2021 AUDI A4 ECU

8W1012721BC
Driving

There is a system malfunction in the transmis-
sion. You may continue driving. Drive to an au-
thorized Audi dealer or authorized Audi Service
Facility soon to have the malfunction corrected.
[@] Transmission: malfunction! You can contin-
ue driving with limited function. Please contact
Service
There is a system malfunction in the transmis-
sion. The transmission is switching to emergency
mode. This mode only shifts into certain gears or
may no longer shift at all. The engine may stall.
Drive to an authorized Audi dealer or authorized
Audi Service Facility immediately to have the
malfunction corrected.
[@] Transmission: malfunction! You can contin-
ue driving with limited function. No reverse
gear
There is a system malfunction in the transmis-
sion. The transmission is switching to emergency
mode. This mode only shifts into certain gears or
may no longer shift at all. The engine may stall.
You cannot engage the reverse gear. Drive to an
authorized Audi dealer or authorized Audi Service
Facility immediately to have the malfunction cor-
rected.
& Transmission: malfunction! You can contin-
ue driving in D until engine is off
There is a system malfunction in the transmis-
sion. The transmission is switching to emergency
mode. If you turn the engine off, you will not be
able to select any other gears after restarting the
engine. Drive to an authorized Audi dealer or au-
thorized Audi Service Facility immediately to have
the malfunction corrected.
fal Danger of rolling away! P not possible.
Please apply parking brake
— The parking lock was released using the emer-
gency release > page 100. Or
— The parking lock can no longer be engaged.
Drive to an authorized Audi dealer or author-
ized Audi Service Facility immediately to have
the malfunction corrected. Secure the vehicle
against rolling before exiting the vehicle
=> page 96.
fs} Selector lever: malfunction! Gear change on-
ly possible if using both shift paddles.
There is a system malfunction in the selector lev-
er. You can continue driving with restricted func-
tion. The selector lever is not working. Gears can
only be selected by tapping both shift paddles at
the same time when the vehicle is stationary. The
“P” gear is automatically engaged when you turn
off the engine. Drive to an authorized Audi dealer
or authorized Audi Service Facility immediately to
have the malfunction corrected.
fs] Selector lever: malfunction! You can contin-
ue driving. Please contact Service
There is a system malfunction in the selector lev-
er. Drive immediately to an authorized Audi deal-
er or authorized Audi Service Facility to have the
malfunction repaired.
fs} P button: malfunction! Auto P when engine
off. Please contact Service
There is a malfunction in the "P" button on the
selector lever. The “P” gear is automatically en-
gaged when you turn off the engine. Drive to an
authorized Audi dealer or authorized Audi Service
Facility immediately to have the malfunction cor-
rected.
Move selector lever to automatic position
There is a malfunction in the tiptronic mode. End
tiptronic mode by pushing the selector lever to
the left into the "D/S" position.
Drive system
A new vehicle must be broken in within the first
1,000 miles (1,500 km) so that all moving parts
work smoothly together, which helps to increase
the service life of the engine and other drive com-
ponents.
Do not drive higher than two-thirds of the maxi-
mum permitted engine RPM during the first 600
miles (1,000 km) and do not use full accelera-
tion. The engine can be increased RPM gradually
during the next 300 miles (500 km).
101

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


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.

8W1012721BC
Driving


ZA WARNING
Heavy braking while driving through curves or
in poor road or weather conditions can cause
the vehicle to slide or the rear of the vehicle to
swerve, which increases the risk of an acci-

dent.
Messages
ERG / GB) Parking brake: malfunction! Safely
stop vehicle. See owner's manual
Gg / @ Parking brake: malfunction! Please
release parking brake

If one of the two messages appears, there is a
malfunction in the parking brake. If the message
appears while stationary, check if the parking
brake is released and can be reset. If this is the
case, switch the ignition off and back on.
If the message stays on, if the parking brake can-
not be released, or if the message appears while
driving, do not continue driving. Secure the vehi-
cle against rolling before exiting the vehicle
=> page 96. See an authorized Audi dealer or au-
thorized Audi Service Facility for assistance.
ww Parking brake: malfunction! Please contact
Service
There is a malfunction in the parking brake. Drive
to an authorized Audi dealer or authorized Audi
Service Facility immediately to have the malfunc-
tion corrected. Do not park the vehicle on inclines
and secure it against rolling before exiting the ve-
hicle > page 96.
xt | / Parking brake: warning! Vehicle parked
too steep
The braking force may not be enough to secure
the vehicle from rolling away. Park the vehicle in
a place with less of an incline.
fa / Parking brake: applied
The parking brake is set. Press and hold the brake
pedal
to release the parking brake.
Take over!
The vehicle cannot be held in place automatically.
Press the brake pedal to secure the vehicle from
rolling away unintentionally.
Special driving situations
Driving uphill and downhill
When driving uphill, downhill, or at high alti-
tudes, note the following information:
— Drive slowly and carefully.
— Do not try to turn around if you cannot safely
drive on an incline or hill. Instead, drive in re-
verse.
— When driving down hills, you can activate the
hill descent control if you press the brake pedal
while driving in “D” gear. The automatic trans-
mission will select a gear suitable for driving
down the hill and will attempt to maintain the
speed at which the vehicle was traveling at the
time the brake pedal was pressed. Press the
brake pedal if necessary. The hill descent con-
trol will switch off once the hill levels out or
you press the accelerator pedal.
— Utilize the engine braking effect when driving
downhill by selecting the “S” driving program
=> page 98. This especially applies when towing
a trailer. This reduces the load on the brakes.
— Apply the brakes in intervals and do not press
the brake pedal continuously.
— Use the hill hold assist > page 108.

ZA WARNING
— Only drive on inclines that your vehicle is de-
signed to handle. Do not exceed the hill
climbing ability of your vehicle. Your vehicle
could tip or slide.
— Do not drive at an angle on steep inclines
and hills. If your vehicle is about to tip, you
must immediately start steering in the di-
rection of the downward slope to reduce the
risk of an accident.
— Always be ready to brake when using the hill
descent control function.

107

8W1012721BC
Driving dynamic

Suspension
CET tes un) Led
Applies to: vehicles with suspension control
The adaptive dampers are an electronically-con-
trolled damping system. The firmness of the sus-
pension will adapt to the driving conditions and
the driving situation. The settings depend on the
selected Audi drive select* mode.
Ground clearance
The vehicle height and clearance can be influ-
enced by the following factors:
— Change in temperature
— Change in load

Z\ WARNING
To reduce the risk of injury, make sure no one
gets pinched when the vehicle level is chang-
ing, for example when cleaning the under-
body or the wheel housings.
@) Note
Always make sure there is enough clearance
above and below the vehicle. This is especially
important for entrances with height restric-
tions, for example, before driving into under-
ground garages. You could also scrape the
ground when driving over the edges of curbs
or on steep ramps, which could damage your
vehicle.

Werle
8 | Suspension: malfunction! You can continue
driving
There is a malfunction. See an authorized Audi
dealer or authorized Audi Service Facility for as-
sistance.
Steering
Electromechanical steering supports the driver's
steering movements by electronically adapting
the power steering depending on the vehicle
speed. The settings depend on the selected Audi
drive select* mode.
Dynamic steering
Applies
to: vehicles with dynamic steering
The driving dynamic and driving stability are in-
creased by the steering ratio based on the speed.
At reduced speeds, steering is direct in order to
provide agile steering behavior and keep the
steering effort as minimal as possible when the
driver is maneuvering the vehicle. This sets the
steering to be less sensitive at higher speeds in
order to provide improved vehicle control.
a Steering: malfunction! Please stop vehicle
The power steering may have failed. Adapt your
driving style immediately to compensate for the
fact that it may be more difficult to turn the
steering wheel, and stop your vehicle in a safe lo-
cation as soon as possible. Secure the vehicle
against rolling before exiting the vehicle
=> page 96. Do not continue driving. See an au-
thorized Audi dealer or authorized Audi Service
Facility for assistance.
|e —e| Steering: malfunction! Please stop vehicle
There is a malfunction in the electronic steering
lock. You cannot turn the ignition on. Secure the
vehicle against rolling before exiting the vehicle
= page 96. Do not tow your vehicle because it
cannot be steered. See an authorized Audi dealer
or authorized Audi Service Facility for assistance.
a Steering: malfunction! You can continue
driving
There is a malfunction in the steering system.
Steering may be more difficult or more sensitive.
Adapt your driving style. Have the steering sys-
tem checked immediately by an authorized Audi
dealer or authorized Audi Service Facility. Please
note that the red indicator light may turn on af-
ter restarting the engine. Do not continue driving
if it does.
l@-| Steering lock: malfunction! Please contact
Service
111
>

8W1012721BC
Trailer towing

Trailer towing
Driving with a trailer
eT e e eeu)
Your vehicle is primarily intended for transport-
ing people and luggage. However, if you drive
with a trailer, follow the technical requirements,
the operation and driving tips, and the legal reg-
ulations.
Driving with a trailer affects the vehicle's energy
usage, performance, and wear. It also requires
higher concentration from the driver.

Z\ WARNING
Do not transport any people in a trailer due to
the risk of fatal injury.
Technical requirements
Trailer hitch

Only use a trailer hitch with a removable ball
hitch mount and ball hitch. The trailer hitch must
be permitted for the vehicle, the trailer and the
permitted total weight of the trailer being
pulled. Above all, it must be securely and safely
attached to the vehicle trailer.
Never mount a trailer hitch on the bumper. The
trailer hitch must be mounted in a way that does
not impair the function of the bumper. Do not
make any changes to the exhaust system and the
brake system.
Check regularly if the trailer hitch is securely
mounted. Always follow the instructions given by
the trailer hitch manufacturer.
Trailer brakes
If the trailer has its own brake system, then fol-
low the manufacturer specifications. However,
the brake system on the trailer must never be
connected to the vehicle brake system.
Engine cooling system
Driving with a trailer means a higher load on the
engine and the cooling system. The cooling sys-
tem must be designed for additional load and
contain enough coolant > @®.
CG) Note
Longer inclines cannot be driven without a
suitable cooling system, especially if the out-
side temperatures are high. Otherwise, this
increases the risk of engine damage.
Operating instructions
Towing capacity
Your vehicle can only be operated with class 1 or
class 2 trailers.
Load distribution
Poor cargo load and distribution can negatively
impact vehicle handling. Load the trailer based
on the following criteria as much as possible:
— Store objects in the vehicle luggage compart-
ment, if possible. The vehicle should always
carry the heaviest possible load and the trailer
should have the lightest possible load.
— Distribute the load in the trailer so that the
heavy objects are as close to the axle as possi-
ble.
— Secure objects so that they do not slide.
— Utilize the maximum permitted tongue weight
if possible.
Tires
Set the tire pressure on your vehicle for a “full
load”; see the tire pressure sticker > page 245. If
necessary, also adjust the tire pressure on the
trailer according to the manufacturer's specifica-
tions.
The trailer and the vehicle should be equipped
with winter tires when driving in winter tempera-
tures.
Outside mirrors
If you cannot see the traffic behind the trailer
with the standard exterior mirrors, then you
must attach additional exterior mirrors. Adjust
them so you have a sufficient visibility behind
you.
Exterior lighting
Follow the legal regulations for lighting on your
trailer that are applicable in the country where
115
>

8W1012721BC
Assist systems

Assist systems
General information
Sra eel delay

ZA\ WARNING
— As the driver, you are always completely re-
sponsible for all driving tasks. The assist
systems cannot replace the driver's atten-
tion. Give your full attention to driving the
vehicle, and be ready to intervene in the
traffic situation at all times.
— Activate the assist systems only if the sur-
rounding conditions permit it. Always adapt
your driving style to the current visual,
weather, road, and traffic conditions.
— 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.
— For the assist systems to be able to react
correctly, the function of the sensors and
cameras must not be restricted. Note the in-
formation on sensors and cameras
=>page 118.


@ Tips
— Pay attention to applicable local regulations
relating to driving tasks, leaving space for
emergency vehicles, vehicle distance, speed,
parking location, wheel placement, etc. The
driver is always responsible for following
the laws that are applicable in the location
where the vehicle is being operated.
— You can cancel a steering or braking inter-
vention by the system, by braking or accel-
erating noticeably, steering, or deactivating
the respective assist system.
— Always check the assist systems settings be-
fore driving. The settings could have been
changed, for example by other drivers.
System limitations
ZA\ WARNING
—The use of an assist system cannot over-
come the natural laws of physics. A collision
cannot be prevented in certain circumstan-
ces.
— Warnings, messages, or indicator lights may
not be displayed or initiated on time or cor-
rectly, for example, if vehicles are approach-
ing very fast.
— Corrective interventions by the assist sys-
tems, such as steering or braking interven-
tions, may not be sufficient or they may not
occur. Always be ready to intervene.
@) Tips
— Due to the system limitations when detect-
ing the surrounding area, the systems may
warn or intervene unexpectedly or too late
in certain situations. The assist systems may
also interpret a driving maneuver incorrectly
and then warn the driver unexpectedly.
— The systems may not function as expected
in unusual driving situations, such as driving
offroad, on unpaved roads, on loose ground,
on inclines, or on grooves in the road.
— The systems may not function correctly in
unclear traffic situations, such as turning
lanes, exit ramps, construction zones, rises
or dips that obstruct visibility, intersections,
toll stations, or city traffic.
— The detection of the surrounding area can
be limited, for example by vehicles driving
ahead or by rain, snow, heavy spray, or light
shining into the camera.
— The steering wheel touch recognition may
be limited when you wear gloves. Steering
intervention requests from the steering as-
sist systems may occur more frequently.
— If accessories have been mounted on the
steering wheel, the steering assist systems
may
be limited. The frequency of steering
intervention requests from the steering as-
sist systems may vary as well.


117