brake AUDI A8 2021 Workshop Manual
[x] Cancel search | Manufacturer: AUDI, Model Year: 2021, Model line: A8, Model: AUDI A8 2021Pages: 362, PDF Size: 99.29 MB
Page 277 of 362
4N0012721BF
Checking and Filling
— Do not remove the engine cover under any
circumstances. This increases the risk of
burns.
— Due to the risk of electric shock, never touch
the ignition cable or other components in
the electronic high-voltage ignition system
when the engine is running or is starting.
— If a gear is engaged while the vehicle is sta-
tionary and the engine is running, do not
press the accelerator pedal inadvertently.
Pressing the accelerator pedal will cause the
vehicle to move, and this could result in an
accident.
— If inspections or repairs must be performed
while the engine is running, moving compo-
nents (such as the ribbed belt, generator,
and radiator fan) pose an additional risk.
— Set the parking brake first and select the
“P” (Park) selector lever position.
— Always make sure that no parts of the
body, jewelry, ties, loose clothing, and
long hair can be caught in moving engine
components. Before any work, always re-
move any jewelry and/or ties, tie back long
hair, and make sure all clothing fits close
to the body to reduce the risk of anything
becoming caught in engine components.
— 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.
— Limit your exposure to exhaust and chemi-
cals to as short a time as possible.
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.
ZA WARNING
California Proposition 65 Warning:
— Engine exhaust, some of its constituents,
and certain vehicle components contain or
@) Note
When filling fluids, be sure not to add any flu-
ids to the wrong reservoirs. Otherwise severe
malfunctions and engine 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.
275
Page 279 of 362
4N0012721BF
Checking and Filling
Engine compartment overview
The most important check points.
Fig. 181 Typical location of the reservoir and the engine oil filler opening (example)
Observe the safety precautions > page 274, Gen-
eral information.
@ Washer fluid reservoir (>) > page 287
@ Jump start point (+) under a cover, (-) with
hex head screw > page 286, Charging the 12
Volt vehicle battery > page 323, Jump start-
ing
Engine oil filler opening (7) > page 279
Brake fluid reservoir (OC) under a cover
=> page 283
Coolant expansion tank for combustion en-
gine (£) > page 282
© Plug-in hybrid drive: coolant expansion tank
for the high-voltage system (-) > page 282
©
©®&
@ Sticker* for engine oil specifications
=> page 277
The engine oil filler opening may be located ina
different area depending on the specific engine.
@ Tips
Plug-in hybrid drive*: read the information re-
garding the coolant expansion tank under
= page 282 and the jump start under >@ in
Preparation on page 324.
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 engine compartment > page 277,
fig. 181. When using the engine oil listed on the
sticker, you can adjust the oil level as often as
needed.
If engine oil that meets the recommended speci-
fication is not available, in an emergency you
may add a maximum of 1 quart (1 liter) of
ACEA C3 or API SN engine oil one time until the
next oil change.
277
>
Page 285 of 362
4N0012721BF
Checking and Filling
> Push the release button again and remove the
cap completely.
> Add coolant mixed in the correct ratio
=> page 281 up to the MAX marking.
> Make sure that the fluid level remains stable.
Add more coolant if necessary.
> Turn the cap to the right to tighten it until you
feel resistance a second time.
Coolant loss usually indicates that there is a leak.
Immediately drive your vehicle to an authorized
Audi dealer or authorized Audi Service Facility
and have the cooling system inspected. If the
cooling system is not leaking, coolant loss can re-
sult from the coolant boiling due overheating
and then being forced out of the cooling system.
der any circumstances > page 277, fig. 181.
If the coolant expansion tank for the high-
voltage system is not sealed, please contact
an authorized Audi dealer or authorized
Audi Service Facility.
— When adding coolant, it may leak into the
inside of high-voltage components and
cause a short circuit, increasing the risk of
fire.
ZA WARNING
— The engine compartment in any vehicle is a
potentially dangerous area. Stop the engine,
switch the ignition off, and allow the engine
to cool before working in the engine com-
partment. Always follow the information
found in > page 274, General information.
— Never open the hood if you can see or hear
steam or coolant escaping from the engine
compartment. This increases the risk of
burns. The cooling system is under pressure.
When you no longer see or hear steam or
coolant escaping, you may open the engine
compartment with caution.
— When working in the engine compartment,
remember that the radiator fan can switch
on even if the ignition is switched off, which
increases the risk of injury.
— Coolant additive and coolant can be danger-
ous to your health. For this reason, store the
coolant in the original container and away
from children. There is a risk of poisoning.
CG) Note
Do not continue driving if the coolant expan-
sion tank is empty. Do not add any coolant,
because air could enter the cooling system
and damage the engine. See an authorized
Audi dealer or authorized Audi Service Facility
for assistance.
Brake fluid
BFV-0229|
ZA WARNING
Applies to: vehicles with plug-in hybrid drive
The coolant expansion tank for the high-volt-
age system may only be opened or filled by an
authorized Audi dealer or authorized Audi
Service Facility.
— The coolant expansion tank cap is equipped
with a seal that must never be removed un-
Fig. 184 Engine compartment: cap on brake fluid reservoir
Observe the safety precautions > page 274, Gen-
eral information.
Checking the brake fluid level
> Slide the cover that is located below the wind-
shield wipers on the driver's side toward the
windshield and remove the cover.
> Read the brake fluid level on the brake fluid res-
ervoir > page 277, fig. 181. The brake fluid lev-
el must be between the MIN and MAX markings
oA.
The brake fluid level is monitored automatically.
Messages
EG 7 @ Brakes: stop vehicle and check brake
fluid level
283
>
Page 286 of 362
Checking and Filling
Stop the vehicle and check the brake fluid level.
See an authorized Audi dealer or authorized Audi
Service Facility for assistance.
Changing the brake fluid
Brake fluid should be changed at regular inter-
vals. Have the brake fluid changed by an author-
ized Audi dealer or authorized Audi Service Facili-
ty. The authorized Audi dealer or authorized Audi
Service Facility will inform you of the replace-
ment intervals.
ZA\ WARNING
— If the brake fluid level is below the MIN
marking, it can impair the braking effect and
driving safety, which increase the risk of an
accident. Do not continue driving. See an au-
thorized Audi dealer or authorized Audi
Service Facility for assistance.
— If the brake fluid is old, bubbles may form in
the brake system during heavy braking. This
could impair braking performance and driv-
ing safety, which increases the risk of an ac-
cident.
— The brake fluid in your vehicle must meet
the standard VW 501 14 and is available at
an authorized Audi dealer or authorized
Audi Service Facility. If this brake fluid is not
available, another high-grade brake fluid of
equivalent quality may be used, and it must
meet the U.S. Federal Motor Vehicle Stand-
ard (FMVSS) 116 DOT 4, Class 6.
@) Note
— If the brake fluid level is above the MAX
marking, brake fluid may leak out over the
edge of the reservoir and result in damage
to the vehicle.
— Do not allow any brake fluid to come into
contact with the vehicle paint, because it
will corrode the paint.
Electrical system
If the = / B or = indicator light turns on,
there is a malfunction in the power supply, the
battery, or the vehicle electrical system.
284
= / B Electrical system: malfunction! Safely
stop vehicle
Do not continue driving and switch the ignition
off > A\. See an authorized Audi dealer or author-
ized Audi Service Facility for assistance.
= Electrical system: malfunction! Restart not
possible. Please contact Service
If you switch the ignition off, you will not be able
to restart the vehicle. Vehicle functions or driving
stability may be limited. Drive to an authorized
Audi dealer or authorized Audi Service Facility im-
mediately.
=} Electrical system: malfunction! Please con-
tact Service
Switch off all electrical equipment that is not
needed. If necessary, some equipment will be
switched off automatically. Vehicle functions or
driving stability may be limited. Drive to an au-
thorized Audi dealer or authorized Audi Service
Facility immediately.
= Electrical system: low battery charge. Bat-
tery
will be charged while driving
The starting ability may be impaired.
If this message turns off after a little while, the
vehicle battery has charged enough while driving.
If this message does not turn off, drive immedi-
ately to an authorized Audi dealer or authorized
Audi Service Facility.
ZA\ WARNING
When there is an electrical system malfunc-
tion, vehicle functions may not work and driv-
ing stability may be limited, which increases
the risk of an accident. Do not continue driv-
ing and switch the ignition off. See an author-
ized Audi dealer or authorized Audi Service Fa-
cility for assistance.
Battery
Battery general information
Because of the complex power supply, all work on
batteries such as disconnecting, replacing, etc., >
Page 294 of 362
Wheels
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.
292
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 pres-
sure 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 equipment.
Extra load tire
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 “XL”,
“xl”, “EXTRA LOAD”, or “RF” on
the sidewall.
Page 296 of 362
Wheels
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 weight, in-
cluding 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 292, Cold tire infla-
tion pressure.
Reinforced 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.
294
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
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 nominal distance between
rim 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 290. 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 >
Page 300 of 362
Wheels
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 and damage
B4H-0415
a
Fig. 188 Tire profile: treadwear indica-
tor
Tire wear
Check the tires regularly 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.
—Have an authorized Audi dealer
or authorized Audi Service Facili-
D Obey any applicable regulations in the
country where the vehicle is being oper-
ated.
298
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 inch (1.6 mm) high and are
spaced evenly around the tire per-
pendicular to the running direc-
tion > fig. 188. 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 !) when they
have worn down to the treadwear
indicators. Replace the tires with
new ones > A.
Tire rotation
Rotating the tires regularly is rec-
ommended to ensure the tires
wear evenly. To rotate the tires, >
Page 305 of 362
4N0012721BF
Wheels
are listed on the safety compli-
ance sticker label located on the
driver’s side B-pillar.
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 in-
crease 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 sure that the to-
tal load being transported -
including 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 Weight Rating.
Determining correct load
limit
Use the example below to calcu-
late the total weight of the pas-
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. Locate the statement “THE
COMBINED WEIGHT OF OCCU-
PANTS AND CARGO SHOULD
NEVER EXCEED XXX KG OR XXX
LBS” on your vehicle’s placard
(tire inflation pressure label)
=> page 299, fig. 190.
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 299, fig. 190.
4. The resulting figure equals the
available amount of cargo and
luggage load capacity. For ex-
ample, if the “XXX” amount
equals 1400 lbs. and there will >
303
Page 313 of 362
4N0012721BF
Care and cleaning
height and width of the inside of the car
wash.
ZA WARNING
—To reduce the risk of accidents, only wash
the vehicle when the ignition is off and fol-
low the instructions from the car wash oper-
ator.
—To reduce the risk of paint damage, do not
wash the vehicle in direct sunlight.
—To reduce the risk of damage, do not wash
decorative decals* with a pressure washer.
—To reduce the risk of damage to the surface,
do not use insect removing sponges, kitchen
sponges, or similar items.
— When washing matte finish painted vehicle
components:
—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 moisture on the
brake rotors or ice in the winter. This in-
creases the risk of an accident. The brakes
must be dried with a few careful brake appli-
cations.
— To reduce the risk of damage to the sur-
face, do not use polishing agents or hard
wax.
— Never use protective wax. It can destroy
the matte finish effect.
@) Note — Do not place any stickers or magnetic
signs on vehicle components painted with
matte finish paint. The paint could be
damaged when the stickers or magnets
are removed.
— If you wash the vehicle in an automatic car
wash, you must fold the exterior mirrors in
to reduce the risk of damage to the mirrors.
Power folding exterior mirrors* must only
be folded in and out using the power folding (@) For the sake of the environment
function.
—To reduce the risk of damage to the rims
and tires, compare the width between the
wheels on your vehicle with the distance be-
tween the guide rails in the car wash.
—To reduce the risk of damage, compare the
height and width of your vehicle with the
Only wash the vehicle in facilities specially de-
signed for that purpose. This will reduce the
risk of dirty water contaminated with oil from
entering the sewer system.
Cleaning and care information
When cleaning and caring for individual vehicle are not listed, consult an authorized Audi dealer
components, refer to the following tables. The or authorized Audi Service Facility. Also follow
information contained there is simply recommen- __ the information found in > A.
dations. For questions or for components that
Exterior cleaning
Component Situation Solution
Windshield wiper | Deposits Soft cloth with glass cleaner, > page 67
blades
Headlights/ Deposits Soft sponge with a mild soap solution®
tail lights
Sensors/ Deposits Sensors: soft cloth with a solvent-free cleaning product
camera lenses Camera lenses: soft cloth with an alcohol-free cleaning sol-
ution
Snow/ice Hand brush/solvent-free de-icing spray >
311
Page 314 of 362
Care and cleaning
Component Situation Solution
Laser scanner Deposits Soft sponge with a mild soap solution®
Wheels Road salt Water
Brake dust Acid-free special cleaning solution
Exhaust tail Road salt Water, cleaning solution suitable for stainless steel, if nec-
pipes essary
Decorative parts | Deposits Mild soap solution ®, a cleaning solution suitable for stain-
and
trim
less steel, if necessary
Paint Paint damage Repair with touch-up paint
Spilled fuel Rinse with water immediately
Surface rust Rust remover, then treat with hard wax; for questions, con-
sult an authorized Audi dealer or authorized Audi Service
Facility.
Corrosion Have it removed by an authorized Audi dealer or authorized
Audi Service Facility.
Water no longer
beads on the surface
of clean paint
Treat with hard wax (at least twice per year)
No shine even though
paint has been pro-
tected/paint looks
poor
Treat with suitable polish; then apply paint protectant if
the polish that was used does not contain any protectant
Deposits such as in-
sects, bird droppings,
tree sap, and road
salt
Dampen with water immediately and remove with a micro-
fiber cloth
Grease-based con-
taminants such as
cosmetics or sunblock
Remove immediately with a mild soap solution ® and a soft
cloth
Carbon compo-__| Deposits clean the same way as painted parts > page 310
nents
Decorative decals | Deposits Soft sponge with a mild soap solution®
Audi e-tron Deposits Soft, dry towel
charging system
Wall mount clip | Deposits Soft towel with alcohol-free cleaning solution
a) Mild soap solution: maximum two tablespoons of
Interior cleaning
neutral soap in 1 quart (1 liter) of water
Component Situation Solution
Window glass Deposits Glass cleaner, then wipe dry
Decorative parts {Deposits Mild soap solution®
and
trim
312