brakes AUDI A8 2020 User Guide

Driver assistance

Driver assistance
Cruise control system
Applies to: vehicles with cruise control system
The cruise control system assists the driver in
maintaining a constant speed above approxi-
mately 15 mph (20 km/h). The system maintains
the desired speed by braking and accelerating.

ZA WARNING
— Always pay attention to the traffic around
your vehicle when the cruise control system
is in operation. As the driver, you are always
responsible for controlling your vehicle
speed and the distance between your vehicle
and
other vehicles.
— For safety reasons, cruise control should not
be used in the city, in stop-and-go traffic, on
winding roads, and when road conditions are
poor (such as ice, fog, gravel, heavy rain,
and conditions that could lead to hydroplan-
ing), because this increases the risk of an ac-
cident.
— Switch the cruise control off temporarily
when driving in turning lanes, highway exits,
or in construction zones.
—To reduce the risk of an accident, you should
only resume the stored speed if it is suitable
for the current traffic conditions.


C) Note
— Conventional drive system: Before driving
downhill a long distance on a steep hill, de-
crease your speed and select a lower gear.
This makes use of the engine braking effect
and reduces the load placed on the brakes.
— Plug-in hybrid drive: Before driving downhill
a long distance on a steep hill, decrease
your speed and use the braking effect of re-
cuperation > page 118. This reduces the
load on the brakes.
@ Tips
The brake lights turn on when the brakes are
applied automatically.
166
Switching the system on
Applies to: vehicles with cruise control system

BFV-0220



Fig. 123 Lever: switching on the cruise control system
Requirement: The ignition must be switched on.
> To switch the system on, pull the lever toward
you to position @.
The Ga or 8) indicator light and the corre-
sponding message will appear in the instrument
cluster.

A WARNING
If the brakes are malfunctioning (for example,
overheating) while the cruise control system
is switched on, it may shut off automatically.
Preselecting or activating a cruise control
speed
Applies to: vehicles with cruise control system

When the vehicle is stationary, you can preselect
the cruise control speed or activate the speed
while driving.
Requirement: the system must be switched on.
> To preselect a cruise control speed when the ve-
hicle is stationary, tap the lever toward @)/C)
=> page 166, fig. 123.
> To activate the cruise control speed, pull the
lever
toward position @ while driving, or
> To set the current driving speed as the cruise
control speed, press the button @) on the lever.
The active cruise control speed is indicated with
the Gs or kl indicator light in the instrument
cluster.
An additional indicator appears in the head-up
display*.

4N0012721BD
Driver assistance

Changing the cruise control speed
Applies to: vehicles with cruise control system
> To increase or decrease the cruise control speed
in small increments, tap the lever up to the
first level toward @)/C) > page 166, fig. 123.
> To increase or decrease the cruise control speed
in larger increments, tap the lever up to the
second level toward ()/C).
> To increase or decrease the cruise control speed
continuously, tap and hold the lever at the first
or second level toward @)/G).
Overriding or deactivating the cruise
control speed
Applies to: vehicles with cruise control system
You can override or deactivate the cruise control
system. When you deactivate the system, your
cruise control speed will be stored and you can
resume that speed.
Requirement: the system must be switched on
and activated.
Overriding
> To temporarily override the cruise control
speed, press the accelerator pedal.
> Once you release the accelerator pedal, the sys-
tem will adjust back to the stored cruise control
speed.
If you override the cruise control system for a
long period of time, the cruise control system
will be deactivated. The ICRUISE| or 88) indicator
light will be displayed and the cruise control
speed will be saved.
Deactivating
> To deactivate the cruise control speed, press
the lever toward (2) (not locked into place)
=> page 166, fig. 123.
> Press the brake pedal.

ZA WARNING
Resting your foot on the accelerator pedal
could override the cruise control. This will pre-
vent braking interventions by the system.

Seem Leal
Applies to: vehicles with cruise control system
When you switch the system off completely, the
cruise control speed will be deleted.
Requirement: the system must be switched on.
> To switch the system off, press the lever toward
@ (locked into place) > page 166, fig. 123, or
> Switch the ignition off.
Applies to: vehicles with cruise control system
Gk / 3) Speed control system: currently un-
available. See owner's manual
If the indicator light turns on and this message
appears, the cruise control system has been deac-
tivated. There is a temporary malfunction, for ex-
ample the brakes are overheating. Switch the
cruise control system on again later.
Efficiency assist
Applies to: vehicles with efficiency assist
Efficiency assist can assist the driver with predic-
tive information in order to reduce fuel consump-
tion. Depending on vehicle equipment, the sys-
tem may access data from the navigation system,
the camera behind the windshield, and the radar
sensors.
When you remove your foot from the accelerator
pedal, efficiency assist controls downhill mode
with recuperation, depending on the situation.
Adjusting the efficiency assist
You can adjust efficiency assist functions individ-
ually. The settings depend on the vehicle equip-
ment.
— Predictive messages > page 168.
— Predictive control > page 169.
— Accelerator pedal feedback > page 115.
— Interactive accelerator > page 115.
167

Driver assistance

sensors > page 156, fig. 117 and try to turn on
the systems again later.
If the malfunction remains, drive to an author-
ized Audi dealer or authorized Audi Service Facili-
ty immediately to have the malfunction correct-
ed.

ZA\ WARNING
— Follow the safety precautions and note the
limits of the assist systems, sensors, and
cameras > page 154.
— Pay attention to traffic and the area around
your vehicle when predictive control is
switched on. The driver is always responsible
for assessing the traffic situation.
— The system does not consider “right of way”
rules and does not respond to traffic lights,
so lack of driver attention in these situations
can increase the risk of an accident.
— The speed when driving through curves may
be different from what you as a driver would
do or may not be suitable for the weather
and road conditions. If necessary, apply the
brakes and reduce the selected speed to be
maintained in the Adjustment to curves
along route setting to reduce the risk of an
accident.

G) Tips
— Predictive control can exceed or drop below
the maximum permitted speed. The driver
is responsible for adhering to the permitted
speed limit.
— The traffic signs on the road always take pri-
ority over the display. The driver is always
responsible for adhering to the regulations
applicable in the country where the vehicle
is being operated.
—If a speed limit is detected, the marking @
of the set speed limit will be adjusted even
if the adaptive cruise assist is not actively
regulating.
— Control by the system depends on which
adaptive cruise assist driving program is set
or on the selected Audi drive select* mode.

YD In certain countries
170
— After switching on the ignition and first
driving onto a freeway or similar road with-
out a speed limit, the system will regulate
the speed to 80 mph (130 km/h). Then
the system adjusts to the last speed set by
the driver.
— There is no adaptation to speed limits when
driving through highway interchanges and
when driving on or off the expressway.
— The system can fail to provide control or the
control may be faulty if the values from the
camera-based traffic sign recognition* are
incorrect or the navigation system map data
is outdated.
— When route guidance is switched on, the
system adapts to the route provided by the
navigation system. Driving without route
guidance or leaving a route can result in
faulty control.
— Certain settings are stored automatically in
the active personal profile.
Adaptive cruise assist
General information
Applies to: vehicles with adaptive cruise assist
Depending on the vehicle equipment, the adap-
tive cruise assist may consist of the following
functions:
Within the limits of the system, the adaptive
speed and distance control assists the driver in
controlling the speed and the set distance to the
vehicle driving ahead. If the system detects a ve-
hicle driving ahead, the adaptive cruise assist can
brake and accelerate your vehicle within the lim-
its of the system. On open roads with no traffic, it
functions like a cruise control system. The stored
speed is maintained. When approaching a vehicle
driving ahead, the adaptive cruise assist auto-
matically brakes to match that vehicle's speed
and then maintains the set distance as much as
possible. As soon as the system does not detect a
vehicle driving ahead, adaptive cruise assist ac-
celerates up to the set speed.

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Driver assistance

The additional lane guidance assists the driver
with corrective steering in order to stay in the
lane. You can adjust if the adaptive cruise assist
will provide support with lane guidance
= page 174, Switching lane guidance on and off.
In stop-and-go traffic and in traffic jams, the ve-
hicle may brake to a full stop and then may also
start driving again automatically under certain
conditions.
Applies to: vehicles with efficiency assist: Predic-
tive control can adjust the speed based on traffic
and road conditions > page 169, Predictive con-
trol.

Follow the safety precautions and note the
limits of the assist systems, sensors, and
cameras > page 154.


For an explanation on conformity with the
FCC regulations in the United States and the
Industry Canada regulations, see > page 339.
Applies to: vehicles with adaptive cruise assist

B8V-0630


Fig. 125 Example: vehicle changing lanes and stationary
vehicle



Fig. 126 Example: driving into a curve
In some situations, the adaptive cruise assist
function is limited and you must assume control
of the vehicle when necessary, for example by ap-
plying the brakes.
— Ifa vehicle that was already detected @ turns
or changes lanes, the adaptive cruise assist will
react to the vehicle ahead of it @).
— When driving into a curve > fig. 126 and out of
a curve, the adaptive cruise assist may react to
a vehicle in the adjacent lane and apply the
brakes. You can override the system by pressing
the accelerator pedal briefly.
— The adaptive cruise assist works with the vari-
ous sensors and cameras in the vehicle.
Vehicles can only be detected once they are
within the area and range covered by the sen-
sors > page 155, fig. 115.
— When driving around tight curves, a vehicle
driving ahead that was previously detected may
no longer be detected, and the adaptive cruise
assist may accelerate unexpectedly.
— The adaptive cruise assist does not react toa
stationary vehicle in the same lane if the sys-
tem expects that you can easily drive around
the stationary vehicle by turning the steering
wheel.
— The adaptive cruise assist may not react to sta-
tionary obstacles, such as the end of a traffic
jam, especially at high speeds.
— The adaptive cruise assist has a limited ability
to detect vehicles that are a short distance
ahead, off to the side of your vehicle, or moving
into your lane.
— Objects that are difficult to detect, such as mo-
torcycles, vehicles with high ground clearance,
or vehicles with an overhanging load, may be
detected late or not detected at all.
171

Driver assistance

— The adaptive cruise assist does not respond to
people, animals, or objects that are crossing or
approaching from the opposite direction.

Z\ WARNING
Follow the safety precautions and note the
limits of the assist systems, sensors, and
cameras > page 154.
Display overview
Applies to: vehicles with adaptive cruise assist

3] S|
me Ny Iz G3

Fig. 128 Instrument cluster: driver assistance display
Indicator lights and messages in the speedome-
ter @ -@) inform you about the driving situation
and the settings. In the Driver assistance display
@- ©, you can find more detailed information
about the system. The displays depend on the
country and equipment.
Display in the speedometer
The display in the speedometer is not available in
all layouts*.
@ Marking for the set speed
@ Current vehicle speed
@® Available speed range for adaptive cruise as-
sist (example)
172
Image in the Driver assistance display
The display only appears when the Driver assis-
tance display is open in the on-board computer
=> page 16.
Messages and settings
Detected vehicle driving ahead
Set target distance
If you fall below the set distance, the dis-
tance bars turn red from the bottom upward.
Your vehicle
©®
CO©®
Availability of lane departure warning
= page 180 and lane guidance
© Lane guidance for adaptive cruise assist is ac-
tive 1 or not active
Indicator lights
A - The speed/distance control is active. No
vehicles were detected ahead. The stored speed
is maintained.
Ba - The speed/distance control is active. A vehi-
cle was detected ahead. The adaptive cruise as-
sist controls the speed and distance from the ve-
hicle driving ahead, and accelerates and brakes
automatically.
A - The speed/distance control is active but the
vehicle is not ready to drive. A vehicle was de-
tected ahead. Your vehicle is stationary and will
not start driving automatically.
BS - The speed/distance control is active but the
vehicle is not ready to drive. No vehicles were de-
tected ahead. Your vehicle is stationary and will
not start driving automatically.
aA - The automatic braking is not enough to
maintain a sufficient distance to a vehicle driving
ahead. You must intervene > page 177, Driver in-
tervention request.
& This indicator light appears if steering activity
is no longer detected. Always keep your hands on
the steering wheel so you can be ready to steer at
any time. The indicator light will also turn off, for
example if the steering power from the system is
not sufficient and adaptive cruise assist is can-
celed > page 175.

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Driver assistance

— The driver's hands are not on the steering
wheel
Steering intervention request
If no steering activity is detected or the steering
power is not sufficient, the driver steering inter-
vention request will alert the driver using audio
and visual signals. Take over the steering and
keep your hands on the steering wheel so that
you will be ready to steer at any time. The system
will become inactive after a short time and will
only be active again later.
If the driver does not take over steering, adaptive
cruise assist will be canceled. If the vehicle is
equipped with emergency assist and it is ready to
function, it will be activated > page 190.

ZA WARNING
Follow the safety precautions and note the
limits of the assist systems, sensors, and
cameras > page 154.

@ Tips
— Always keep your hands on the steering
wheel. The driver is always responsible for
adhering to the regulations applicable in
the country where the vehicle is being oper-
ated.
— It is recommended to only switch on lane
guidance on well-constructed roads.
— Certain settings are stored automatically in
the active personal profile.
—The & fig. 131 button switches lane guid-
ance availability and the lane departure
warning on or off simultaneously, if lane
guidance is preset in the adaptive cruise as-
sist settings.
Setting the distance
Applies to: vehicles with adaptive cruise assist

B4M-0234



Fig. 132 Operating lever: setting the distance
If you adjust the speed, you must also change the
time gap to the vehicle driving ahead. The higher
the speed, the greater the distance that is need-
ed.
> Tap the rocker switch to display the distance
that is currently set.
> To increase or decrease the distance in incre-
ments, tap the switch again toward G) or ().
The newly-set distance will be shown briefly, for
example with the indicator light. In the Driv-
er assistance display, a graphic display is shown
instead of the indicator lights > page 172,
fig. 128. The display matches the functions of
the indicator lights.
When approaching a vehicle driving ahead, the
adaptive cruise assist brakes to the set speed and
then maintains the set distance. If the vehicle
driving ahead accelerates, then the adaptive
cruise assist will also accelerate up to the speed
that you have set.
The following distances can be set:
175

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Driver assistance

Audi pre sense basic
Applies to: vehicles with Audi pre sense basic
Audi pre sense basic is automatically active at
speeds of approximately 20 mph (30 km/h) and
higher. Audi pre sense basic can trigger the Audi
pre sense preemptive safety measures during
emergency braking and dangerous braking ma-
neuvers as well as in unstable driving situations,
such as oversteering or understeering.

Z\ WARNING
Follow the safety precautions and note the
limits of the assist systems, sensors, and
cameras > page 154.
Audi pre sense front
Applies to: vehicles with Audi pre sense front

The Audi pre sense front uses the data from the
camera and calculates the probability of a rear-
end collision. Within the limits of the system, an
impending frontal impact with vehicles, pedes-
trians), or cyclists!) may be detected in both ur-
ban and rural speed ranges.
Audi pre sense front is active at speeds of approx-
imately
6 mph (10 km/h) and higher. It can react
to pedestrians”) or cyclists!) at speeds up to ap-
proximately 50 mph (85 km/h), and can react to
vehicles at speeds up to approximately 155 mph
(250 km/h).
Early warning/acute warning
The system can recognize various dangerous sit-
uations. The early warning occurs if:
— A vehicle driving ahead brakes suddenly
— Your own vehicle approaches a vehicle in front
of you that is traveling at a significantly slower
speed or that is stationary
—A pedestrian or cyclist!) is standing in the lane
or is moving into the lane
The message Audi pre sense [J and a warning
tone will warn you about the danger.
The brakes may also be applied as an acute warn-
ing when there is an impending collision. You will

D_ This is not available in some countries.
also be warned by an indicator in the instrument
cluster display. When this warning occurs, it may
only be possible to avoid a collision by swerving
or braking strongly.
Automatic deceleration
If you do not react to the acute warning, Audi pre
sense front can brake the vehicle to a full stop
within the limits of the system )). This reduces
the vehicle speed in the event of a collision.
Automatic braking force increase
If Audi pre sense determines that you are not
braking strongly enough when a collision is immi-
nent, it can increase the braking force based on
the
situation.
Take-over
If the message Bo Please take over! appears, the
vehicle has been braked to a stop by Audi pre
sense and you must resume control of the vehi-
cle.

ZX WARNING
— Follow the safety precautions and note the
limits of the assist systems, sensors, and
cameras > page 154.
— Audi pre sense front cannot overcome natu-
ral physical laws. It is a system designed to
assist and it cannot prevent a collision in ev-
ery circumstance. The driver must always in-
tervene. The driver is always responsible for
braking at the correct time. Do not let the
increased safety provided tempt you into
taking risks. This could increase your risk of
a collision.
— Audi pre sense front does not react to cer-
tain objects, such as animals, crossing or on-
coming vehicles, bars, railings, or railcars.
— Audi pre sense front may be limited or un-
available when driving in curves.
— Loose objects can be thrown around the ve-
hicle interior during sudden driving or brak-
ing maneuvers, which increases the risk of
an accident. Store objects securely while
driving.

183

Driver assistance


as well as the vehicle's surroundings with di-
rect eye contact.
— The system may not react if vehicles are ap-
Proaching very fast.
@ Tips
For an explanation on conformity with the
FCC regulations in the United States and the
Industry Canada regulations, see > page 339.


Emergency assist
Applies to: vehicles with emergency assist
General information
Within the limits of the system, the emergency
assist detects if the driver is inactive. In these in-
stances, the system warns the driver, assumes
control of the vehicle if necessary, and brings the
vehicle automatically to a stop in the lane.
Regardless of the speed, the emergency assist is
automatically available when the adaptive cruise
assist* is activated. When the adaptive cruise as-
sist® is deactivated, the system is only active at
speeds higher than approximately 40 mph
(65 km/h).
Emergency assist functions
Within the limits of the system, the emergency
assist monitors the driver’s steering, accelerator,
and brake pedal activity. Depending on the se-
verity of the situation, it may initiate visual, au-
dio, and haptic warnings in stages:
— Reduces the speed
— Messages
— Lowers the volume of the Infotainment system
— Audible warning
— Tightening of the safety belt
—A brief application of the brakes

D_ This function is not available in every market and on all ve-
hicle equipment levels.
190
If the driver remains inactive despite the warn-
ings, the emergency assist controls the vehicle
within the limits of the system:
— The Audi pre sense preemptive safety measures
are triggered > page 182.
— The vehicle will stay in the lane and will be
braked to a stop.
— As soon as the vehicle comes to a full stop, the
emergency flashers are activated and the vehi-
cle prepares for the vehicle passengers to be
rescued. The parking brake is set, “P” gear is
engaged, the doors are unlocked, and the inte-
rior lighting is activated. If there is no move-
ment for several seconds, the emergency call ))
will be made if necessary.
Overriding the emergency assist
You can override the emergency assist > A\:
— Move the steering wheel. Or
— Press the brake pedal. Or
— Press the accelerator pedal distinctly.
When stationary, you can end the emergency as-
sist by leaving the "P" position or releasing the
parking brake > page 124.
Switching the emergency assist on and off
The system can be switched on and off in the
MMI ®& page 157.
Messages
1f E or EB is displayed when there is a malfunc-
tion, the emergency assist functions may be un-
available or may be limited.

A message that indicates the cause and possible
solution may appear with some displays. The
weather conditions may be too poor or a sensor
may be covered. Clean the area in front of the
sensors > page 156 and try to turn on the sys-
tems again later.
If the malfunction remains, drive to an author-
ized Audi dealer or authorized Audi Service Facili-
ty immediately to have the malfunction correct-
ed.

4N0012721BD
Checking and Filling

> 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.

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.


Z\ WARNING
— The engine compartment in any vehicle can
be a dangerous area. Stop the engine and al-
low it to cool before working in the engine
compartment. Always follow the informa-
tion found in > page 274, General informa-
tion.
— 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.
() 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
continue driving. See an authorized Audi deal-
er or authorized Audi Service Facility for assis-
tance.
Brake fluid

BFV-0229|




ZA WARNING
Applies to: vehicles with plug-in hybrid drive
— The coolant expansion tank for the high-
voltage 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-
der any circumstances > page 277, fig. 183.
If the coolant expansion tank for the high-


Fig. 186 Engine compartment: cap on brake fluid reservoir
Follow the safety precautions > page 274, Gener-
al 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. 183. The brake fluid lev-
el must be between the MIN and MAX markings
oA.
The brake fluid level is monitored automatically.
Message
GG / @ Brakes: stop vehicle and check brake
fluid level >
283

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.