2021 AUDI A4 brake light

Driving

ient and environmentally-friendly

9g
Your driving style greatly influences the amount
of fuel and energy consumed, the environmental
impact, and the wear on the engine, brakes, and
tires. Note the following information for efficient
and environmentally-conscious driving:
— Turn off electrical equipment that is not need-
ed, for example seat heating*.
— Anticipate upcoming traffic situations while
driving to avoid unnecessary acceleration and
braking.
— Avoid driving at high speeds.
— Avoid adding extra weight to the vehicle if pos-
sible, for example by not leaving roof racks or
bike racks installed when they are not needed.
— Make sure the tire pressure is correct.
— Have maintenance performed regularly on the
vehicle.
— Do not let the engine run while the vehicle
parked.
— Do not drive with winter tires during the summ-
er.
— Use the Start/Stop system.
— Utilize the engine braking effect.
— Avoid driving short distances when possible.
@® Tips
The amount of noise produced by the vehicle
can increase significantly when driving with a
sporty style. Show respect to others around
you and the environment with the way you op-
erate your vehicle, especially at night.
ME ey
Your vehicle is equipped with an intelligent ener-
gy management system for distributing electrici-
ty. This significantly improves the starting ability
and increases the vehicle battery life.
@) Tips
— If you drive short distances frequently, the
vehicle battery may not charge enough
while driving. As a result, convenience func-
tions for electrical equipment may be tem-
porarily unavailable.
102
— The vehicle battery will gradually drain if
the vehicle is not driven for long periods of
time, or if electrical equipment is used
when the engine is not running. To ensure
that the vehicle can still be started, the
electrical equipment will be limited or
switched off.
I Cr Te (1
B Drive system: malfunction! Safely stop vehi-
cle
There is a malfunction in the drive system. The
brake
booster and the power steering may stop
working. Stop the vehicle immediately or as soon
as possible and do not continue driving. Secure
the vehicle against rolling before exiting the vehi-
cle > page 96. Have the problem corrected by an
authorized Audi dealer or authorized Audi Service
Facility.
B Drive system: malfunction! Please contact
Service
There is a malfunction in the drive system. Drive
slowly to an authorized Audi dealer or authorized
Audi Service Facility to have the malfunction cor-
rected.
Start/Stop system
Applies to: vehicles with Start/Stop system
The Start/Stop system can help increase fuel
economy and reduce CO2 emissions.
In Start/Stop mode, the engine shuts off auto-
matically when stopped, for example at a traffic
light. If certain conditions are met, the engine
may stop before the vehicle has come to a com-
plete stop. If you press the accelerator pedal
when this happens, the engine will start and driv-
ing power will be transmitted.
The ignition and important assist systems such
as the brake booster will remain available during
the Stop phase. The engine will restart automati-
cally when needed.
The Start/Stop system is automatically activated
once the ignition is switched on.

8W1012721BC
Driving

Switching the Start/Stop system off and on
The )* button is located above the selector lev-
er in the center console. The LED in the button
turns on when the function is switched off.
> Press (A)°* to switch the system on or off.
If you switch the system off during a Stop phase,
the engine will start again automatically.
Basic requirements
— The driver’s door and the hood must be closed
and the driver’s safety belt must be fastened.
—"P","N", or "D" must be engaged.
—The steering wheel must not be turned far in ei-
ther direction.
— The vehicle must have driven faster than 2 mph
(3 km/h) since the last time it stopped.
— The vehicle is not in trailer mode.
@ Note
Always switch the Start/Stop system off when
driving through water > page 103.
@ Tips
— Depending on the driving situation, the en-
gine may already stop when coasting before
the vehicle has come to a complete stop.
— If you select the "D" position after shifting
into reverse, the vehicle must be driven fast-
er than 6 mph (10 km/h) in order for the
Start/Stop system to become active again.
This makes it possible to maneuver without
stopping the engine.
Stopping and starting the engine
Applies to: vehicles with Start/Stop system
> Press and hold the brake pedal until the vehicle
has stopped. The @] indicator light appears in
the instrument cluster once the engine stops
automatically.
> The engine starts again when you remove your
foot from the brake pedal. The indicator light
turns off.
If the parking brake is set, the engine will only
start again when the accelerator pedal is pressed.
@) Tips
— Press the brake pedal during a Stop phase
to keep the vehicle from rolling.
— The ignition will turn off if you press the
START ENGINE STOP] button during a Stop


phase.
— If you leave the vehicle briefly during a Stop
phase and then enter again, the driver's
door must be closed and the safety belt
must be fastened in order for the engine to
be able to restart.
— You can control if the engine will stop or not
by reducing or increasing the amount of
force you use to press the brake pedal. For
example, if you only lightly press on the
brake pedal in stop-and-go traffic or when
turning, the engine will not switch off when
the vehicle is stationary. If you press the
brake pedal harder, the engine will switch
off.
Starting and stopping the engine automat-
ically
Applies to: vehicles with Start/Stop system
The system checks if certain conditions are met
before and during the Stop phase, and deter-
mines if the engine stops and how long it re-
mains stopped. For example, if power usage is
high, the engine will not be stopped. Along with
other conditions, the following factors influence
the automatic engine start or stop:
— Environmental conditions (slopes, inclines, ele-
vation, temperature)
— Battery (charge status, temperature, power us-
age)
— Engine temperature
— Assist systems
— Driving behavior
Depending on the engine, the Gy indicator light
may appear if the engine is not stopped.
Applies to: vehicles with Start/Stop system
Drive system: please start the vehicle manually >
103

Driving

This message appears when specific conditions
are not met during a Stop phase. The Start/Stop
system will not be able to restart the engine. The
engine must be started with the
START ENGINE STOP] button.


Vehicle starting system: malfunction! Please
contact Service
There is a malfunction in the Start/Stop system.
Drive the vehicle to an authorized Audi dealer or
authorized Service Facility as soon as possible to
have the malfunction corrected.
Brakes
General information
You can apply the vehicle's brakes using the brake
pedal.
Operating noise
Noises may occur when braking depending on the
speed, braking force, and outside conditions such
as temperature and humidity.
Braking effect
The response time from the brakes depends on
the weather and environmental conditions. To
ensure the optimal braking effect, the brake sys-
tem is cleaned at regular intervals. This is done
by applying the brake pads to the brake rotors for
a short period of time when driving at high
speeds when the windshield wipers are switched
on.
If the brake system becomes damp, for example
after driving in heavy rain, the braking effect may
be delayed. Other factors that could temporarily
increase the response time of the brakes include:
— Wet conditions
— Low temperatures, ice, and snow
— Roads covered in salt
— Dirty brake pads
Corrosion
Corrosion may form on the brake rotors if there is
no heavy braking, if the vehicle is not driven for
long periods of time, or if the vehicle is not driv-
en
frequently or for long distances. In this case,
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braking heavily several times while driving at
high speeds can clean the brake rotors > A\.
Brake pads
New brake pads do not achieve their full braking
effect during the first 250 miles (400 km). They
must be “broken in” first. However, you can com-
pensate for the slightly reduced braking force by
pressing firmly on the brake pedal. Avoid heavy
braking during the break-in period.
Brake pad wear depends largely on the way the
vehicle is driven and on operating conditions.
Brake pad wear increases when driving frequently
in the city or short distances or when using a very
sporty driving style.
Ceramic brakes
Applies to: vehicles with ceramic brakes
Ceramic brakes provide excellent deceleration
rates.
The break-in period for new ceramic brakes may
be significantly longer than for standard brake
rotors. Due to the properties of the material,
they may cause noises at lower speeds. Ceramic
brakes also absorb more moisture in wet condi-
tions. Therefore, there will temporarily be less
braking force than when the brakes are dry. You
can compensate for this by pressing the brake
pedal harder.
Automatic post-collision braking system
The automatic post-collision braking system can
help to reduce the risk of sliding and of addition-
al collisions after an accident. If the airbag con-
trol module detects a collision, the vehicle is
braked by the ESC.
The vehicle does not brake automatically if one of
the following occurs:
— The driver presses the accelerator pedal, or
— The braking force generated by the pressed
brake pedal is greater than the braking force
that would be initiated by the system
— The ESC, the brake system, or the vehicle elec-
trical system is not functioning

8W1012721BC
Driving


ZA WARNING
— Only apply the brakes for the purpose of
cleaning the brake system when road and
traffic conditions permit. You must not en-
danger other road users and increase the
risk of an accident.
— Due to the risk of injury, only have an au-
thorized Audi dealer or authorized Audi
Service Facility work on the brake system.
Incorrect repairs could impair the function.
— Never let the vehicle roll while the engine is
stopped because this increases the risk of an
accident.
— During automatic braking maneuvers, the
brake pedal may move downward automati-
cally. To reduce the risk of injury, do not
place your foot under the brake pedal.
@) Note
— Never let the brakes “rub” by pressing the
pedal lightly when braking is not actually
necessary. This can cause the brakes to over-
heat and increases braking distance and
causes wear.
— Observe the important information for driv-
ing downhill > page 107. This especially ap-
plies when towing a trailer.
@) Tips
— In vehicles with an electromechanical brake
booster, the resistance in the brake pedal
may vary depending on the driving situation
(such as if driver assistance system are ac-
tive).
— If you retrofit your vehicle with a front spoil-
er, wheel covers or similar items, make sure
that the air flow to the brakes is not ob-
structed. Otherwise the brake system can
overheat.

— Also refer to the information about brake
fluid > page 229.
Ga 7 @ Brakes: malfunction! Stop vehicle
safely
There is a malfunction in the brake system. If
[S/ Bana fA also turn on, there is a malfunc-
tion in the ABS, ESC, and braking distribution. If
the brake booster is not working, you have to use
much more force when braking the vehicle.
Do not continue driving. See an authorized Audi
dealer or authorized Audi Service Facility for as-
sistance. Read and follow the other safety pre-
cautions > A\.
Hie / © Brake pads: wear limit reached. You
can continue driving. Please contact Service
The brake pads are worn. Drive to an authorized
Audi dealer or authorized Audi Service Facility as
soon as possible to have the malfunction correct-
ed.
Brake booster: limited functionality. You can
continue driving. Please contact Service
There is a brake booster malfunction. The brake
booster is available, but its effectiveness is re-
duced. The braking performance may be different
compared to the usual performance. Drive to an
authorized Audi dealer or authorized Audi Service
Facility immediately to have the malfunction cor-
rected.
Brake booster: deactivated. See owner's manual
The brake booster remains active for a brief peri-
od of time after switching off the ignition. Secure
the vehicle against rolling > page 96.
Other indicator lights
When you switch the ignition on, the EG i @
indicator light turns on briefly to check the func-
tion. If the indicator light does not turn on, there
is a system malfunction.
file / © stays on, there is a malfunction in
the brake system.
@- A high load was placed on the brakes from
driving downhill for a long period of time. Follow
the instructions in the message to utilize the en-
gine braking effect and to relieve the brakes.

Z\ WARNING
If a malfunction occurs in the ABS, ESC, and
braking distribution, interventions that >

105

Driving


stabilize the vehicle will no longer be availa-
ble. This could cause the vehicle to swerve,
which increases the risk that the vehicle will
slide. Do not continue driving. See an author-
ized Audi dealer or authorized Audi Service Fa-
cility for assistance.

Electromechanical
parking brake
Operating the parking brake
The electromechanical parking brake is used to
secure the vehicle from rolling away unintention-
ally.
The ©) switch is located under the selector lever
in the center console. It turns on when the park-
ing brake is set. You can release the parking brake
manually or automatically when you start to
drive.
Setting and releasing the parking brake
> Setting: pull the ©) switch.
> 1f BM / © appears, the parking brake is hold-
ing the vehicle. You can remove your foot from
the brake pedal.
> Releasing: when the ignition is switched on,
press and hold the brake pedal and press the ©)
button.
If the red indicator light flashes, the braking
force has not built up enough or it has decreased.
You can also secure the vehicle by selecting the
“P” gear or pressing the brake pedal. Make sure
the indicator light is off before you start driving.
Automatically releasing the parking brake
when starting to drive
Requirement: the driver's door must be closed
and the driver’s safety belt must be fastened.
> Press the accelerator pedal to start to drive.

ZA\ WARNING
—To reduce the risk of an accident, always
make sure the vehicle is situated safely
while stationary.
— If the parking brake is set, it can release au-
tomatically when the accelerator pedal is

106
pressed. To reduce the risk of an accident,
do not inadvertently press the accelerator
pedal and always shift into “P” when the ve-
hicle is stopped.
— If the power supply fails, you cannot set the
parking brake once it is released, or release
it if it is set. Secure the vehicle against roll-
ing before exiting the vehicle > page 96. See
an authorized Audi dealer or authorized
Audi Service Facility for assistance.
G) Tips
— On steep inclines, especially when in trailer
mode, the vehicle may roll backwards unin-
tentionally when starting to drive. To reduce
the risk of this happening, pull and hold the
switch while pressing the accelerator
pedal. If enough drive power has built up at
the wheels and the vehicle does not roll
backwards, then release the switch to start
to drive.
— If you leave the vehicle when “D” or “R” are
engaged, the parking brake will be set auto-
matically.

— Noises when the parking brake is set and re-
leased are normal and are not a cause for
concern.
— The parking brake goes through a self-test
cycle at regular intervals when the vehicle is
stopped. Any noises associated with this are
normal.
Emergency braking function
Emergency braking should only be used in an
emergency, if the standard brake pedal is mal-
functioning or obstructed. When the emergency
braking function is activated, the braking effect is
similar to a heavy braking maneuver.
> Pull and hold the @) switch while driving.
» An audio warning signal will sound and emer-
gency braking will begin.
> If you press the accelerator pedal, emergency
braking will be canceled.

Driving

Offroad driving
Applies to: allroad
Your vehicle is not an offroad vehicle. Note the
following points when driving offroad:
— Drive slowly and carefully.
—To reduce the risk of underbody damage, pay
attention to the vehicle's ground clearance and
drive across raised areas of the ground with the
wheels on one side of the vehicle, instead of al-
lowing the center of the vehicle to pass over the
raised areas.
— To reduce the risk of becoming stuck, drive
through sandy or swampy areas at a steady
speed and without stopping, if possible.
If necessary, use the following functions:
— Audi drive select* Offroad mode > page 110
— Hill hold assist* > page 108
— Limit ESC > page 114

ZA WARNING
Only drive in terrain that is suitable for the ve-
hicle and your driving ability.

@ For the sake of the environment
Avoid actions that are damaging to the envi-
ronment. Show respect for the natural envi-
ronment and remain on marked routes.
G) Tips
Clean your vehicle after driving offroad. Dirt
and stones falling off your vehicle can affect
other road users.
Driving through water
If you must drive through water, follow these in-
structions:
— Check the stability of the ground, the current,
and the water depth. If the ground is unstable,
there is a strong current, or there are waves,
the water must only reach up to the lower edge
of the body at the most.
— Deactivate the Start/Stop system*.
— Drive carefully and no faster than at walking
speeds to prevent the front of the vehicle from
108
creating waves, because they could splash
above the lower edge of the body. Oncoming
vehicles could also create waves.
— Do not stop the vehicle while in the water.
— Drive in reverse.
— Do not turn the engine off.

ZA WARNING
After driving through water, press the brake
pedal carefully to dry the brakes so that the
full braking effect will be restored.
@) Note
Vehicle components such as the engine, drive
system, suspension, or electrical system can
be severely damaged by driving through wa-
ter
Gi) Tips
If possible, avoid driving through salt water
because it increases the risk of corrosion. Use
fresh water to clean any vehicle components
that come into contact with salt water.
Hill descent assist
Applies to: vehicles with hill hold assist


The “2 button is located above the selector lever
in the center console. It lights up when the sys-
tem is turned on.
Hill descent assist can assist you when driving
down hills by maintaining a constant vehicle
speed by automatically braking all four wheels.
You can adjust the speed using the accelerator
and brake pedals. The regulation depends on the
hill and the vehicle speed.
> Switching on: press “2.
> Switching off: press “2 again.
Active regulation
Regulation begins shortly after you start driving
and is possible at speeds up to approximately 19
mph (30 km/h) and on hills that have an approxi-
mately 6-60% grade. If these conditions are met,
regulation will be activated and the indicator
light will turn on.

8W1012721BC
Driving

Ready mode
If one of the requirements for active regulation is
not met, the system will be in ready mode. The
indicator light will turn on. Once the require-
ments are met again, the system will be able to
provide active regulation again.
— Be ready to apply the brakes at all times
when using the hill hold assist.
— Always adjust the speed to the visibility,
weather, road, and traffic conditions. The
system cannot replace the driver's atten-
tion.
— The system cannot maintain a constant vehi-
cle speed in all situations, for example when
on smooth or slippery ground. This can in-

crease the risk of an accident.

If you select the Audi drive select* Offroad
mode, hill descent assist will switch on.
109

8W1012721BC
Driving dynamic

The transmission temperature has increased sig-
nificantly due to the sporty driving manner. Drive
in a less sporty manner until the temperature re-
turns to the normal range and the indicator light
switches of.
it} Sport differential: temperature too high.
Please adapt driving style
The transmission temperature has increased sig-
nificantly due to the sporty driving manner. Drive
in a less sporty manner until the temperature re-
turns to the normal range and the indicator light
switches of.

Z\ WARNING
Contact an authorized Audi dealer or author-
ized Audi Service Facility if the sport differen-
tial is faulty or malfunctioning. The repair
must be performed by trained personnel us-
ing
the correct oil in order to ensure safety.

Electronic Stabilization
Control
Electronic Stabilization Control (ESC) supports
driver safety. It reduces the risk of slipping and
improves driving stability. ESC detects critical sit-
uations, such as if the vehicle is oversteering or
understeering, or if the wheels are spinning.
The brakes are applied or the engine torque is re-
duced in order to stabilize the vehicle.
The following stabilization functions are integrat-
ed into the ESC, among others:
Anti-lock Braking System (ABS)
ABS prevents the wheels from locking when brak-
ing. The vehicle can still be steered even during
hard braking. Apply steady pressure to the brake
pedal. Do not pump the pedal.
A pulsing in the brake pedal indicates that the
system is acting to stabilize the vehicle.
Anti-Slip Regulation (ASR)
ASR reduces drive power when the wheels begin
spinning and adapts the power to the road condi-
tions. This will increase the driving stability.
Electronic Differential Lock (EDL)
The EDL applies the brakes to wheels that are
slipping and transfers the drive power to the oth-
er wheels. This function is not available at higher
speeds.
In extreme cases, EDL automatically switches off
to keep the brake on the braked wheel from over-
heating. The vehicle is still functioning correctly.
EDL will switch on again automatically when con-
ditions have returned to normal.
Selective wheel torque control
Selective wheel torque control is used when driv-
ing on curves. Braking is targeted toward the
wheels on the inside of the curve as needed. This
allows more precise driving in curves.
Power steering
The ESC can also support vehicle stability
through steering.

ZA\ WARNING
—The ESC and its integrated systems cannot
overcome the limits imposed by natural
physical laws. This is especially important on
slippery or wet roads. If the systems begin
acting to stabilize your vehicle, you should
immediately alter your speed to match the
road and traffic conditions. Do not let the in-
creased safety provided tempt you into tak-
ing risks. This could increase your risk of a
collision.
— Please note the risk of a collision increases
when driving fast, especially through curves
and on slippery or wet roads, and when driv-
ing too close to objects ahead. There is still
a risk of accidents because the ESC and its
integrated systems cannot always prevent
collisions.
— Accelerate carefully when driving on
smooth, slippery surfaces such as ice and

snow. The drive wheels can spin even when

113