check engine light AUDI S4 2020 User Guide

8W1012721BB
Checking and Filling

@) Tips
The fuel filler door on your vehicle does not
lock if you lock the vehicle from the inside us-
ing
the central locking switch.

Fuel filler door emergency release
If the central locking system malfunctions, the
fuel filler door can be unlocked manually.

Fig. 158 Right side trim panel in the luggage compart-
ment: opening the trim panel

Fig. 159 Luggage compartment: fuel filler door emergency
release
The emergency opening mechanism is located
behind the right side trim panel in the luggage
compartment.
> Open the cover in the side panel > fig. 158.
> To unlock the fuel filler door, loosen the loop
from the retainer and then pull on the loop
carefully > fig. 159 >@).
> Press on the left side of the fuel filler door to
open it > page 211, fig. 156.
® Note
Only pull on the loop until you feel resistance.
You will not hear it release. If you continue to

pull, you could damage the emergency re-
lease mechanism.
Emissions control
system
General information
ZA\ WARNING
The temperature of the exhaust system is
high, both when driving and after stopping
the engine.

— Never touch the exhaust tail pipes once they
have
become hot. This could result in burns.
— Do not park your vehicle over flammable
materials such as grass or leaves because
the high temperature of the emissions sys-
tem could start a fire.
— Do not apply underbody protectant in the
exhaust system area, because this increases
the risk of fire.
(ele) Nidtml alg
Follow the safety precautions > page 213, Gener-
al information.

The vehicle may only be driven with unleaded
gasoline, or the catalytic converter will be de-
stroyed.
Never drive until the tank is completely empty.
The irregular supply of fuel that results from that
can cause engine misfires. Uncombusted fuel
could enter the exhaust system, which could
cause overheating and damage to the catalytic
converter.

Malfunction Indicator Lamp (MIL)
If the S indicator light blinks or turns on, there
is a malfunction that is causing poor emissions
quality and that could damage the catalytic con-
verter. Drive slowly to an authorized Audi dealer
or authorized Audi Service Facility to have the
malfunction corrected.
213

Checking and Filling

The indicator light can also turn on if the fuel fill-
er cap is not closed correctly > page 211).
Engine compartment
General information
Special care is required if you are working in the
motor compartment
For work in the motor compartment, such as
checking and filling fluids, there is a risk of in-
jury, scalding, accidents, and burns. For this
reason, follow all the warnings and general
safety precautions provided in the following in-
formation. The engine compartment is a dan-
gerous area in the vehicle. > A.


ZA WARNING
— Turn the engine off.
— Switch the ignition off.
— Set the parking brake.
— Select the “P” (Park) selector lever position.
— Allow the engine to cool.
— Keep children away from the engine com-
partment.
— Never spill fluids on a hot engine. These flu-
ids (such as the freeze protection contained
in the coolant) can catch fire.
— Avoid short circuits in the electrical system.
— Never reach into the radiator fan. The fan is
temperature-controlled and can turn on
suddenly, even when the ignition is switched
off.
— Never open the hood when there is steam or
coolant escaping from the engine compart-
ment, because there is a risk that you could
be burned. Wait until no steam or coolant is
escaping.
— The cap on the coolant expansion tank must
never be opened when the coolant is hot.
The cooling system is under pressure. There
is a risk of burns
—To protect your face, hands, and arms from
hot steam or coolant, cover the cap with a
— Do not remove the engine cover under any
circumstances. This increases the risk of
burns.
— Due to the risk of electric shock, never touch
the ignition cable or other components in
the electronic high-voltage ignition system
when the engine is running or is starting.
— Ifa gear is engaged while the vehicle is sta-
tionary and the engine is running, do not
press the accelerator pedal inadvertently.
Pressing the accelerator pedal will cause the
vehicle to move, and this could result in an
accident.
— If inspections or repairs must be performed
while the engine is running, moving compo-
nents (such as the ribbed belt, generator,
and radiator fan) pose an additional risk.
— Set the parking brake first and select the
“P” (Park) selector lever position.
— Always make sure that no parts of the
body, jewelry, ties, loose clothing, and
long hair can be caught in moving engine
components. Before any work, always re-
move any jewelry and/or ties, tie back long
hair, and make sure all clothing fits close
to the body to reduce the risk of anything
becoming caught in engine components.
— Pay attention to the following warnings list-
ed when work on the fuel system or on the
electrical equipment is required.
— Do not smoke.
— Never work near open flames.
— Always have a working fire extinguisher
nearby.
— All work on the battery or electrical system
in your vehicle can result in injuries, chemi-
cal burns, accidents, or burns. Because of
this, all work must be performed only by an
authorized Audi dealer or authorized Audi
Service Facility.
— Limit your exposure to exhaust and chemi-
cals to as short a time as possible.




thick cloth when opening.


ZA\ WARNING
California Proposition 65 Warning:


1) Depending on the engine and country
214

8W1012721BB
Checking and Filling


— Engine exhaust, some of its constituents,
and certain vehicle components contain or
emit chemicals known to the State of Cali-
fornia to cause cancer and birth defects and
reproductive harm. In addition, certain flu-
ids contained in vehicles and certain prod-
ucts of component wear contain or emit
chemicals known to the State of California
to cause cancer and birth defects or other
reproductive harm.
— Battery posts, terminals and related acces-
sories contain lead and lead compounds,
chemicals known to the State of California
to cause cancer and reproductive harms.
Wash hands after handling.
Q Note
When filling fluids, be sure not to add any flu-
ids to the wrong reservoirs. Otherwise severe
malfunctions and engine damage will occur.


@ For the sake of the environment
You should regularly check the ground under
your vehicle in order to detect leaks quickly. If
there are visible spots from oil or other fluids,
bring your vehicle to an authorized Audi deal-
er or authorized Audi Service Facility to be
checked.
Opening and closing the hood
The hood is released from inside the vehicle.


Fig. 160 Footwell: release lever

Fig. 161 Unlocked hood: lever
Make sure the wiper arms are not raised up from
the windshield. Otherwise the paint could be
damaged.
Opening the hood
> With the door open, pull the lever > below
the instrument panel in the direction of the ar-
row > fig. 160.
> Raise the hood slightly > /A\.
> Press the lever > fig. 161 in the direction of the
arrow. This releases the hooks.
> Open the hood.
Closing the hood
> Push the hood down until you override the
force of the struts.
> Let the hood fall lightly into the latch. Do not
press itin. > AX.
Message
B Warning! Hood is not locked. Stop vehicle
and check the lock
The hood latch is not locked correctly. Stop im-
mediately and close the hood.

ZX WARNING
— Never open the hood when there is steam or
coolant escaping from the engine compart-
ment, because there is a risk that you could
be burned. Wait until no steam or coolant is
escaping.
—For safety reasons, the hood must always be
closed securely while driving. Because of
this, always check the hood after closing it
to make sure it is latched correctly. The hood
is latched if the front corners cannot be lift-
ed. >

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Checking and Filling


Audi recommends
Sbastrol | ZIDIGE Prarzssional
Audi recommends using the LongLife high-per-
formance engine oil from Audi Genuine Parts.
I Tet
Engine oil pressure


i Turn off engine. Oil pressure too low
Stop driving and switch the engine off. Check the
engine oil level > page 217.
— If the engine oil level is too low, add engine oil
=> page 218. Only continue driving once the in-
dicator light turns off.
— If the engine oil level is correct and the indica-
tor light still turns on, turn the engine off and
do not continue driving. See an authorized Audi
dealer or authorized Audi Service Facility for as-
sistance.
Engine oil level
Applies to: vehicles with oil level warning
3 Please add oil immediately
Stop driving and switch the engine off. Check the
engine oil level > page 217 and add engine oil
immediately > page 218.
2 Please add max. x qt (x I) oil. You can con-
tinue driving
Add the amount of oil shown immediately
=> page 218.
Reducing the oil level
3 Please reduce oil level
There is too much oil in the engine and there is a
risk of damaging the catalytic converter or en-
gine. Drive to an authorized Audi dealer or au-
thorized Audi Service Facility immediately to have
engine oil extracted if necessary. Avoid high en-
gine speeds, full acceleration, and heavy engine
loads.
Engine oil sensor
2 Oil level sensor: oil change necessary. Please
contact Service
Fuel has entered the engine oil. This will cause
the engine oil level to rise slowly and the engine
oil quality to decrease. Do not extract engine oil
to reduce the level, because this will increase the
risk of engine damage. Drive to an authorized
Audi dealer or authorized Audi Service Facility im-
mediately to have engine oil extracted.
& Oil level system: malfunction! Please con-
tact Service
The sensor that checks the engine oil level has
malfunctioned. Drive immediately to an author-
ized Audi dealer or authorized Audi Service Facili-
ty to have the malfunction repaired.
& Oil pressure sensor: malfunction! Please
contact Service
The sensor that checks the engine oil pressure
has malfunctioned. Drive immediately to an au-
thorized Audi dealer or authorized Audi Service
Facility to have the malfunction repaired.
Engine warm-up request
i Please drive to warm up engine
Fuel has entered the engine oil, either due to low
outside temperatures or frequent short drives.
Drive until the engine is warm so that the fuel in
the engine oil will evaporate. Avoid high engine
speeds, full accelerating, and heavy engine loads
when doing this.
G@) Tips
The oil pressure warning EE is not an oil level
indicator. Always check the oil level regularly.
Checking the engine oil level
The engine oil level can be checked in the MMI.
Observe the safety precautions > A\ in General
information on page 214.
> Park the vehicle on a level surface.
» Shut the engine off when it is warm.
> Switch only the ignition back on.
> Wait approximately two minutes.
> Applies to: MMI: Select on the home screen:
VEHICLE > Settings & Service > Oil level.
217
>

Checking and Filling

@) Note
Do not mix any additives with the engine oil.
Additives may cause engine damage that is
not covered by your New Vehicle Limited War-
ranty.
@ For the sake of the environment
— Before changing the engine oil, make sure
you can dispose of the used engine oil cor-
rectly.
— Engine oil must always be disposed of cor-
rectly. Do not dump it in the yard, in the for-
est, or in open water, river channels, or sew-
ers.
— Have your used engine oil recycled by bring-
ing it to a used oil collection site or contact
a gas station.
Cooling system
The engine cooling system is filled with a mixture
of purified water and coolant additive at the fac-
tory. This coolant must not be not changed.
The coolant level is monitored using the B indi-
cator light. However, occasionally checking the
coolant level manually is recommended.
Messages
& Turn off engine and check coolant level. See
owner's manual
The coolant level is too low.
Stop driving and switch the engine off. Check the
coolant level > page 221.
— If the coolant level is too low, add coolant
=> page 221. Only continue driving once the in-
dicator light turns off.
gg Coolant temperature: too high. Please let
engine run while vehicle is stationary
Let the engine run at idle for a few minutes to
cool off, until the indicator light turns off.
— If the indicator light does not turn off, do not
continue driving the vehicle. See an authorized
220
Audi dealer or authorized Audi Service Facility
for assistance.
/E| Coolant system: malfunction! Please turn
off engine
Do not continue driving, shut the engine off, and
switch the ignition off.
— See an authorized Audi dealer or authorized
Audi Service Facility for assistance.
Coolant additive
The coolant additive is made of anti-freezing and
corrosion protection agents. Only use the follow-
ing coolant additives. These additives may be
mixed with each other.




Coolant additive Specification
Gl12evo TL774L
G12++ TL774G
G13 TL774])

The amount of coolant additive that needs to be
mixed with water depends on the climate where
the vehicle will be operated. If the coolant addi-
tive percentage is too low, the coolant can freeze
and damage the engine.

Coolant Freeze protec-
additive tion
Warm min. 40% min. -13 °F
regions max. 45% (-25 °C)
Cold min. 50% max. -40 °F
regions max. 55% (-40 °C)

@) Note
— Before the start of winter, have an author-
ized Audi dealer or authorized Audi Service
Facility check if the coolant additive in your
vehicle matches the percentage appropriate
for the climate. This is especially important
when driving in colder climates.
— If the appropriate coolant additive is not
available in an emergency, do not add any
other additive. You could damage the en-
gine. If this happens, only use water and re-
store the correct mixture ratio with the
specified coolant additive as soon as possi-
ble.

8W1012721BB
Checking and Filling

— Only refill with new coolant.
— Radiator sealant must not be mixed with
the coolant.
— Due to the risk of engine damage, the cool-
ing system should only be refilled by an au-
thorized Audi dealer or authorized Audi
Service Facility. An authorized Audi dealer or
authorized Audi Service Facility can also pro-
vide you with important information about
the recommended coolant additive.


RAZ-0540


MIN

Fig. 164 Engine compartment - coolant expansion tank: @
cover; (2) markings
Follow the safety precautions > page 214, Gener-
al information.
Checking the coolant level
> Park the vehicle on a level surface.
> Switch the ignition off.
> Open the hood > page 215.
The coolant expansion tank for some engines is
located in the water drip tray under a cover. If
necessary, remove the cover that is located under
the windshield wiper on the front passenger's
side.
> Check the coolant level in the coolant expan-
sion tank > page 216, fig. 162 using the outer
markings (2) > fig. 164. The coolant level must
be between the markings (2) when the engine is
cold. When the engine is warm it can be slight-
ly above the upper marking.
>» Applies to: vehicles with 6-cylinder engine:
There is a float located in the coolant expansion
tank. Read the coolant level using the coolant
level float. When the engine is cold, the float
must be located between the MIN marking and
the edge of the filler opening on the coolant ex-
pansion tank.
Adding coolant
Requirement: there must be a residual amount of
coolant in the expansion tank >(@).
If you must add coolant, use a mixture of water
and coolant additive. Mixing the coolant additive
with distilled water is recommended.
> Allow the engine to cool.
>» Place a large, thick towel on the coolant expan-
sion tank cap.
> Push the release button @) © fig. 164 on the
cap and carefully turn it to the left until you
feel resistance > /\.
> Push the release button again and remove the
cap completely.
> Add coolant in the correct mixture ratio
=> page 220 up to the MAX marking. Or, in
vehicles with a 6-cylinder gasoline engine, the
float must be located between the MIN mark-
ing and the edge of the filler opening on the
coolant expansion tank.
> Make sure that the fluid level remains stable.
Add more coolant if necessary.
> Vehicles with 6-cylinder engine: if necessary,
press the float into the coolant expansion tank
using the cover.
> 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.

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 214, General informa-
tion.
— Never open the hood if you can see or hear
steam or coolant escaping from the engine >

221

Checking and Filling


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 continue driving if the coolant expan-
sion tank is empty. Do not add any coolant,
because air could enter the cooling system
and damage the engine. See an authorized
Audi dealer or authorized Audi Service Facility
for assistance.


Brake fluid

BFV-0229)


Fig. 165 Engine compartment: cap on brake fluid reservoir
Follow the safety precautions > page 214, Gener-
al information.
Checking the brake fluid level
Read the brake fluid level on the brake fluid res-
ervoir > page 216, fig. 162. The brake fluid level
must be between the MIN and MAX markings
SA.
The brake fluid level is monitored automatically.
Message
Ga y @ Brakes: stop vehicle and check brake
fluid level
222
Stop the vehicle and check the brake fluid level.
See an authorized Audi dealer or authorized Audi
Service Facility for assistance.
Changing the brake fluid
Brake fluid should be changed at regular inter-
vals. Have the brake fluid changed by an author-
ized Audi dealer or authorized Audi Service Facili-
ty. The authorized Audi dealer or authorized Audi
Service Facility will inform you of the replace-
ment intervals.

Z\ WARNING
— If the brake fluid level is below the MIN
marking, it can impair the braking effect and
driving safety, which increase the risk of an
accident. Do not continue driving. See an au-
thorized Audi dealer or authorized Audi
Service Facility for assistance.
— If the brake fluid is old, bubbles may form in
the brake system during heavy braking. This
could impair braking performance and driv-
ing safety, which increases the risk of an ac-
cident.
— The brake fluid in your vehicle must meet
the standard VW 501 14 and is available at
an authorized Audi dealer or authorized
Audi Service Facility. If this brake fluid is not
available, another high-grade brake fluid of
equivalent quality may be used, and it must
meet
the U.S. Federal Motor Vehicle Stand-
ard (FMVSS) 116 DOT 4, Class 6.

@) Note
— If the brake fluid level is above the MAX
marking, brake fluid may leak out over the
edge of the reservoir and result in damage
to the vehicle.
— Do not allow any brake fluid to come into
contact with the vehicle paint, because it
will corrode the paint.
Electrical system
If the =z or fm] indicator light turns on, there is a
malfunction in the generator, the battery, or the
vehicle electrical system.

8W1012721BB
Checking and Filling

a Electrical system: malfunction! Safely stop
vehicle
Do not continue driving and switch the engine off
=> AX. See an authorized Audi dealer or authorized
Audi Service Facility for assistance.
= Electrical system: malfunction! Restart not
possible. Please contact Service
If you switch the ignition off, you will not be able
to restart the vehicle. Vehicle functions/driving
stability may be limited. Drive to an authorized
Audi dealer or authorized Audi Service Facility im-
mediately.
= Electrical system: malfunction! Please con-
tact Service
Switch off all electrical equipment that is not
needed. Vehicle functions/driving stability may
be limited. Drive to an authorized Audi dealer or
authorized Audi Service Facility immediately.
= Electrical system: low battery charge. Bat-
tery will be charged while driving
The starting ability may be impaired.
If this message turns off after a little while, the
vehicle battery has charged enough while driving.
If this message does not turn off, drive immedi-
ately to an authorized Audi dealer or authorized
Audi Service Facility.

ZA WARNING
When there is an electrical system malfunc-
tion, vehicle functions may not work and driv-
ing stability may be limited, which increases
the risk of an accident. Stop driving and
switch the engine off. See an authorized Audi
dealer or authorized Audi Service Facility for
assistance.

Battery
Peale mee eee scl)
Because of the complex power supply, all work on
batteries such as disconnecting, replacing, etc.,
should only be performed by an authorized Audi
dealer or authorized Audi Service Facility > A\.
Multiple batteries with different technologies
may be installed in your vehicle:
— Vehicle battery (for example, for starting the
engine, basic power supply) > page 224, Lead
battery or > page 224, Other battery types
— Auxiliary battery (for example, for recuperation
or optional equipment) > page 224, Other bat-
tery types
Not running the vehicle for long periods of
time
The battery will gradually drain if the vehicle
does not run for long periods of time. To ensure
that the vehicle can still be started, the electrical
equipment will be reduced or switched off
= page 99. Some convenience functions, such as
interior lighting or power seat adjustment, may
not be available under certain circumstances.
These convenience functions will be available
again once you switch the ignition on and start
the
engine.
Even when electrical equipment is switched off,
the equipment can still drain the battery if the
vehicle is not driven for long periods of time.
Deep draining results in a chemical reaction that
destroys the inside of the battery. The battery
must be charged every month to prevent this
= page 225. Contact an authorized Audi dealer or
authorized Audi Service Facility for more infor-
mation.
Winter operation
Cold weather places higher demands on the bat-
tery. This results in reduced starting ability. Have
the battery checked by an authorized Audi dealer
or authorized Audi Service Facility before cold
weather begins.

Z\ WARNING
— All work on the battery or electrical system
in your vehicle can result in injuries, chemi-
cal burns, accidents, or burns. Because of
this, all work must be performed only by an
authorized Audi dealer or authorized Audi
Service Facility.
— Never connect the charging cable or jump
start cable directly to your vehicle battery. >

223

8W1012721BB
Checking and Filling

a ing the battery

Fig. 166 Engine compartment: connectors for a charger or
jump start cables
Note the safety precautions > page 214, General
information, > A\ in Battery general informa-
tion on page 223 and > /\.
Requirement: only use chargers with a maximum
charging current of 14.8 volts. The battery ca-
bles remain connected.
The battery is located in the engine compart-
ment. The ground point ©) is always located on
the vehicle body.
> Switch off the ignition and all electrical equip-
ment.
> Open the hood > page 215.
> Press the release lever on the positive terminal
and fold the cover upward > fig. 166.
> Clamp the charger terminal clamps to the jump
start pins according to the instructions. (Pin un-
der the cover = “positive”).
> Insert the power cable for the charging device
into the socket and switch the device on.
> At the end of the charging process, switch the
charger off and pull the power cable out of the
socket.
» Remove the charging device terminal clamps.
> Close the cover on the positive terminal.
> Close the hood > page 215.

ZX WARNING
— Never connect the charging cable directly to
your vehicle battery. Only use the connec-
tions in the engine compartment
=> page 225.

— A highly explosive mixture of gases can form
when charging batteries. Only charge the
battery in well-ventilated areas.
— A drained battery can freeze at tempera-
tures around 32 °F (0 °C). Do not charge or
use a frozen or thawed battery. If ice forms,
the battery housing can crack and battery
electrolyte can leak out, which increases the
risk of an explosion and chemical burns.
Contact an authorized Audi dealer or author-
ized Audi Service Facility for more informa-
tion.
— Do not connect or disconnect the charging
cable while charging because this increases


the risk of an explosion.

G) Tips
Read all of the manufacturer's instructions
for the charger before charging the battery.
Windshield washer
system

B8W-0125


Fig. 167 Engine compartment: washer fluid reservoir cap
Follow the safety precautions > page 214, Gener-
al information.
The windshield washer fluid reservoir © contains
the cleaning solution for the windshield and the
headlight washer system > fig. 167, > page 216.
The reservoir capacity can be found in
=> page 278.
To reduce the risk of lime scale deposits on the
spray nozzles, use clean water with low amounts
of calcium. Always add window cleaner to the wa-
ter. When the outside temperatures are cold, an
anti-freezing agent should be added to the water
so that it does not freeze.
225
>

Checking and Filling

Messages
3 Please add washer fluid
Fill the washer fluid for the windshield washer
system and the headlight washer system* when
the ignition is switched off.
@) Note
— The concentration of anti-freezing agent
must be adjusted to the vehicle operating
conditions and the climate. A concentration
that is too high can lead to vehicle damage.
— Never add radiator anti-freeze or other addi-
tives to the washer fluid.
— Do not use a glass cleaner that contains
paint solvents, because this could damage
the paint.
Service interval display
The service interval display detects when your ve-
hicle is due for service.
The service interval display works in two stages:
— Inspection or oil change reminder: after driv-
ing acertain distance, a message appears in the
instrument cluster display each time the igni-
tion is switched on or off. The remaining dis-
tance or time is displayed briefly.
— Inspection or oil change due: if your vehicle
has reached an inspection or oil change interval
or both intervals at the same time, the mes-
sage Inspection due! or Oil change due! or Oil
change and inspection due! will appear briefly
after switching the ignition on or off.
Checking service intervals
You can check the remaining distance or time un-
til the next oil change or next inspection in the
Infotainment system.
Select on the home screen: VEHICLE > Settings
& Service > Service intervals.
Resetting the indicator
An authorized Audi dealer or authorized Audi
Service Facility will reset the service interval dis-
play after performing service.
226
If you have changed the oil yourself, you must re-
set the oil change interval.
Select on the home screen: VEHICLE > Settings
& Service > Service intervals > Reset oil change
interval.
@) Note
— Only reset the oil change indicator if the oil
was changed.
— Following the service intervals is critical to
maintaining the service life and value of
your vehicle, especially the engine. Even if
the mileage on the vehicle is low, do not ex-
ceed the time for the next service.