2021 AUDI A7 check engine light

4K8012721BF
Checking and Filling

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.
Catalytic converter
Observe the safety precautions > page 259, Gen-
eral 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.
Engine compartment
General information
Special care is required if you are working in the
engine compartment
For work in the engine 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\.
Explanation of warnings (sticker in the engine
compartment):

Hot engine components!
Rotating parts!

The radiator fan can switch on at any
time!

High voltage! Switch off the engine be-
fore coming into contact with any igni-
tion system components!

Applies to: vehicles with plug-in hybrid
drive: High voltage! The voltage in the
high-voltage system is high enough to
cause fatal injuries. Touching a damaged
high-voltage component can result ina
fatal electric shock.

The catalytic converter can be damaged
"271 if the oil level is too high!
oy
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.

Always follow the instructions in the op-
erating manual.



259

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Checking and Filling

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.



RAZ-0016|

Fig. 163 Unlocked hood: lever
Make sure the wiper arms are not raised up from
the windshield. Otherwise the paint could be
damaged.
Opening the hood
> Applies to: vehicles with plug-in hybrid drive:
Switch the ignition off before releasing the
hood so that the gasoline engine does not start
automatically.

2) The &> symbol is not available in all countries.
> With the door open, pull the lever 2 below
the instrument panel in the direction of the ar-
row > fig. 162.
>» Raise the hood slightly > page 259.
> Press the lever > fig. 163 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 strut.
> Let the hood fall lightly into the latch. Do not
press it in. > JX.
Messages
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
latched 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.
— If you notice that the hood is not latched
while you are driving, stop immediately and
close it, because driving when the hood is
not latched increases the risk of an accident.


261

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Checking and Filling

If engine oil that meets the recommended speci-
fication is not available, in an emergency you
may add a maximum of 1 quart (1 liter) of
ACEA C3 or API SN engine oil one time until the
next oil change.
For more information on the correct engine oil
for your vehicle, contact an authorized Audi deal-
er or authorized Audi Service Facility. Have the oil
changed by an authorized Audi dealer or author-
ized Service Facility.
@ Tips
Audi recommends using engine oils provided
by Audi Genuine Parts.
Messages
Engine oil pressure
Biturn off engine. Oil pressure too low
Stop driving and switch the engine off. Check the
engine oil level > page 264.
—If the engine oil level is too low, add engine oil
=> page 264. 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
& Please add oil immediately.
Stop driving and switch the engine off. Check the
engine oil level > page 264 and add engine oil
immediately > page 264.
EJ Add max. x qt (xl) oil. You can continue
driving
Add the amount of oil shown immediately
=> page 264.
Reducing the oil level
EA 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
|.) 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.
B 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 7} is not an oil level
indicator. Always check the oil level regularly.
263

Checking and Filling


— Maintain enough distance when you are re-
moving the oil drain plug. While doing this,
keep your forearm parallel to the ground to
reduce the risk of hot oil dripping down your
arm.
— Drain the oil into a container designed for
this purpose that is large enough to hold the
full amount of oil in your engine.
— Engine oil is poisonous. Always store out of
reach of children.
— Prolonged contact of used engine oil with
the skin may cause skin damage. Always
wash oil off immediately with soap and wa-
ter to protect your skin.
@) 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 g indi-
cator light. However, occasionally checking the
coolant level is recommended.
Messages
& Turn off engine and check coolant level. See
owner's manual
266
The coolant level is too low.
Stop driving and switch the engine off. Check the
coolant level > page 267.
— If the coolant level is too low, add coolant
=> page 267. Only continue driving once the in-
dicator light turns off.
|_| 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
Audi dealer or authorized Audi Service Facility
for assistance.
|| 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.
Applies to: vehicles with plug-in hybrid drive
B Electric drive: malfunction! Cooling system.
Please contact Service
There is a malfunction in the cooling system.
Drive to an authorized Audi dealer or authorized
Audi Service Facility immediately.
Coolant additive
The coolant additive is made of anti-freezing and
corrosion protection agents. Only add the follow-
ing coolant additives mixed with distilled water.

Coolant additive Specification

G12evo TL774L

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.

Checking and Filling







4K8012721BF


additive tion 3
Warm min. 40% min. -13 °F @) mae s
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- MIN
ized Audi dealer or authorized Audi Service
Facility check if the coolant additive in your Fig. 166 Engine compartment - Coolant expansion tank:
vehicle matches the percentage appropriate @ cover with release button; @) markings
for the climate. This is especially important
when driving in colder climates. Observe the safety precautions > page 259, Gen-
— If the G12evo coolant additive is not availa- eral information.
ble in an emergency, do not add any other Applies to: vehicles with plug-in hybrid drive:
additive. You could damage the engine. If Your vehicle has two coolant expansion tanks
this happens, only use distilled water and that are separate from each other > page 262,
restore the correct mixture ratio with the fig. 164. One expansion tank for the combustion
specified coolant additive as soon as possi- engine and one tank for the high-voltage system.
ble. The coolant expansion tank for the high-voltage
— Only refill with new coolant. system is sealed and must not be opened > /\
— Radiator sealant must not be mixed with and> /\.
the coolant. .
— You can continue driving if the permitted Checking/the:coolantilevel
G12evo coolant additive was not added. > Park the vehicle on a level surface.
However, go to an authorized Audi dealer or > Switch the ignition off.
authorized Audi Service Facility immediately > Open the hood & page 261.
to have the coolant replaced to reduce the
risk of engine damage.
— 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.
The coolant expansion tank for some engines is
located in the water drip tray under a cover. Slide
the cover that is located below the windshield
wiper on the front passenger's side toward the
windshield and remove the cover.
> Check the coolant level in the coolant expan-
sion tank > page 262, fig. 164 using the outer
markings @) > fig. 166. 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.
> Conventional drive system: When you add cool-
ant to the expansion tank, please refer to
=> page 266, Cooling system.
> Plug-in hybrid drive: If you add coolant to the
coolant expansion tank for the combustion en-
gine, see > page 266, Cooling system.
> Plug-in hybrid drive: If coolant is missing from
the high-voltage system coolant expansion >
267

4K8012721BF
Checking and Filling

Brake fluid

BFV-0229]



Fig. 167 Engine compartment: cap on brake fluid reservoir
Observe the safety precautions > page 259, Gen-
eral information.
Checking the brake fluid level
> Slide the cover that is located below the wind-
shield wipers on the driver's side toward the
windshield and remove the cover.
> Read the brake fluid level on the brake fluid res-
ervoir > page 262, fig. 164. The brake fluid lev-
el must be between the MIN and MAX markings
of.
The brake fluid level is monitored automatically.
Messages
GG / @ Brakes: stop vehicle and check brake
fluid level
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 I / B or fl indicator light turns on,
there is a malfunction in the power supply, the
battery, or the vehicle electrical system.
/ BB Electrical system: malfunction! Safely
stop vehicle
Do not continue driving and switch the ignition
off > A\. See an authorized Audi dealer or author-
ized 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 or 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
269
>

Checking and Filling

Switch off all electrical equipment that is not
needed. If necessary, some equipment will be
switched off automatically. Vehicle functions or
driving stability may be limited. Drive to an au-
thorized 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. Do not continue driv-
ing and switch the ignition off. See an author-
ized Audi dealer or authorized Audi Service Fa-
cility for assistance.

Battery
Praia cela)
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 271, 12
Volt vehicle battery or > page 271, Other bat-
tery types
— Auxiliary battery (for example, for recuperation
or optional equipment) > page 271, Other bat-
tery types
— Plug-in hybrid drive: High-voltage battery (for
example, for electric driving) > page 119, In-
troduction.
270
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 limited or switched off. Some
convenience functions, such as interior lighting
or power seat adjustment, may not be available
under certain circumstances. The convenience
functions will be available again when you 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 272. Contact an authorized Audi dealer or
authorized Audi Service Facility for more infor-
mation.
Winter operation
Cold weather places an especially high load on
the 12 Volt vehicle battery. Have the battery
checked by an authorized Audi dealer or author-
ized Audi Service Facility before cold weather be-
gins.

ZA 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 a charging cable or jump
start cable directly to the 12 Volt vehicle
battery. Only use the connections in the en-
gine compartment > page 272.

ZX WARNING
California Proposition 65 Warning:
— 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.

Checking and Filling

arging the 12 Volt vehicle battery

Fig. 168 Engine compartment: connectors for a charger or
jump start cables
Observe the safety precautions > page 259, Gen-
eral information, > A\ in Battery general infor-
mation on page 270 and > /A\.
Requirement: only use chargers with a maximum
charging current of 14.8 volts. The battery ca-
bles remain connected.
The charging cable connections are located in the
motor compartment. The ground point ©) is al-
ways located on the vehicle body.
> Switch off the ignition and all electrical equip-
ment.
> Open the hood > page 261.
> Press the release lever on the positive terminal
and fold the cover upward > fig. 168.
> Clamp the charger terminal clamps to the jump
start pins according to the instructions. (Hex
head bolt under a cover @), ground point on the
vehicle body ©)).
> 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 261.

Z\ WARNING
— Never connect a charging cable or jump
start cable directly to the 12 Volt vehicle
battery. Only use the connections in the en-
gine compartment > page 272.

272

— 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.

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

B4M-0135)


Fig. 169 Engine compartment: washer fluid reservoir cap
Observe the safety precautions > page 259, Gen-
eral information.
The windshield washer reservoir © contains the
cleaning solution for the windshield and the
headlight washer system* > fig. 169,
=> page 262. The reservoir capacity can be found
in > page 332.
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.