brake AUDI A3 SEDAN 2018 Workshop Manual

Checking and Filling
-Do not a pply u nder body protectant in t he
exhaust system area, because this increases
the risk of fire.
On Board Diagnostic
System (OBD)
The On-Board Diagnostic System monitors the
engine and transmission componen ts that influ ­
ence emissions.
F ig . 2 64 Footwell o n left s ide o f th e veh icle : co nn ect io n
port fo r the O n-Boa rd D iagno stic Syste m (OBD)
On-Board Diagnostic System
Engine data can be read out at the On-Board D i­
agnostic System connec tion po rt usi ng a special
tes ting device
~ fig . 264.
Indicator light
If thP ¢.j indicato r light bli nks or tu rns o n, there
is a malfunction that is causi ng poor emissions
qua lity and tha t could damage the ca talytic con­
ve rte r.
Drive s lowly to an author ized A udi dealer or au ­
thor ized Audi Se rvice Facility to have the ma l­
function co rrected .
The indicator light can also tur n on if t he fuel fill­
er cap is not closed
correct ly ~ page 315.
A WARNING
Incorrect use of the connection port fo r the
O n- Board Diag nostic System can ca use mal­
functions, which can then result in ac ciden ts
and ser ious injuries.
-Only allow a n author ized Audi dealer or au­
t h o riz e d Aud i Ser vice Faci lity to re ad o ut the
engi ne dat a.
318
-
Engine compartment
Working in the engine compartment
Special care is required if you are working in the
engine compartment
For work in the engine compartment, such as
checking and fill ing fluids, there is a risk of in­
jury, scalding, accidents , and burns . For thi s
reason, follow all the w arnings and general
safety p re caut ion s prov ided in the following in­
formation. The engine compartment is a dan­
gerous are a.
~ .&,.
A WARNING
To reduce the ris k of injur ies, comp lete the
follo wing steps before opening t he hood:
- Tur n t he engine off.
- Switch the igni tio n off.
- Set the park ing brake.
-Move the selector lever into the P position.
-N ever open the hood when there is steam o r
coo lant escaping from t he engine compart­
ment, because there is a risk that yo u could
be burned . Wait unt il no steam or coolant is
escapi ng.
- L et the eng ine cool down .
-Keep children away from the eng ine com-
pa rtment .
-Never sp ill fluids on a hot engine . These flu­
ids (such as the anti-freezing agent con­
tained i n the coolant) ca n ignite .
- Avoid short c ircuits in the electrical system .
-When working in the engine compa rtment,
remember that the radiator fan can switch
on even if the ignition is switched off, wh ich
increases the r isk of persona l injury .
-Never open the cap on the coolant expan­
sion tan k when t he engine is warm . The
coo ling system is under p ressure.
-To protect your face, hands , and a rms from
hot steam or coolant , cover the cap wit h a
large cloth when op ening .
-Do not remove the engine cover under any
circumstances. This increases the r isk of
burns .

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-If tests need to be performed with the en ­
gine running, there is additional danger due
to moving components (such as the ribbed belt, alternator and radiator fan) and from
the h igh-voltage ign it ion system .
- Never reach into the radiator fan. The elec­
tric auxiliary fan is controlled by tempera ­
ture and can switch on suddenly .
- Do not under any circumstances activate the
throttle inadvertently (for example, by hand
from the eng ine compartment) if the vehi­
cl e is stationa ry but the engi ne is ru nning
and a gear is engaged. Ot herw ise, the vehi­
cl e w ill sta rt to move immediately and t his
cou ld res ult in an accident .
- Pay atte ntion to the fo llow ing war nings list ­
ed when work on the fuel system or on the
electrical eq uipment is required.
- Do not smoke .
- Never work near open flames.
- Always have a working fire extinguisher
nearby.
- All work on the battery or e lectrica l system
in yo ur vehicle can res ult in injuries, chemi­
ca l burns, accidents or burns. Because of
this, all work must be performed
onl y by an
authorized Audi dealer or authorized Aud i
Service Facility .
- To reduce the risk of e lectric shock and in­
jury, never touch the following components when the eng ine is r unning or is being start­
ed:
- Ignition cable
- Other componen ts i n the ele ct ronic high-
voltage ignition system
- If you mus t check o r perfo rm wor k on t he
engine while it is runn ing:
- Set the parking brake and p lace the se lec­
tor lever in the P (park) position first .
- Always proceed with extreme caut ion so
that clothing, jewelry or long ha ir do not
become caught in the radiator fan, fan
belt o r other moving components or do
not come into contact with hot compo­
nents. Tie back lo ng ha ir before beginni ng
wo rk and do no t wear clot hing t hat can
hang down into the engine .
Check ing and F illing
- Limit your exposure to exhaust and chemi ­
cals to as short a time as possible
c> A .
A WARNING
-Ca lifornia Proposition 65 Warning:
- Engine exhaust, some of its constituents,
and certa in vehicle components conta in or
emit chemicals known to the State of Cali­
fornia to cause cancer and birth defects and reprod uctive harm . In add ition, certain flu­
ids conta ined in vehicles and certa in prod­
ucts of component wea r contain or em it
chemi cals know n to the State of Californ ia
t o cause cancer and b irth de fe cts or othe r
reprod uctive harm .
- Batte ry posts, te rm inals a nd rela ted a cces­
sor ies conta in lea d and le ad compo unds,
chemicals known to the State o f Cali fornia
to cause cancer and reproductive harms.
Was h hands after handling.
(LlJ) Note
When filling fluids, be su re not to m ix t he flu­
ids up . Otherwise severe malfunctions and en ­
gine damage will occur.
@ For the sake of the environment
You should regu lar ly check t he g ro u nd under
your vehicle in order to detect leaks quick ly . If
there are visib le spots from oi l o r other fluids,
bring your veh icle to an authorized A udi deal ­
er or authori zed Aud i Serv ice Facility to be
checked.
319

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Checking and Filling
Engine compartment overview
The most important check points .
Fig . 267 Typical location of the reservoi r, engine oil d ipst ick, and engine oil f iller open ing
(D Coolant expans ion tank (-L) ¢ page 325
@ E ngine oi l dipstick¢ page 322
® Engine oil filler opening ("e::r.) ¢ page 322
@ Eng ine oi l label* w ith VW standard
¢ page 321
® Brake fluid reservoir (0}) ¢ page 326
@ Applies to: vehicles w ith jump start point(+):
jump start point(+) under a cover
¢page 327, ¢page 375
0 Applies to: vehicles with the vehicle battery
in the engine compartment: vehicle bat­
tery(+) under the battery
cover¢ page 327,
¢page375
@ Bodygroundpoint(-) ¢page327,
¢ page375
® Washer fluid reservoir (0) ¢ page 328
@ Fuse housing ¢ page 3 71
The oil dipstick( @) and the engine oil fi ller
opening( @)¢ fig. 267 may be located in differ- ent places within the engine compartment de­
pending on the engine version .
,8. WARNING
Read and follow a ll WARNINGS before check­
i ng anything in the engine compartment
¢page 318 .
(D Tips
Applies to: vehicles with p lug-in hybrid dr ive:
note the informa tion for the coo lant expan­
s io n t ank
in¢ page 102 and for the vehicle
batte ry (+) in
¢page 102 .
Engine oil
If the engine oil level is too low
If you need to add engine oil, use an o il that i s
listed on the st icker .
The sticker is located at the
front of the eng ine
compartment ¢ page 321,
fig. 267.
321

Checking and Filling
Coolan t loss usu ally indicates there is a leak. Im ­
m ed iately drive your v ehicle to an authorized
Aud i dea ler or authorized Aud i Serv ice Facility
and have the cooling system inspected. If the
coo ling system is not leaking, a loss can come
from the coolant boiling through overheating
and be ing pushed out of the cool ing system.
.&_ WARNING
- The coo ling system is under pressure . Do
not open the coolant expans ion tank cap
when the eng ine is ho t. This inc reases the
risk of burns .
- T he coo lant add itive and the coolant can be
d angerous to your healt h. For this reason,
keep the coolant in the origina l container
and away from children . There is a risk of
poisoning .
- When working in the engine compartment,
remember that the rad iator fan can switch
on even if the ign ition is switched off, which
increases the risk of in jury .
-
CD Note
Do not add coolant if the expansion tank is
empty . Air could enter the cooling system and
damage the engine. If this is the case , do not
cont inue driving. See an authorized Audi deal­
er or author ized Audi Service Facility for assis­
tance .
Brake fluid
Fig. 271 Eng in e co mpar tment : cap on b rake flu id r eservo ir
O bserve the safety precautions ¢ page 318,
Working in the engine compartment .
326
Checking the brake fluid level
Read the b rake fluid level on the br ake fluid res­
ervoir ¢ page 321, fig . 267. The brake f lu id leve l
must be between the MIN and MAX markings
¢ ,& .
The brake f lu id leve l is monito red automa tically .
Changing the brake fluid
Have the brake fluid changed regularly by an au ­
thorized Aud i dea ler or authorized Audi Service
Facility.
.&_ WARNING
- I f the b rake fl uid leve l is below the MIN
marking, i t can impair the bra king effec t
and driving safety, wh ich increase the r isk o f
an accident. Do not continue driving . See an
authorized A udi dealer or authorized A udi
Serv ice Facility fo r ass istance.
- If the brake fl uid is old, b ubbles may form
in the brake system dur ing heavy braking.
This would impair braking performance and
driving safety, which increases the risk of an
accident .
- To ensure the brake system functions cor­
rectly, only use brake fluids that comp ly
w ith VW standard S0 l 14 or
FMVSS- 116 DOT 4 .
CD Note
-If the brake f luid level is above the MAX
marking, brake fluid may leak o ut over the
edge of the reservoi r and result in damage
to the vehicle .
- Do not ge t any brake fl uid on the vehicle
pai nt, b ecause it w ill co rrode the paint .
Battery
General warnings about batteries
Because of t he comp lex power supp ly, all work
on batter ies such as d isconnecting, replacing ,
etc., shou ld
only be pe rformed by an authori zed
Audi dealer or authorized A udi Service Fac ility
¢ _& . ~

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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 a re available as factory- in­
stalled equipment (whether i n­
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 s idewall 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 .
Wheel s
Cord
means the strands forming the
plies in the tire .
Cold tire inflation pressure
means the tire 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 with standard equipment in­
cluding the maximum capacity of
fuel, oil , and coolant, air condi­
tioning and additional weight of
optional eq uipm ent .
Extra load tire
means a tire designed to operate
at higher loads and at highe r in­
flation pressures than the corre­
sponding standard tire . Extra load
tires may be identified as "X L",
"xl", "EXTRA LOAD", or "RF" on
the sidewall.
.,.
333

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Production options weight
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 we ight, in­
c luding heavy duty brakes, ride
levelers, roof rack, heavy duty
battery, and special trim .
Radial ply tire
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.
Recommended inflation
pressure
see ¢ page 333, Cold tire infla­
tion pressure .
Reinforced tire
means a tire designed to operate
at higher loads and at h igher in ­
flat ion pressures than the corre­
sponding standard tire. Rein­
forced t ires may be identified as
"XL " "xl" "EXT RA LOA D" or "RF" , , ,
on the sidewall.
Wheels
Rim
means a metal support for a tire
or a tire and tube assembly upon
which the tire beads are seated .
Rim diameter
means nominal diameter of the
bead seat. If you change your
whee l 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 nominal distance between
rim flanges .
Sidewall
means that portion of a ti re 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 rat ings
range from
93 mph (150 km/h)
to
186 mph (298 km/h) ¢ table
on page 331.
You may no t find
this info rmat ion on all tires be­
cause it is not required by law.
T he speed rating letter code,
where applicable, is molded on
the tire sidewall and indicates t he
11>
335

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-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 al­ low enough air circulation to
cool the brake system. If they
do not, this could increase the risk of an accident.
Tire wear/damage
Fig. 276 T ire profile : treadwear indica­
tor
Tire wear
Check the tires regular ly for wear.
-Inflation pressure that is too low or high can increase tire wear
considerably.
-Driving quickly through curves,
rapid acceleration and heavy
braking increase tire wear.
l ) Obey any applicable regulations in your
country.
Wheels
-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 quickly.
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. 2 76. The letters "TWI"
or triangles on the tire sidewall indicate the location of the tread­
wear indicators.
The tires have reached the mini ­
mum tread depth
l) when they
have worn down to the treadwear
indicators. Replace the tires with
new ones
c::> .&.-
Tire rotation
Applies to: RS models: tires may
only be rotated if the tires on the
..,.
339

Wheels
vehicle's Gross Veh ic le Weig ht
R ati ng
("GVWR").
The "GVWR" includes the weight
of the basic vehicle, all factory in­
stalled accessories, a full tank of
fuel, oil, coolant and other fluids
plus maximum load. The maxi­
mum load includes the number of
passengers that the vehicle is in­
tended to carry ("seating capaci­
ty") with an assumed weight of 150 lbs . (68 kg) for each passen­
ger at a designated seating posi ­
tion and the total weight of any luggage in the vehicle. If you tow
a trailer, the weight of the trailer
hitch and the tongue weight of
the loaded trailer must be includ­
ed as part of the vehicle load .
The
Gro ss Ax le W eight Rating
("GAWR") is the maximum load
that can be applied at each of the
vehicle's two axles .
T he fact that there is an upper
limit to your vehicle's Gross Vehi­
cle Weight Rating means that the
total weight of whatever is being
carried in the vehicle (including
the weight of a trailer hitch and
the tongue weight of the loaded
trailer) is limited . The more pas­
sengers in the vehicle or passen -
344
gers who are heavier than the
standard weights assumed mean
that less weight can be carried as luggage .
The Gross Vehicle Weight Rating and the Gross Axle Weight Rat ing
are listed on the safety compli­
ance sticker labe l located on the
driver's side B-pillar.
1.8. 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 contro l and a crash.
-Always make sure that the to­ tal load being transported
-..

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Apply the product using a mic rofiber cloth. To
avoid damaging the paint surface, do not use too
much pressure .
R inse the veh icle t horo u ghly wi th wa ter. Then
clean using a neutra l shampoo and a soft micro ­
fiber cloth.
R inse the veh icle t horo u ghly again and let it a ir
d ry . Remove any water res idue using a ch amois.
A WARNING
-Only wash the vehicle when the ignition is
off and follow the instructions from the car
wash operator to reduce the risk of acci­ dents.
-T o reduce the risk of cuts, protect yourself
from sharp metal components when wash­ ing the underbody or the inside of the wheel
hous ings .
-After wash ing the vehicle, the brak ing effect
may be de layed due to mo isture on the
brake rotors or ice in the w inter . This in­
c reases the risk of an acc ident. The brakes
must be d ried fi rst w it h a few careful b rake
app lications.
@ Note
-If you wash t he veh icle in an automatic car
wash, you m ust fold the exterior m irrors in
-
Care and cleaning
to reduce the r isk o f damage to the m irro rs .
Power fo lding exterior mirrors* m ust only
be folded in and o ut using the power fold ing
function.
-T o red uce the risk of paint damage, do not
was h the vehicle in direct s unlight.
-T o red uce the risk of damage, do not was h
the power top * w ith a pressu re washe r.
-T o red uce the risk of damage to the s urface,
do not use insect removing sponges, kitche n
sponges or s imilar items.
-Matte finish painted vehicle components:
-To reduce t he risk of damage to t he sur-
face, do not use pol ish ing agents or hard
wax.
-Neve r use protective wax. It can destroy
the matte finish effect .
-Do not place any st ickers or magnetic
s igns on vehicle parts painted with matte
finish paint. The paint cou ld 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 ia lly de­
s igned for that pu rpose. This will reduce the
r isk of di rty wate r contam ina ted with o il from
en te ring the sewe r sys tem.
Cleaning and care information
When clea ning and caring for individua l vehicle
components, refer to the follow ing tables . The
in fo rmat ion conta ined there is s imp ly recom­
mendations . Fo r qu est io ns or for components t
h at are not listed, consult an authorized Aud i
dealer or authorized Audi Service Fac il ity. Also
fo llow the information found
in c:> ,& .
Exterior cleaning
Component Situation
Solution
Wind shield wip er
Deposits soft cloth wi th glass cleane r, ~ page 56
blade s
Headlights /
Deposits Soft sponge with a mild soap solutiona)
Tail light s
Sensors /
Deposits Sensors: soft cloth wit
h solvent -free cleaning solution
camera lenses Camera lenses: soft cloth with a lcohol-free cleaning so lu-
tion
Snow/ice Hand br ush/solven t-free de-icing spray
355

Care and cl eaning
Component Situation Solution
W hee ls
Road salt Water
Brake dust Acid-free special cleaning solution
Ex haust t ail p ipe s Road salt Water, cleaning solution suitab le for stainless steel, if nee-
essary
P ow er t op Deposits Clea n water, power top clean ing prod uct, if necessa ry.
C lean with the grain of the fabric using a soft brush and al -
l ow to air dry .
Wind deflect o r Deposits Water, mild soap solut ion, if necessaryal
Dec orat ive part s/ Deposits Mild soap so
lution al, a cleaning so lution suitable for stain-
trim less stee l, if necessary
Paint Paint damage Refer to the paint numbe r on the veh icle data label, repair
with touch up pa int¢
page 381
Spilled fuel Rinse with water immediately
S urface r ust Rust remover, then protect w ith hard wax; for questions,
consult an authorized Audi dealer or authorized Audi Serv -
ice Facility .
Corros ion Have it removed by an authorized Aud i dealer or author-
i zed Audi Service Fac ility.
Water no longer Protect with hard wax (at least twice per year)
beads on the surface
of clean paint
No sh ine even though Treat with s uitable polish; then apply paint protectant if
paint has been pro- the polish that was used does not contain any protectant
tected/paint looks poor
Deposits such as in- Dampen w ith wate r immediately and remove w it h a m icro-
sects, bird dropp ings, fiber cloth
tree sap and road salt
Grease-based con-Remove immediately with a mild soap solution al and a
tam inants such as soft cloth
cosmetics or sunblock
Ca rbon part s Deposits clean the
same way as painted parts ¢ page 354
Decorat ive decal s Deposits Soft sponge with a mild soap so lutional
a ) Mild soap so lution: maxim um two tablespoo ns of neut ra l soap i n 1 quart (1 liter) of water
Int erior cleaning
Component Situation Solution
Wind ows
Deposits Glass cleaner, then
wipe dry
Deco ra tive part s/ Deposits Mild soap solutional
trim
Pla stic part s
Deposits Damp cloth
Heavier deposits M ild soap so lution al, detergent-free p lastic clean ing solu-
tion, if necessa ry
356