters) at low speeds in the
three hour period before the tire pressure is measured or adjusted.
Curb weight
means the weight of a motor ve­
hicle w ith standard equipment in­
cluding the maximum capacity of
fuel, oil, and coolant, ai r condi­
tioning and additional weight of
optional equipment.
E x tra load ti re
means a tire designed to operate
at higher loads and at higher in­
flation pressures than the corre­
sponding standard tire. Extra load
tires may be identified as "X L",
"
l" "EXTRA LOAD" or "RF" on X I I
the sidewall. .,.

Wheels
Production options we igh t
means the combined weight of
those installed regular production
options weighing over 5 lbs.
(2.3 kg) in excess of those stand­
ard items which they replace, not previously considered in curb
weight or accessory weight, in­
cluding heavy duty brakes, ride levelers, roof rack, heavy duty
battery, and special trim.
Radial pl y tir e
means a pneumatic tire in which
the ply cords that extend to the beads are laid at substantially
90 degrees to the centerline of
the tread.
R ecomm ended in flation
pressure
see ¢ page 204 , Cold tire infla­
tion pressure.
R einforced tire
means a tire designed to operate
at higher loads and at higher in­
flation pressures than the corre­
sponding standard tire . Rein ­
forced tires may be identified as
"XL" "xl" "EXTRA LOAD" or "RF" , , ,
on the sidewall.
206
Rim
means a metal support for a tire
or a tire and tube assembly upon
which the tire beads are seated.
Rim diam eter
means nominal diameter of the
bead seat . If you change your
wheel size, you will have to pur ­
chase new tires to match the new rim diameter .
Rim size designation
means rim diameter and width.
Rim width
means nomina l distance between
r im
flanges .
Sidewall
means that portion of a tire be­
tween the tread and bead .
Speed rating (letter code )
means the speed at which a tire is
designed to be driven for extend­
ed periods of time. The ratings range from 93 mph (150 km/h)
to
186 mph (298 km/h) ¢ table
on page 202 .
You may not find
this information on all tires be­
cause it is not required by law .
The speed rating letter code,
where applicable, is molded on
the tire sidewall and indicates the
...

Wheels
-Only use tires that are more than six years old when abso­lutely necessary and drive
carefully when doing so.
-Do not use run-flat tires on your vehicle. Using them when not permitted can lead to
ve­
hicle damage or accidents.
-If you install wheel covers on the vehicle, make sure they al­low enough a ir circulation to
cool the brake system. If they
do not, this could increase the risk of an accident.
Tire wear/damage
Fig. 186 Tire profile: trea dwear indica ­
tor
Tire wear
Check the tires regularly for wear.
-Inflation pressure that is too low
or high can increase tire wear
considerably.
l) Obey any applicable regulations in your
country.
210
-Driving qu ickly through curves,
rapid acceleration and heavy
braking increase tire wear.
-Have an authorized Audi dealer or authorized Audi Service Facili­
ty check the wheel alignment if
there is unusual wear.
-Have the wheels rebalanced if an imbalance is causing noticeable
vibration in the steering wheel. If you do not, the tires and other
vehicle components could wear more quick ly.
Treadwear indicator
Original equipment tires contain
treadwear indicators in the tread pattern, which are bars that are 1/16 in (1.6 mm) high and are
spaced evenly around the tire per­ pendicular to the running direc­
tion
c> fig . 186. The letters "TWI"
or triangles on the tire sidewall indicate the location of the tread­
wear indicators.
The t ires have reached the mini­
mum tread depth
l) when they
have worn down to the treadwear
indicators. Replace the tires with
new ones
c> A . "'

0 0)
A WARNING
Overloading a vehicle can cause
loss of vehicle control, a crash
or other accident, serious per­
sonal injury, and even death .
- Carrying more weight than
your vehicle was designed to
carry will prevent the vehicle
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 vehicle
within a safe distance .
- Tires on a vehicle that has
been overloaded can fail sud­
denly, including a blowout and
sudden deflation, causing loss
of control and a crash .
- Always make su re that the to­
tal load being transported - inc lud ing the weight of a trail­
er hitch and the tongue
weight of a loaded trailer -
does not make the vehicle
heavier than the vehicle's
Gross Vehicle We ight Rating.
Determining correct load
limit
~ Use the example below to calcu-
"' 8 late the total weight of the pas­s ..
Wheels
sengers and luggage or other
things that you plan to transport so that you can make sure that
your vehicle will not be overload­
ed .
Steps for Determining Correct
Load Limit
1 . L ocate the statement "THE
COMB INED WEIGH T OF OCCU­
P ANTS AND CARGO S HOU LD
N EVER EXCEED XXX KG OR XXX
L BS " on your vehicle's placard
(tire inflation pressure label)
<=> page 211, fig. 187.
2. Determine the combined
weight of the driver and pas ­
sengers that will be riding in
your vehicle .
3 . Subtract the combined weight
of the driver and passengers
from
"XXX" kilograms or "XXX"
pounds shown on the sticker
<=> page 211, fig . 187 .
4. The resulting figure equals the
available amount of cargo and
luggage load capacity . For ex ­
ample, if the "XXX" amount
equa ls 1400 lbs. and there will
be five 150 lbs. passengers in
your vehicle, the amount of available cargo and luggage load capacity is 650 lbs.
.,.
2 15

Care and cl eaning
- To reduce the risk of cuts, protect yourself
from sharp metal components when wash­ ing the underbody or the inside of the wheel
housings .
- After washing the vehicle, the braking effect
may be delayed due to mo isture on the
brake rotors or ice in the winter . This in­
c reases the risk of an acc ident. The brakes
must be d ried first w ith a few careful b rake
applica tions.
@ Note
- If you wash the veh icle in an automatic car
wash, you m ust fold the exte rior m irrors i n
to reduce the risk of damage to the mirrors.
Power folding exte rior m irro rs* must o nly
be fo lded in and out using the powe r folding
funct ion .
- To reduce t he risk of paint damage , do no t
wash the vehi cle i n direct sunlig ht. - T
o red uce the risk of damage to the s urface,
do not use insect removing sponges, kitchen
sponges o r similar items .
- Matte finish painted vehicle components:
- To reduce the r isk of damage to the sur-
face, do not use pol ish ing agents or hard
wax.
- Never use protective wax. It can destroy
the matte finish effect .
- Do not place any stickers or magnetic
signs on vehicle parts painted with matte
f inish paint. The paint could be damaged
when the stickers or magnets a re re­
moved.
@ For the sake of the environment
Only wash the veh icle in facilities spec ially de­
s igned for that pu rpose. This will reduce the
r isk of dirty wate r contam inated with o il from
en te ring the sewe r system.
Cleaning and care information
W hen clea ning and ca ring for ind ividua l vehicle
components, refer to the fo llow ing tables. The
information contained there is simply recom­
mendations. For questions or for components t
h at are not listed, cons ult an autho rized Audi
dealer or author ized A udi Servi ce Fac ility. Also
fo llow the information found
in ¢,&. .
Exterior cl eanin g
Component Situation Solution
Wind shield wiper
Deposits soft cloth with glass cleaner,
¢ page 45
blades
Headli ght s/
Deposits Soft sponge with a mild soap so lution3
)
Tail light s
S en sors /
Deposits Sensors: soft cloth with solvent-free cleaning solution
cam era l ens es Camera lenses: soft cloth w ith alcohol -free cleaning solu-
tion
Snow/ice Hand brush/solvent-free de -icing spray
Wheels Road salt Water
Brake dust Acid-free special cleaning solution
E
xhaust tail pip es Road salt Water, clean ing solution su itab le for stainless stee l, if nee-
essary
D ecor ativ e part s/ Deposits Mild soap solution a), a cleaning solution suitable for stain-
trim less steel, if necessary
222

Emergency assistance
Emergency assistance
General information
.,. Park the vehicle as far as possible from moving
traffic in the event of a breakdown. In the event
of a flat tire, park the vehicle on a level surface .
It you are on a steep hill, be especially careful.
.,. Set the parking brake .
.,. Switch the emergency flashers on .
.,. Set up the warning triangle r=;,page 226 .
.,. Have the passengers exit the vehicle . They
should move to a safe place, for example be­
hind a guard rail.
A WARNING
Follow the steps given above. This is for your
protection and the for the safety of other driv­
ers.
Equipment
Warning triangle
A pplies to: ve hicles w ith warning triangle
Fig. 190 Luggage compa rtment lid : wa rnin g triangle
The warning triangle placed in the vehicle at the
factory is located in the luggage compartment.
.,. To remove the warning triangle, press the re-
tainer in the direction of the arrow
r:;, fig . 190
and fold the holder down.
The luggage compartment lid is only designed to
hold the warning triangle offered by the Audi
Genuine Accessories program.
226
Vehicle tool kit
Fig. 191 Luggage compartment: vehicle tool kit
The vehicle tools and vehicle jack* are stored in
the luggage compartment under the floor cover.
.,. Lift the cargo floor by the plastic handle.
.,. Hook the handle into the luggage compartment
weather strip.
.,. Turn the handle counter-clockwise and remove
the cover or the spare tire* .
.,. Unhook the cargo floor before clos ing the lug­
gage compartment lid.
A WARNING
I mproper use of the veh icle jack can cause se­
rious personal injuries.
- Never use the screw driver hex head to
tighten wheel bolts, since the bolts cannot
attain the necessary tightening torque if yo u
use the hex head, potentially causing an ac­
cident.
- The factory-supplied jack is intended only
for your vehicle model. Under no circum­
stances should it be used to lift heavy
vehicles or other loads; you risk injuring
yourself.
- Never start the engine when the vehicle is
raised, which could cause an accident .
- Support the vehicle securely with appropri­ ate stands if work is to be performed under­
neath the vehicle; otherwise, there is a po­
tential risk for injury .
- Never use the jack supplied with your Audi
on another vehicle, particularly on a heavier
one. The jack is only suitable for use on the
vehicle it came with.