2021 AUDI A4 ECU

Storage and convenience


— Applies to: vehicles with luggage compart-
ment cover: The luggage compartment cov-
er must always be securely fastened when in
use to reduce the risk of an accident.
— Loose objects can be thrown around the ve-
hicle interior during sudden driving or brak-
ing maneuvers, which increases the risk of
an accident. Always stow objects securely in
the luggage compartment and secure them
at the tie-downs. Use straps suitable for
heavy objects.
— If pieces of luggage or objects are secured
to the tie-downs with unsuitable or dam-
aged straps, this can increase the risk of in-
jury during braking maneuvers or accidents.
— When transporting heavy objects, the vehi-
cle characteristics will change due to the
shift in the center of gravity, which increases
the risk of an accident. You may need to
adapt your driving style and speed to the
current conditions.
— The cargo net* is only strong enough to se-
cure light objects. Heavy objects are not ade-
quately secured. Attempting to secure heavy
objects increases the risk of injury.
— Never exceed the permitted axle and load
and vehicle weight > page 287.
— Never secure a child safety seat to the tie-
downs.
— Never leave your vehicle unattended, espe-
cially if the luggage compartment lid is
open. Children could enter the luggage com-
partment and close the luggage compart-
ment lid from the inside. This creates the
risk of fatal injury, since the children would
be locked in and may not be able to escape
by themselves.
— Do not allow children to play in or on the ve-
hicle. Close and lock the luggage compart-
ment lid as well as all other doors when you
leave
the vehicle.
— Never transport passengers in the luggage
compartment. Every passenger must be cor-
rectly secured with the safety belts in the
vehicle > page 68.
— Be careful when releasing the backrest and
folding
it forward. To reduce the risk of be-


ing pinched, pay attention and check when
folding backrests forward.
— The backrest must be securely latched so
objects cannot slide forward out of the lug-
gage compartment during sudden braking.
— The backrest must be latched securely to en-
sure that the safety belt is protecting the
center seating position.
— Always pull forward on the backrest to make
sure it is check if it is correctly locked in
place.


84
() Note
—To reduce the risk of damage, move the rear
head restraints down > page 67 before fold-
ing the rear backrests forward.
— When folding the backrest forward, make
sure the outer safety belts are in the belt
guide recess so that they do not get pinched
in the backrest lock and damaged. Other ob-
jects should be removed from the rear
bench seat to protect the backrest from
damage.
— To reduce the risk of damaging the front
seats, make sure there is enough space be-
tween the front seat and the rear seat
equipment when folding the center backrest
forward.
— If you move the front seat back when the
rear seat backrest is folded forward, you
could damage the head restraints on the
rear seat.
— Make sure that the heating grid strips for
the rear window defogger are not damaged
by abrasive objects.
— Applies to: vehicles with manual luggage
compartment cover: Let the luggage com-
partment cover roll up slowly to reduce the
risk of damage.
— Applies to: vehicles with partition net: Let
the partition net roll up slowly to reduce the
risk of damage.
(i) Tips
— The tire pressure must be adapted to the
load > page 245.
— You can purchase straps at specialty stores.

8W1012721BC

Storage and convenience

Removing/installing the partition net
> To install the partition net, slide it into the left
and right mounts on the side trim panel.
> Press the partition net down diagonally at the
left and right until it locks into place and the
red markings on the buttons are no longer visi-
ble.
> To remove the partition net, press the left and
right buttons on the net and Lift it upward to re-
move it > fig. 82.
Partition net (backrests folded forward)
Applies to: vehicles with partition net

2 g
=
= a a


Fig. 83 Folded backrest: installing the partition net
B8W-0124
Fig. 84 Folded backrest: setting up the partition net
The partition net prevents objects from sliding
from the luggage compartment into the passen-
ger compartment.
Observe the safety precautions > page 83.
Removing/installing the partition net
> To install the partition net, fold the backrest
forward .> page 85
>» Place the partition net on the recesses in the re-
taining rails @ and slide it all the way to the
left @.
> To remove the partition net, first slide it to the
right and then lift it out of the retaining rails.
Setting up/storing the partition net
> To set up the partition net, pull it upward and
out and hook it into the mounting eyelets
above the front seats > fig. 84.
> To store the partition net, remove it from the
mounting eyes and let it roll up slowly.

You must remove the partition net before
folding the backrest back into the upright po-
sition.
downs and luggage compartme


: 1 dua da ha ees, WS
Fig. 86 Luggage compartment: luggage compartment net*
stretched out
Observe the safety precautions > page 83.
Tie-downs
There are tie-downs (d) in the luggage compart-
ment to secure pieces of luggage and objects.
> Use the tie-downs to secure the cargo.
Cargo net
Applies to: vehicles with cargo net
Use the cargo net (2) to secure lighter objects in
the luggage compartment
87

8W1012721BC
Storage and convenience


secure the roof rack system and objects on
the roof correctly, they could come loose
from the vehicle and cause an accident.
— The risk of an accident increases when using
a roof rack system, because it changes the
driving characteristics by shifting the center
of gravity and/or the increasing the surface
area exposed to wind. You may need to
adapt your driving style and speed to the
current conditions.

Make sure that the open luggage compart-
ment lid and the tilting/sliding sunroof* or
panoramic glass roof* do not come into con-
tact with objects on the roof.
Energy usage will increase because of the in-
creased wind resistance. Remove the roof rack
when you are no longer using it.
89

Warm and cold


Symbol | Meaning

Refer to the service information
(only available for authorized Audi
dealers or authorized Audi Service
Facilities)

The A/C system must only be serv-

e
Ri} iced by qualified technicians.
& Flammable refrigerant

Make sure all components are dis-
posed of correctly and never install
q components in the vehicle that have
been removed from old vehicles or
taken from recycling.

Lubricant in the A/C system
The sticker in the engine compartment provides
information about the type and amount of refrig-
erant oil used in the vehicle’s A/C system. For the
refrigerant oil quantity, refer to the Technical Da-
ta > page 287.

ZX WARNING
To ensure secure and safe operation, the A/C
system must only be serviced by qualified
technicians and certified technicians (SAE
standard J2845).

@ Tips
— Never repair the A/C system evaporator with
components from old vehicles or from recy-
cling.
— New replacement evaporators for portable
A/C systems must be certified and labeled
as such, so that they comply with the SAE
standard J2842 HFO-1234yf and R744.
94

8W1012721BC
Driving

Driving
Starting the vehicle
(eta
Applies to: vehicles with convenience key



Fig. 93 Center console: starting the engine
Requirement: the key must be in the vehicle.
Starting the engine
> Press and hold the brake pedal.
> Press the [START ENGINE STOP] button. The


engine will start.
Equipment that uses a lot of electricity is switch-
ed off temporarily when you start the engine. If
the engine does not start immediately, the start-
ing procedure stops automatically after a short
time. If this is the case, repeat the starting pro-
cedure after approximately 30 seconds.
Stopping the engine
> Bring the vehicle to a full stop.
> Press the [START ENGINE STOP] button. The


engine will switch off.
Applies to: vehicles with steering lock: The steer-
ing is locked when you turn off the engine and
open the driver's door. The steering lock helps
prevent vehicle theft. “P” must be engaged on
vehicles with an automatic transmission.
Stopping the engine in an emergency
If necessary in an emergency, the engine can also
be stopped while driving using the emergency off
function*.

> Press the [START ENGINE STOP] button twice in
a row or press and hold it one time.

Switching on and off
If you would like to switch the ignition on or off
without starting the engine, follow these steps:

> Press the [START ENGINE STOP] button without
pressing the brake pedal.

Switching the ignition off automatically
To prevent the vehicle battery from draining, the
ignition and possibly the exterior lighting may
switch off automatically.
Requirements:
— The Start/Stop system must have stopped the
engine.
— You must have left the vehicle for longer than
30 seconds.
— The ignition must be switched on.
Among other indicators, the system detects that
you have left the vehicle based on the following
factors:
— The driver's door has been opened.
— The driver's safety belt has been unbuckled.
— The brake pedal is not being pressed.
The ignition will also be switched off after 30 mi-
nutes or if you lock the vehicle from the outside.

Z\ WARNING
—To reduce the risk of asphyxiation, never al-
low the engine to run in confined spaces.
— Never turn off the engine before the vehicle
has come to a complete stop. Switching it
off before the vehicle has stopped may im-
pair the function of the brake booster and
power steering. You would then need to use
more force to steer and brake the vehicle.
The fact that you cannot steer and brake as
usual may increase the risk of accidents and
serious injuries.
— Secure the vehicle against rolling before ex-
iting the vehicle > page 96.

CG) Note
— Avoid high engine speed, full throttle, and
heavy engine load if the engine has not
reached operating temperature yet. You
could damage the engine.
95

Driving

— If the engine has been under heavy load for
an extended period of time, heat builds up
in the engine compartment after the engine
is switched off and there is a risk of damag-
ing the engine. For this reason, let the en-
gine run at idle for approximately two mi-
nutes before shutting it off.
G) Tips
— Brief noises are normal when starting and
stopping the vehicle and are no cause for
concern.
— For up to 10 minutes after stopping the en-
gine, the radiator fan may turn on again au-
tomatically or it may continue to run, even if
the ignition is switched off.
— It may not be possible to start the vehicle in
extremely low temperatures.
— Power will be fully available once the engine
is at operating temperature.
Messages
= Engine start system: malfunction! Please
contact Service
There is a malfunction in the engine start system.
Drive immediately to an authorized Audi dealer
or authorized Audi Service Facility to have the
malfunction repaired.
B Remote control key: key not detected. Is the
key
still in the vehicle?
The vehicle key was removed from the vehicle
while the engine is running. If the vehicle key is
no longer in the vehicle, you cannot switch the ig-
nition on or start the engine once you stop it. You
also cannot lock the vehicle from the outside.
Remote control key: hold back of key
against the designated area. See owner's man-
ual
The battery in the vehicle key may be drained or
there may be a malfunction. To start the vehicle,
you must also hold the vehicle key against the lo-
cation shown ?) > page 95, fig. 93.
If the malfunction remains, drive immediately to
an authorized Audi dealer or authorized Audi
96
Service Facility to have the malfunction correct-
ed.
When driving
Starting to drive, stopping, and parking
Starting from a stop
> Press and hold the brake pedal.
> Start the engine.
> Select a gear.
> Release the parking brake.
> Release the brake pedal. The vehicle may roll.
> Press the accelerator pedal to accelerate.
Securing the vehicle against rolling
Secure your vehicle to prevent it from rolling be-
fore exiting the vehicle.
> Set the parking brake.
> Select the “P” selector lever position.
> If parking on a steep road, turn the steering
wheel so that your vehicle will roll against the
curb in case it should start to move.
If one of these measures is not possible, for ex-
ample because there is no vehicle power, you
must secure your vehicle against rolling using ad-
ditional measures.
> Only park the vehicle on a level surface.
> Use suitable objects to block the front and rear
wheels.
Set the parking brake before selecting the “P” se-
lector lever position. This prevents too much
stress from being placed on the locking mecha-
nism when parking on a steep surface.

ZA WARNING
— Always set the parking brake when leaving
your vehicle, even if for a short period of
time. If the parking brake is not set, the ve-
hicle could roll away, increasing the risk of
an accident.
— Do not leave your vehicle unattended while
the engine is running, because this increases
the risk of an accident.
— If the parking brake is set, it can release au-
tomatically when the accelerator pedal is

pressed. To reduce the risk of an accident, >

Driving

“N” (Neutral) gear
In the “N” gear, power is not transmitted to the
driving wheels. Use the “N” gear in a car wash
(with conveyor belts), for example.
If you unintentionally select “N” while driving
(faster than 1 mph (2 km/h)), you can also shift
back to “D” without pressing the brake pedal.
For safety reasons, the vehicle cannot be locked
when the transmission is in the "N” gear.
“Pp” (Park) gear
Requirement: the ignition must be switched on.
The vehicle is secured from rolling away by the
parking lock when in the “P” gear.
— Bring the vehicle to a full stop and press the
brake pedal.
— Press the “P” button @) on the selector lever.
— The “P” next to the selector lever will light up.
“P” engages automatically if you switch the en-
gine off while the “D” or “R” gear is selected. If
you switch the engine off in “N”, “P” will engage
automatically after approximately 30 minutes.
If you want to switch from “P” to “D” or “R”, the
engine must be running.
If you cannot shift out of “P”, for example be-
cause the vehicle has no power, you may need to
use the emergency release for the parking lock
=> page 100.
Selecting a driving program
Various driving programs can be selected when in
the “D” gear. The programs influence when the
transmission shifts and how the accelerator ped-
al responds.
The selected driving program is displayed in the
instrument cluster.
—D (Drive): normal driving mode
— S (Sport): sporty driving mode
If you select the Dynamic mode in Audi drive se-
lect*, the “S” driving program will be activated.
When the ignition is switched off, the driving pro-
gram may be reset to “D”.
98
To switch between the current driving program
and “S”, push the selector lever toward the rear.

ZA WARNING
— Before you start driving, check if the label
for the desired selector lever position next
to the selector lever is lit up.
— Secure the vehicle against rolling before ex-
iting the vehicle > page 96.
— Power is still transmitted to the wheels
when the engine is running at idle. To pre-
vent the vehicle from “creeping”, you must
keep your foot on the brake in all selector
lever positions (except "P" and "N") when
the engine is running.
— To reduce the risk of an accident, do not
press the accelerator pedal when changing
gears if the vehicle is stationary and the en-
gine is running.
— Never select the “R" or "P” gears while driv-
ing. Doing so could cause an accident.
— The vehicle can roll even if the ignition is
switched off.

@) Tips
If you shift between “D” and “R” within one
second, you do not need to press the brake
pedal. This makes it possible to “rock” if it is
stuck, for example.

Driving

Manually releasing the parking lock
B8W-0047

B8W-0162



Fig. 98 Front cup holder: parking lock emergency release
The emergency release is located in the front cup
holder under a cover.
You will need the screwdriver and the socket
wrench from the vehicle tool kit in order to re-
lease > page 261. Use the flat side of the reversi-
ble screwdriver blade.
Releasing the parking lock using the
emergency release
> Secure the vehicle against rolling > page 96.
> Remove the rubber mat.
> Pry the cover off the opening using the screw-
driver inserted in the slot.
>» Insert the socket wrench from the vehicle tool
kit into the opening.
> Turn the socket wrench clockwise until it stops
@ and press it downward until it locks into
place Q).
> Leave the socket wrench inserted.
Resetting the parking lock
> Press the brake pedal and start the engine.
> Keep the brake pedal pressed and engage the
following selector lever positions one after the
other: "N","D", and back to ""N".
100
> Turn the engine off again.
> Grasp the socket wrench with both hands and
carefully pull it upward to remove.
> Reinsert the cover and rubber mat.

ZA WARNING
— Only use the parking lock emergency release
if the vehicle is secured against rolling
= page 96. An unsecured vehicle may roll,
which increases the risk of an accident.
— Only activate the emergency release while
on a level surface or a slight slope.
—To reduce the risk of an accident, you must
not drive when the emergency release is ac-
tivated.
C) Note
Due to the risk of damage, carefully remove
the socket wrench when you reset the parking
lock.
Messages
i Transmission: malfunction! Safely stop vehi-
cle


Do not continue driving. Stop the vehicle as soon
as possible in a safe location and secure it so it
does not roll > page 96. See an authorized Audi
dealer or authorized Audi Service Facility for as-
sistance.
& Transmission: too hot. Please stop vehicle
Do not continue driving. Select "P" and contact an
authorized Audi dealer or authorized Audi Service
Facility for assistance.
fal Transmission: too hot. Please adapt driving
style
The transmission temperature has increased sig-
nificantly. Drive very cautiously or take a break
from driving until the temperature returns to the
normal range and the indicator light turns off.
& Transmission: malfunction! You can contin-
ue driving. See owner's manual