engine AUDI S4 2021 Repair Manual

8W1012721BC
Wheels

Uc ede] )
Please note that the information
contained in the following table
was correct at the time of print-
ing, and the information is sub-
ject to change. If there are any
differences, you should always
follow the tire pressure sticker
=> page 245, fig. 167.
Make sure that the tire designa-
tion on your tire matches the des-
ignation on the tire pressure label
and the tire pressure table.
The following table lists recom-
mended tire pressures in cold
tires according to the load and
the size of the tires installed.



















Model/ Tire designation Tire pressure
Engine Normal load Maximum load
(up to 3 people)
Front Rear Front Rear
PSI | kPA | PSI | kPA | PSI | kPA | PSI | kPA
A4 sedan: 225/50 R17 94Y 30 | 210 | 28 | 190 | 33 | 230 | 33 | 230
2.0L 245/40 R18 93Y 30 | 210 | 28 | 190 | 33 | 230 | 33 | 230
ic sled 225/50 R17 94H 32 | 220 | 29 | 200 | 36 | 250| 36 | 250
245/40 R18 97H 35 | 240 | 32 | 220 | 36 | 250 | 36 | 250
245/35 R19 93Y 35 | 240 | 32 | 220 | 36 | 250 | 39 | 270
A4 sedan: 225/50 R17 94Y 30 | 210 | 28 | 190 | 33 | 230 | 33 | 230
2.0L 245/40 R18 93Y 30 | 210 | 28 | 190 | 33 | 230 | 33 | 230
ou 225/50 R17 94H 32 | 220 | 29 | 200 | 36 | 250| 36 | 250
245/40 R18 97H 35 | 240 | 32 | 220 | 36 | 250 | 36 | 250
245/35 R19 93Y 36 | 250 | 33 | 230 | 41 | 280 | 44 | 300
S4 sedan: 245/40 R18 97H 35 | 240 | 32 | 220 | 38 | 260 | 38 | 260
3.0 liter 245/40 R18 97Y 36 | 250 | 33 | 230 | 39 | 270 | 39 | 270
S-cylinder 255/35 R19 96Y 39 | 270 | 35 | 250 | 44 | 300| 45 | 310
A4allroad: |225/55R1797Y 32 | 220 | 29 | 200 | 33 | 230 | 30 | 210
2.0L 245/45 R18 96Y 32 | 220 | 29 | 200 | 35 | 240 | 32 | 220
4-cylinder — (345/45R18100H | 32 | 220 | 32 | 220 | 35 | 2401 35 | 240
245/40 R19 98Y 35 | 240 | 32 | 220 | 38 | 260 | 35 | 240
a) Two people in the front, one person in the rear
A WARNING pressure > page 245 and load
Please note the important safe- limits > page 248.
ty precautions regarding tire


247

8W1012721BC
Emergency assistance

bracket on the jack @) completely covers the
notch on the vehicle.
> Align the vehicle jack so the bracket (@) covers
the notch and the base (2) is flat on the ground.
The base @) must be directly under the mount-
ing point @.
> Mount the crank on the vehicle jack: insert the
crank into the opening on the handwheel. Turn
the crank to the left or right to secure it.
> Continue raising the vehicle jack with the crank
until the wheel lifts off the ground slightly.


ZA WARNING
—To reduce the risk of injury, make sure no
one is in the vehicle before raising it.
— Make sure the vehicle jack is stable. The risk
of injury is increased when the ground is
slippery or soft, because the vehicle jack
could slide or sink.
— Only raise your vehicle with the vehicle jack
provided by the factory. If you use a vehicle
jack designed for another vehicle, your vehi-
cle could slip and cause injury.
— Position the vehicle jack only at the desig-
nated mounting points on the side sill and
align the jack. Otherwise, the vehicle jack
could slip and cause an injury if it does not
have sufficient hold on the vehicle.
—To reduce the risk of injury, do not raise any
other vehicles or other loads using the vehi-
cle jack provided by the factory.
— To reduce the risk of an accident, never start
the
engine when the vehicle is raised.
—To reduce the risk of injury, no work should
be performed under the vehicle while it is
raised.

() Note
Do not lift the vehicle by the sill. Position the
vehicle jack only at the designated mounting
points on the side sill. Otherwise, your vehicle
could be damaged.
Removing and installing a wheel
| B8K-1479

Fig. 178 Wheel: alignment pin in the top hole
Removing a wheel
> Remove the top wheel bolt completely using
the hex socket in the screwdriver handle from
the vehicle tool kit > fig. 177 and place it ona
clean surface.
> Then install the alignment pin from the vehicle
tool kit in the empty wheel bolt hole by hand
> fig. 178.
> Remove the rest of the wheel bolts.
>» Remove the wheel >(). The alignment pin re-
mains in the hole while doing this.
Installing a wheel
Read the directions on > page 266 when instal-
ling unidirectional tires.
> Slide the wheel on over the alignment pin >@.
> Install the wheel bolts and tighten them gently
using the hex socket.
> Remove the alignment pin and tighten the re-
maining wheel bolt.
> Carefully lower the vehicle using the vehicle
jack*.
> Tighten the wheel bolts in a diagonal pattern
using the wheel wrench*.
265

Emergency assistance

@) Note
The compressor must be switched off after six
minutes at the most to reduce the risk of
overheating. Let the compressor cool down
for several minutes before using it again.
Jump starting
You should only perform the steps that follow if
you have the necessary tools and technical ex-
pertise.
If the engine does not start because the vehicle
battery is drained, you can jump start your vehi-
cle using another vehicle. Jump start cables are
needed to do this.
Both vehicle batteries must have 12 V nominal
voltage. The voltage capacity (Ah) of the vehicle
battery that is giving power must not be less
than the capacity of the drained vehicle battery.
Jump start cable
Only use a jump start cable with a large enough
diameter. Note the manufacturer's specifica-
tions.
Only use a jump start cable with insulated termi-
nal clamps.
Positive cable - usually red.
Negative cable - usually black.

ZA\ WARNING
— A drained battery can freeze at tempera-
tures around 32 °F (0 °C). If the vehicle bat-
tery is frozen, it must be thawed before con-
necting the jump start cables. If it is not,
the risk of an explosion and chemical burns
increases. After jump starting the vehicle,
drive to an authorized Audi dealer or author-
ized Audi Service Facility immediately to
have the vehicle battery checked.
— Read the warnings when working in the en-
gine compartment > page 221.
— Handling the jump start cables incorrectly
may cause the vehicle battery to explode
and lead to serious injuries.

268
@) Note
Jump start cables can cause considerable
damage to the vehicle electrical system if
they are connected incorrectly.
@) Tips
— There must be no contact between the
vehicles, or else voltage could flow when
connecting the positive terminal and drain
the vehicle battery of the vehicle providing
the jump start.
— The drained vehicle battery must be con-
nected correctly to the electrical system.
— Switch off electrical equipment that is not
needed.

Both jump start cables must be connected in the
correct order.

Fig. 179 Engine compartment: connectors for jump start
cables or a charger



Fig. 180 Engine compartment: connectors for jump start
cables or a charger
The jump start cable connections are located in
the engine compartment.
Follow the information about the vehicle battery
=> page 230. >

8W1012721BC
Emergency assistance

Connecting the positive cable (red) to the
positive terminal
> Open the cover on the positive terminal
> fig. 179.
1. Attach one end of the positive cable (red) to
the jump-start pin @ © fig. 180 on your vehi-
cle.
2. Attach the other end of the positive cable
(red) to the positive terminal @ on the pow-
er source.
Connecting the negative cable (black) to the
negative terminal
3. Attach one end of the negative cable (black)
to the negative terminal @) on the power
source.
4. Attach the other end of the negative cable
(black) to the jump-start pin @) on the vehi-
cle.
Starting the engine
>» Start the engine in the vehicle giving the charge
and let it run at idle.
> Now start the engine in your vehicle, which has
the
drained battery.
> If the engine does not start, stop the starting
procedure after 10 seconds and then repeat it
after approximately 30 seconds.
> Turn on the rear window defogger in your vehi-
cle in order to reduce any voltage peaks that
may occur when disconnecting the jump start
cables. The headlights must be switched off.
> With the engines running, remove the cables in
reverse order of the way they were installed.
> Close the cover on the positive terminal.

ZA WARNING
— Never connect the jump start cable directly
to your vehicle battery. Only use the connec-
tions in the engine compartment.
— Do not touch the non-insulated parts of the
terminal clamps. The cable must also not
come into contact with vehicle components
that conduct electricity when it is connected
to the positive vehicle battery terminal. This
can cause a short circuit.
— The plugs on the battery cells must not be
opened.

— Keep ignition sources (such as open flames,
burning cigarettes, etc.) away from the vehi-
cle batteries to reduce the risk of an explo-
sion.
— Route the jump start cables so they cannot
get caught in the moving parts in the other


vehicle's engine compartment.
() Note
Please note that the connecting process previ-
ously described for the jump start cables is in-
tended for when your vehicle is being jump
started.
G) Tips
Make sure that the connected jump start ca-
bles have sufficient contact with metal.

Towing
General information
You should only perform the steps that follow if
you have the necessary tools and technical ex-
pertise.
Towing requires a certain amount of practice.
Audi recommends contacting a towing company
to have the vehicle transported.
You should only have your vehicle towed by an-
other vehicle when disabled in exceptional cir-
cumstances. Inexperienced drivers should not
tow.
Notes on towing
When the engine is stopped, the transmission
will not be sufficiently lubricated if traveling at
high speeds and long distances:
— The maximum permitted towing speed is 30
mph (50 km/h).
— The maximum permitted towing distance is 30
miles (50 km).
Additional information on towing with a tow
truck
The vehicle may only be towed with the front axle
raised. Do not wrap any chains or cables around
the brake lines.
269
>

8W1012721BC
Fuses and bulbs

@) Note
If a new fuse burns out again shortly after you
have installed it, have the electrical system
checked as soon as possible by an authorized
Audi dealer or authorized Audi Service Facili-
t y.
G@) Tips
— The following table does not list fuse loca-
tions that are not used.
— Some of the equipment listed in the follow-
ing tables applies only to certain model ver-
sions or certain optional equipment.

Fig. 184 Driver's footwell (left-hand drive vehicle): fuse
panel with plastic clip
3
=f
= & a

x
Ss $ 2 8

Fig. 185 Front passenger's footwell (right-hand drive vehi-
cle): fuse panel with plastic clip


f ) (brown)
No. | Equipment

1 | Catalytic converter heating

2 | Engine components

Exhaust doors, fuel injectors, radiator in-
let, crankcase housing heating

Vacuum pump, hot water pump, NOx sen-
4 |sor, particulate sensor, biodiesel sensor,
exhaust doors

Brake light sensor

6 | Engine valves, camshaft adjustment

Heated oxygen sensors, mass airflow sen-
sor, water pump

Water pump, high pressure pump, high
8 |pressure regulator valve, temperature
valve, engine mount

Hot water pump, motor relay, 48 V drive-
train generator, 48 V water pump

10 | Oil pressure sensor, oil temperature sensor

Clutch position sensor, 48 V drivetrain
11 |generator, water pump, 12 V drivetrain
generator

12 | Engine valves, engine mount


13 | Engine cooling

273

Fuses and bulbs






Fuse panel @) (brown) Fuse panel (© (black)
14 | Fuel injectors, engine control module 11 Left rear door control module, left rear
15 |Ignition coils, heated oxygen sensors power window
16 | Fuel pump 12 | Parking heater
Fuse panel (®) (red) Fuse panel (0) (black)
No. | Equipment No. | Equipment

Anti-theft alarm system

Front seat electronic, seat ventilation,
rearview mirror, rear climate control sys-

































tem control panel, windshield heating, di-
agnostic connection
2 Diagnostic interface, vehicle electrical sys-
tem control module
3 |Sound generator
4 |Clutch position sensor
5S |Engine start, emergency shut-off
6 Diagnostic connection, traffic information
antenna (TMC)
7 |USB input
8 |Garage door opener
9 Audi adaptive cruise control, distance reg-
ulation
11 | Front camera
12 | Right headlight
13 | Left headlight
14 | Transmission fluid cooling
Fuse panel (©) (red)
No. | Equipment
1 {Ignition coils
2 |Climate control system compressor
S |Left headlight
6 |Automatic transmission
7 |Instrument panel
8 | Climate control system blower
9 |Right headlight
10 | Dynamic steering
11 | Engine start



2 | Engine control module
3 Left front seat electronics, lumbar sup-
port, massaging seat
4 | Automatic transmission selector lever
5 |Horn
6 |Parking brake
7 | Diagnostic interface
8 | Roof electronics control module
9 |Emergency call module
10 | Airbag control module
11 Electronic Stabilization Control (ESC), An-
ti-Lock Braking System (ABS)
12 | Diagnostic connection, light/rain sensor
13 | Climate control system
14 | Right front door control module
15 | Climate control system compressor
16 | Brake system pressure reservoir
Fuse panel (©) (black)
No. | Equipment
Front seat heating
2 |Windshield wipers
Left headlight electronics
4 Panoramic glass roof / sliding/tilting sun-
roof
5 |Left front door control module
6 | Sockets
7 Right rear door control module, right rear
power window
All wheel drive control module
9 | Right headlight electronics
10 Windshield washer system/headlight

washer system control module

274

Fuses and bulbs


2 | Audi phone box

Right front seat electronics, lumbar sup-
port, massaging seat
4 |Side assist


6 |Tire pressure monitoring system

Convenience access and start authoriza-
tion control module

8 | Auxiliary heating, tank module

TV tuner, data exchange and telematics
10 control module

11 | Auxiliary battery control module

12 | Garage door opener

13 | Rearview camera, peripheral cameras
14 | Right tail lights
16 | Airbag control module



No. | Equipment

Exhaust treatment
Right trailer hitch light
Trailer hitch
Left trailer hitch light
Trailer hitch socket


WO)
O};N]/
Mm|
Ww

All wheel drive control module, sport dif-
10
ferential


11 | Exhaust treatment

Bulbs
Replacing bulbs
Audi recommends having a bulb replaced by an
authorized Audi dealer or authorized Audi Service
Facility in cases of doubt. These facilities have
the correct tools and replacement parts as well
as the required technical knowledge.
LED lights*
Your vehicle is equipped with maintenance-free
headlights and tail lights. However, if a light bulb
needs to be replaced, please contact an author-
ized Audi dealer or authorized Audi Service Facili-
ty.
276

If you still would like to try replacing the
bulbs in your vehicle yourself, read the warn-
ings regarding working in the engine compart-
ment > A\ in General information on
page 221.

Make sure the covers are fitted correctly on
the headlight and tail light so that no water
will leak in from the outside and the light
function will not be impaired.

8W1012721BC
Data privacy

Data privacy
Privacy
notice
You can find information about responsibility for
data protection in the MMI.
Applies to: MMI: Select on the home screen: SET-
TINGS > General > Legal notes > About Audi
connect.
Image recording
Surrounding area monitoring
Applies to: vehicles with surrounding area monitoring
Some vehicle functions require the vehicle’s path
to be detected and evaluated. This is done by
cameras installed permanently on the vehicle
that detect objects in the vehicle's surroundings
(such as obstacles or guard rails). The live images
from the cameras are transmitted to the applica-
ble control module.
The camera images are transmitted to the appli-
cable control module and stored for processing.
The control module analyzes the current camera
image using image evaluation software. This im-
age evaluation software detects anonymized
technical measurements, such as distances to ob-
jects. The control module evaluates these techni-
cal measurements and makes it possible for the
assist systems to control the vehicle, if necessary.
Data memories
~ 3. o
g| =z x a.


Fig. 188 Driver's side footwell: connection port for the On
Board Diagnostic System (OBD)
Your vehicle is equipped with electronic control
modules for various vehicle systems such as the
airbags. These vehicle control modules store data
while driving normally that is required by an au-
thorized Audi dealer or authorized Audi Service
Facility for diagnosis and repair purposes. Only
certain types of data are recorded for a very short
period of time if a control module has detected a
system event. No noises, conversations, or im-
ages will be recorded in the vehicle.
The data may include information such as the ve-
hicle speed, the direction of travel, and informa-
tion about the brake system, or also the behavior
of the restraint system in the event of an acci-
dent. The stored data can be exported and down-
loaded with special devices, which must be con-
nected directly to the vehicle.
On Board Diagnostic System (OBD)
There is a diagnostic connector socket in the driv-
er's side footwell to read out the various control
modules and the event data recorder. Data re-
garding the function and condition of the elec-
tronic control modules is stored in the event
memory. Only have an authorized Audi dealer or
authorized Audi Service Facility read out and de-
lete the event memory.

ZX WARNING
— Incorrect use of the connection port for the
On Board Diagnostic System can cause mal-
functions, which can then result in accidents
and serious injuries.
— Only allow an authorized Audi dealer or au-
thorized Audi Service Facility to read out the
engine data.
ash data recorder
Event Data Recorder


This vehicle is equipped with an Event Data Re-
corder (EDR). The main purpose of an EDR is to
record, in certain crash or near crash-like situa-
tions,
such as an airbag deployment or hitting a
road obstacle, data that will assist in understand-
ing how a vehicle's system performed. The EDR is
designed to record data related to vehicle dynam-
ics and safety systems for a short period of time,
typically 30 seconds or less. The EDR in this vehi-
cle is designed to record such data as:
277

8W1012721BC
Accessories and technical changes

Accessories and
technical changes
Warranty
Your vehicle is covered by various warranties:
— New Vehicle Limited Warranty
— Limited Warranty Against Corrosion Perforation
— Emissions Control System Warranties: Federal
Emissions Control System Defect Warranty,
Federal Emissions Performance Warranty
— Applies to: USA models: Kansas Safety Belt
Limited Warranty
— Applies to: USA models: California Emissions
Control Warranties: Short-term Emissions De-
fects Warranty, Long-term Emissions Defects
Warranty, TZEV models Emissions Defects
Warranty, California Emissions Performance
Warranty
You can find detailed information in your Warran-
ty & Maintenance Booklet and in the California
Emissions Booklet*.
Audi Literature Shop
Service information is made available as soon as
possible after a model is introduced and can be
ordered in the Audi Literature Shop: http://
literature.audiusa.com
Driving in other
countries
Government regulations in the United States and
Canada require motor vehicles to comply with
emissions regulations and safety standards.
Therefore, vehicles that were produced for the
U.S. and Canadian markets are different from
vehicles produced for other countries.
If you plan to use your vehicle outside of the
United States or Canada, it is possible that:
— Fuel may have a significantly lower octane rat-
ing. Unsuitable fuels can cause engine damage.
— Proper maintenance and repair work may not
be possible because special service equipment,
tools, or measuring devices needed for your ve-
hicle may not be available.
— Replacement parts may not always be availa-
ble.
— Navigation systems for vehicles built for the
U.S.A. and Canada will not necessarily work in
Europe, and may not work in other countries.
() Note
Audi is not liable for damage to the vehicle re-
sulting from these country-specific differen-
ces.
Maintenance, repairs,
and technical modifi-
cations
Observe the safety precautions > page 221, Gen-
eral information and > page 264, Raising the ve-
hicle.
General information
Due to the increasing complexity of technology in
these vehicles, as well as the safety and environ-
mental standards that apply, you can only per-
form a very limited amount of repairs and modifi-
cations to the vehicle yourself.
Proof of maintenance work may be required to
submit a claim within the warranty period.
We recommend that you have your vehicle serv-
iced by an authorized Audi dealer or authorized
Audi Service Facility and that Audi Genuine Parts
and Audi Genuine Accessories are used. This
helps to ensure that your vehicle's functionality,
performance, and safety are not impaired.
Maintenance and repairs
Your vehicle was designed to help keep mainte-
nance requirements to a minimum. Some regular
maintenance is required to help ensure that your
vehicle runs in a safe, economical, and reliable
manner. Please refer to your Warranty & Mainte-
nance Booklet for more detailed information
about vehicle maintenance.
When operating the vehicle under more extreme
operating conditions, for example when outside
temperatures are very low or in very dusty envi-
ronments, certain maintenance should be per-
formed between the specified intervals.
281

Accessories and technical changes

Usually maintenance and repair work requires
special tools, measuring devices, and other
equipment that is available to trained vehicle
technicians in order to help ensure that your vehi-
cle and all of its systems operate correctly, relia-
bly, and safely. Performing work on the vehicle
incorrectly can impair the operation and reliabili-
ty of your vehicle and may void one or more of
your vehicle's warranties.
Technical Modifications
Interference with electronic components, their
software, the wiring, and data transfer may cause
malfunctions. Because of the way electronic com-
ponents are interconnected, such malfunctions
can also impair systems that are not directly in-
volved. This means that you risk both a substan-
tial reduction in the operational safety of your ve-
hicle and increased wear of vehicle components.
Some convenience functions, such as the conven-
ience turn signal function, individual door open-
ing function, and displays, can be reprogrammed
using special workshop equipment. If functions
are reprogrammed, the information and descrip-
tions about these functions in this Owner's Man-
ual may no longer apply to the changed func-
tions. Audi recommends that an authorized Audi
dealer or authorized Audi Service Facility perform
and verify any reprogramming procedures.


— Never perform any work in the engine com-
partment unless you know exactly how to
carry out the job and have the correct tech-
nical information and the correct tools.
— If you are uncertain about what to do, have
the work performed by an authorized Audi
dealer, an authorized Audi Service Facility,
or another qualified workshop. Serious per-
sonal injury may result from improperly per-
formed work.


ZA\ WARNING
Maintenance work, repairs, or technical modi-
fications to the vehicle (such as installing ad-
ditional equipment) that is not performed
correctly can cause serious injuries and in-
crease the risk of an accident.


Z\ WARNING
The engine compartment in any motor vehicle
is a potentially dangerous area and can cause
serious personal injury.
— Always use extreme caution when doing any
work in the engine compartment. Always
follow commonly accepted safety practices
and use common sense. Never risk personal

injury.

282
@) Note
— Maintenance work, repairs, or technical
modifications to the vehicle (such as instal-
ling additional equipment) that is not per-
formed correctly can cause vehicle damage.
— If emergency repairs must be performed,
take your vehicle to an authorized Audi deal-
er or authorized Audi Service Facility as soon
as possible.
— Audi is not liable for damage to the vehicle
resulting from failure to comply with these
guidelines.
@) For the sake of the environment
— Regular maintenance can help protect the
environment.
— Technical modifications to the vehicle can
have a negative impact on fuel consumption
and vehicle emissions.
@) For the sake of the environment
Certain components in your vehicle such as
undeployed airbag modules, pretensioners
and remote control batteries may contain Per-
chlorate Material - special handling may ap-
ply, See www.dtsc.ca.gov/hazardouswaste/
perchlorate. When the vehicle or parts of the
restraint system including airbag modules
and safety belts with pretensioners are scrap-
ped, all applicable laws and regulations must
be observed. Your authorized Audi dealer is
familiar with these requirements and we rec-
ommend that you have your dealer perform
this service for you.