2020 AUDI A3 heater

High-voltage system

High-voltage system
General information
Introduction
Applies to: vehicles with plug-in hybrid drive
All work done on the high-voltage system must
only be performed by certified high-voltage tech-
nicians at authorized Audi dealers or authorized
Audi Service Facilities in accordance with Audi
guidelines.
The high-voltage system is composed of the fol-
lowing high-voltage components, among other
things: the high-voltage battery, the power elec-
tronics, the electric motor, the high-voltage A/C
compressor, the high-voltage heater, the charg-
ing system and charging port, and the orange
high-voltage wiring.
The high-voltage battery is located on the vehicle
underbody in front of the rear axle and does not
require any maintenance from the driver.

ZA WARNING
The voltage in the high-voltage system is life-
threatening. Touching a damaged high-volt-
age component can result in a fatal electric
shock. The components in the high-voltage
system are marked with a warning label which
warns against the high-voltage.
— The voltage level in the high-voltage system
is still dangerous and potentially life-threat-
ening when the ignition is switched off.
— Never perform work on the orange high-
voltage cables or on other high-voltage
components. Only authorized repair facili-
ties that are certified may perform work on
the high-voltage system.
— Never damage, alter or remove the orange
high-voltage cable or disconnect it from the
high-voltage system.
— Never perform any work using cutting, shap-
ing or sharp-edged tools or heat sources
near the high-voltage system and high-volt-
age cables.
— Gases that escape from the high-voltage
battery can be poisonous or flammable.

96

— Damage to the high-voltage battery could
cause the high-voltage battery to leak im-
mediately or in the future, and poisonous or
flammable gases could escape. Do not in-
hale the gases!
— Do not expose yourself to any leaking fluids
and do not come into contact with them.
— The high-voltage battery electrolyte fluid is
caustic. If electrolyte fluid comes into con-
tact with the skin, flush the affected area for
at least 15 minutes with clean water. Then
wash the affected area with soap. Have the
affected area examined by a medical profes-
sional.
— In the event of a technical emergency, in-
form the responders that the vehicle is
equipped with a high-voltage battery.
@) Note
— The high-voltage system can be damaged if
the vehicle underbody comes into contact
with the ground. Immediately drive your ve-
hicle to an authorized repair facility and
have it inspected.
— The electric drive motor can become very
hot during operation. Do not stop the vehi-
cle if there is oil, fuel residue or other flam-
mable substances under or next to the vehi-
cle.
Special considerations for the high-voltage
battery
Applies to: vehicles with plug-in hybrid drive

Please first read and note the introductory infor-
mation and heed the warnings > page 96.
All batteries age with use and over time. There
are things you should know about the care of the
high voltage battery that will help it keep giving
you good service and reliability over time. Please
read and keep the following information in mind
while you enjoy the performance and economy of
your vehicle.
— Be sure to charge the high voltage battery be-
fore leaving the vehicle parked and unused for a
longer period of time. Ideally the high-voltage >

8V2012721BK
High-voltage system

battery should have a charge level between
40 % and 60 % when parked for a Long time.
If the battery charge level is below 3 %, never
park the vehicle for more than 21 days without
charging the high-voltage battery. Should you
have to park the vehicle for a long time, make
sure that the charge level is sufficient to help
prevent the battery from aging prematurely.
Frequent and consecutive charging of the high-
voltage battery when the charge level is above
98 % can also decrease the capacity of the
high-voltage battery. Make sure the charge lev-
el is below 98 % when you start the charging
process.
Should the vehicle be parked for longer than
2 days at temperatures below - 13 °F (-25 °C),
the high-voltage battery could freeze and not
be able to provide energy to the electric motor.
The battery will start working again, once it
warms up. The battery can be warmed up when
the outside temperature rises or when the vehi-
cle is garaged appropriately. The battery will al-
so warm up when being used (switching on the
air conditioner, the heater or by driving the ve-
hicle). Should you have to park your vehicle at
very low temperatures for longer than 1 day,
make sure that the high-voltage battery does
not freeze by parking the vehicle in a garage
that is heated or protected from the outside
temperature.
The high-voltage battery can be damaged and
the capacity can be decreased when the vehicle
is parked for longer than 24 hours when the
ambient temperature is higher than 118 °F
(48 °C). Always make sure that the high-voltage
battery is not exposed to temperatures above
118 °F (48 °C) for a long time.
Never park the vehicle in areas that are likely to
be flooded, such as beaches or river banks, and
never drive the vehicle in WATER, on flooded
roads or through water that is higher than the
bottom of the vehicle body. The high-voltage
battery, along with other vehicle components,
can be damaged severely if the high-voltage
battery is exposed to open water especially for
a longer time. However, you can drive through
water on roads under certain conditions
=> page 90.
Failure to heed any of these requirements can
age the battery prematurely and lead to a perma-
nent decrease of the high-voltage battery’s ca-
pacity.
G@) Tips
Always make sure that the high-voltage bat-
tery is not exposed to extremely low and high
temperatures as well as to water especially
for a longer time. Failure to protect and care
for the high voltage battery can lead to seri-
ous damage and/or a decrease of the capacity
void coverage under the New Vehicle Limited
Warranty.
Vehicle transport
Applies to: vehicles with plug-in hybrid drive
This section contains information you should
know about transporting your vehicle.
A lithium-ion high-voltage battery system equip-
ped in your vehicle has passed test 38.3 in ac-
cordance with the UN Tests and Criteria hand-
book and is manufactured in accordance with a
quality management program. The vehicle may
be transported with the high-voltage battery in-
stalled as conventional class 9 hazardous materi-
als without additional official authorization for
air and sea shipment (current law IATA-DGR and
IMDG code 01.01.2019).
Charging the high-
voltage battery
General information
Applies to: vehicles with plug-in hybrid drive
Two options are available for charging the vehi-
cle:
— Charge at a public charging station with a spe-
cial charging cable* > page 100.
— Charge with household and industrial* sockets
using the Audi charging system > page 101.
Using the charging equipment
Pay attention to the following information for
safe handling of the charging equipment:
97

8V2012721BK
Airbag system

the seat may prevent the Advanced Airbag Sys-
tem for the front passenger seat from doing its
job ina crash.
The front Advanced Airbag System consists
of the following:
— Crash sensors in the front of the vehicle that
measure vehicle acceleration/deceleration to
provide information to the Advanced Airbag
System about the severity of the crash.
— An electronic control unit, with integrated
crash sensors for front and side impacts. The
control unit “decides” whether to fire the front
airbags based on the information received from
the crash sensors. The control unit also “de-
cides” whether the safety belt pretensioners
should be activated.
— An Advanced Airbag with gas generator for the
driver inside the steering wheel hub.
— An Advanced Airbag with gas generator inside
the instrument panel for the front passenger.
— A capacitive passenger detection system under-
neath the front passenger seat cover. This sys-
tem measures the electrical capacitance of the
person in the seat. The information registered
is sent continuously to the electronic control
unit to regulate deployment of the front Ad-
vanced Airbag on the passenger side.
— An airbag monitoring system and indicator
light in the instrument cluster > page 265.
—Asensor in each front seat registers the dis-
tance between the respective seat and the
steering wheel or instrument panel. The infor-
mation registered is sent continuously to the
electronic control unit to regulate deployment
of the front Advanced Airbags.
— The PASSENGER AIR BAG OFF light comes on
and stays on in the center of the instrument
panel > page 304 and tells you when the front
Advanced Airbag on the passenger side has
been turned off.
—Asensor in the safety belt latch for the driver
and for the front seat passenger that senses
whether that safety belt is latched or not and
transmits this information to the electronic
control unit.


ZA WARNING
Damage to the front passenger seat can pre-
vent the front airbag from working properly.
— Improper repair or disassembly of the front
passenger and driver seat will prevent the
Advanced Airbag System from functioning
properly.
— Repairs to the front passenger seat must be
performed by qualified and properly trained
workshop personnel.
— Never remove the front passenger or driver
seat from the vehicle.
— Never remove the upholstery from the front
Passenger Seat.
— Never disassemble or remove parts from the
seat or disconnect wires from it.
— Never carry sharp objects in your pockets or
put them on the seat. The capacitive passen-
ger detection mat in the front passenger
seat will not function properly if it is punc-
tured.
— Never carry things on your lap or carry ob-
jects on the front passenger seat. Such ob-
jects can
influence the capacitance regis-
tered by the capacitive passenger detection
system, so that incorrect information is pro-
vided to the airbag control unit.
— Never store items under the front passenger
seat. Parts of the Advanced Airbag System
under the passenger seat could be dam-
aged, preventing them and the airbag sys-
tem from working properly.
— Never place seat covers or replacement up-
holstery that have not been specifically ap-
proved by Audi on the front seats.
— Seat covers can prevent the Advanced Airbag
System from recognizing child restraints or
occupants on the front passenger seat and
prevent the side airbag in the seat backrest
from deploying properly.
—If a seat heater has been retrofitted or oth-
erwise added to the front passenger seat,
never install any child restraint system on
this seat.
— Never use cushions, pillows, blankets, or
similar items on the front passenger seat.
The additional layers prevent the capacitive

261

Airbag system


passenger detection system from accurately
measuring the capacitance of the child safe-
ty seat and/or the person on the seat and
thus keep the Advanced Airbag System from
working properly.
— Never place or use any electrical device
(such as a laptop, CD player, electronic
games device, power inverter or seat heater
for child seats) on the front passenger seat
if the device is connected to the 12-volt
socket or the cigarette lighter socket. Such
devices can influence the capacitance regis-
tered by the capacitive passenger detection
system, so that incorrect information is pro-
vided to the airbag control unit.
— If you must use a child restraint on the front
passenger seat and the child restraint man-
ufacturer's instructions require the use of a
towel, foam cushion or something else to
properly position the child restraint, make
certain that the PASSENGER AIR BAG OFF
light comes on and stays on whenever the
child restraint is installed on the front pas-
senger seat.
— If the PASSENGER AIR BAG OFF light does
not come on and stay on, immediately in-
stall child restraint in a rear seating position
and have the airbag system inspected by
your Audi dealer.


Z\ WARNING
If the front passenger seat gets wet, dry it im-
mediately.
— If liquid soaks into the front passenger seat,
this can keep the airbag system from work-
ing properly and may, for instance, deacti-
vate the passenger frontal airbag. If this
happens, the PASSENGER AIR BAG OFF
light will come on and stay on together with
the airbag indicator light Ea in the instru-
ment cluster.
— If liquid is pooled on the seat, but has not
soaked in, this may also keep the airbag sys-
tem from working properly and cause the
passenger frontal airbag to be enabled
(turned on), even though there is a properly
installed child restraint system on the seat.
Wet towels or other wet things on the seat

cushion can have the same effect. If the
front passenger frontal airbag is turned on,
the PASSENGER AIR BAG OFF light will turn
off.

How the Advanced Airbag System
components work together
The front Advanced Airbag System and the side
airbags supplement the protection offered by the
front three-point safety belts and the adjustable
head restraints* to help reduce the risk of injury
in a wide range of accident and crash situations.
Be sure to read the important information about
safety and heed the WARNINGS in this chapter.
Deployment of the Advanced Airbag System and
the activation of the safety belt pretensioners de-
pend on the deceleration measured by the crash
sensors and registered by the electronic control
unit. Crash severity depends on speed and decel-
eration as well as the mass and stiffness of the
vehicle or object involved in the crash.
On the passenger side, regardless of safety belt
use, the front passenger frontal airbag will be
turned off if the electrical capacitance measured
by the capacitive passenger detection system on
the front passenger seat is less than the amount
programmed in the electronic control unit. The
front passenger frontal airbag will also be turned
off if the capacitance measured by the system for
the front passenger seat equals that of an infant
of about one year of age in one of the child seats
that was used to certify the Advanced Airbag Sys-
tem under Federal Motor Vehicle Safety Standard
208. The PASSENGER AIR BAG OFF light comes
on and stays on to tell you when the front Ad-
vanced Airbag System on the passenger side has
been turned off > page 265.

ZA WARNING
To reduce the risk of injury when an airbag in-
flates, always wear safety belts properly.
— If you are unrestrained, leaning forward, sit-
ting sideways or out of position in any way,
your risk of injury is much higher.
— You will also receive serious injuries and

could even be killed if you are up against the


262

Airbag system

The PASSENGER AIR BAG OFF light will show
the status of the front seat passenger's frontal
Advanced Airbag a few seconds after the igni-
tion is switched on and the airbag indicator
light goes off. The PASSENGER AIR BAG OFF
light:
— will stay on if the front passenger seat is not
occupied;
—will stay on if the electrical capacitance meas-
ured by the capacitive passenger detection sys-
tem for the front passenger seat equals the
combined capacitance of an infant up to about
one year of age and one of the rearward-facing
or forward-facing child restraints listed in Fed-
eral Motor Vehicle Safety Standard 208 with
which the Advanced Airbag System in your vehi-
cle was certified; For a listing of the child re-
straints that were used to certify your vehicle's
compliance with the U.S. Safety Standard
=> page 280.
— will go out if the front passenger seat is occu-
pied by an adult as registered by the capacitive
passenger detection system.
— The PASSENGER AIR BAG OFF light must come
on and stay on if the ignition is on and...
—a car bed has been installed on the front pas-
senger seat, or
—arearward-facing child restraint has been in-
stalled on the front passenger seat, or
—a forward-facing child restraint has been instal-
led on the front passenger seat,
—and if the electrical capacitance registered on
the front passenger seat is equal to or less than
the combined capacitance of a typical 1 year-
old infant and one of the rearward-facing or
forward-facing child restraints listed in Federal
Motor Vehicle Safety Standard 208 with which
the Advanced Airbag System in your vehicle was
certified.
If the front passenger seat is not occupied, the
front airbag will not deploy, and the PASSENGER
AIR BAG OFF light will stay on. Never installa
rearward-facing child restraint on the front pas-
senger seat, the safest place for a child in any
kind of child restraint is at one of the seating po-
sitions on the rear seat > page 254, Child re-
266
straints on the front seat - some important
things to know and > page 278, Child safety.
If the PASSENGER AIR BAG light comes
on...
If the PASSENGER AIR BAG OFF light comes on
when one of the conditions listed above is met,
be sure to check the light regularly to make cer-
tain that the PASSENGER AIR BAG OFF light
stays on continuously whenever the ignition is
on. If the PASSENGER AIR BAG OFF light does
not appear on and does not stay on all the time,
stop as soon as it is safe to do so and
— reactivate the system by turning the ignition off
for more than 4 seconds and then turning it on
again;
— remove and reinstall the child restraint. Make
sure that the child restraint is properly installed
and that the safety belt for the front passenger
seat has been correctly routed through the
child restraint as described in the child restraint
manufacturer's instructions;
— make sure that the convertible locking retractor
on the safety belt for the front passenger seat
has been activated and that the safety belt has
been pulled tight.
— make sure that no electrical device (such as a
laptop, CD player, electronic games device,
power inverter or seat heater for child seats) is
placed or used on the front passenger seat if
the device is connected to the 12-volt socket or
the cigarette lighter socket;
— make sure that no seat heater has been retrofit-
ted or otherwise added to the front passenger
seat;
— make sure that nothing can interfere with the
safety belt buckles and that they are not ob-
structed;
— make sure that there are no wet objects (such
as a wet towel) and no water or other liquids on
the front passenger seat cushion.
If the PASSENGER AIR BAG light still does
not come on...
If the PASSENGER AIR BAG OFF light still does
not come on and does not stay on continuously
(when the ignition is switched on),

8V2012721BK
Child safety


ZA\ WARNING
Children on the front seat of any car even with
Advanced Airbags can be seriously injured or
even killed when an airbag inflates. A child in
a rearward-facing child safety seat installed
on the front passenger seat will be seriously
injured and can be killed if the front airbag in-
flates.
— The inflating airbag will hit the child safety
seat or infant carrier with great force and
will smash the child safety seat and child
against the backrest, center armrest, or
door.
— Always install rear-facing child safety seats
on the rear seat.
— If you must install a rearward facing child
safety seat on the front passenger seat in
exceptional circumstances and the PASSEN-
GER AIR BAG OFF light does not come on
and stay on, immediately install the rear-
facing child safety seat in a rear seating po-
sition and have the airbag system inspected
immediately by your Audi dealer.



ZA WARNING
— Forward-facing child seats installed on the
front passenger seat may interfere with the
deployment of the airbag and cause serious
personal injury to the child.
— If exceptional circumstances require the use
of a forward-facing child restraint on the
front passenger's seat, the child's safety and
well-being require the following special pre-
cautions to be taken:
— Always make sure that the forward-facing
seat has been designed and certified by its
manufacturer for use on a front passenger
seat with a front and side airbag.
— Always carefully follow the manufacturer's
instructions provided with the child seat or
infant carrier.
— Never install a child restraint without a
properly attached top tether strap if the
child restraint manufacturer's instructions
require the top tether strap to be used.


— Never put the forward-facing child re-
straint up against or very near the instru-
ment panel.
— Applies to: vehicles with safety belt height
adjustment: Always set the safety belt up-
per anchorage to the adjustment position
that permits proper installation in accord-
ance with the child restraint manufactur-
er's instructions.
— Always move the front passenger seat to
the highest position in the up and down
adjustment range and move it back to the
rearmost position in the seat's fore and aft
adjustment range, as far away from the
airbag as possible, before installing the
forward-facing child restraint.
— Always make sure that the safety belt up-
per anchorage is behind the child restraint
and not next to or in front of the child re-
straint so that the safety belt will be prop-
erly positioned.
— Always make sure that nothing prevents
the front passenger's seat from being
moved to the rearmost position in its fore
and aft adjustment range.
— Never place objects on the seat (such as a
laptop, CD player, electronic games device,
power inverter or seat heater for child
seats). These may influence the electrical
capacitance measured by the capacitive
passenger detection system and can also
fly around in an accident and cause serious
personal injury.
— Never place or use any electrical device
(such as a laptop, CD player, electronic
games device, power inverter or seat heat-
er for child seats) on the front passenger
seat if the device is connected to the 12-
volt socket or the cigarette lighter socket.
— Ifa seat heater has been retrofitted or
otherwise added to the front passenger
seat, never install any child restraint sys-
tem on this seat.
— Make sure that there are no wet objects
(such as a wet towel) and no water or oth-
er liquids on the front passenger seat
cushion.

279

8V2012721BK
Child safety



— The child and the passenger can also injure
each other in an accident.
Never install rear-facing child safety seats or
infant carriers on the front passenger seat.
A child will be seriously injured and can be
killed when the passenger airbag inflates -
even with an Advanced Airbag System.
The inflating airbag will hit the child safety
seat or infant carrier with great force and
will smash the child safety seat and child
against the backrest, center armrest, door
or roof.
Always install rear-facing child safety seats
or infant carriers on the rear seat.
Make sure there is enough space in front of
the child in the child seat. If necessary, ad-
just the angle and position of the seat in
front of the child seat.
Forward-facing child safety seats installed
on the front passenger's seat can interfere
with the airbag when it inflates and cause
serious injury to the child. Always install for-
ward-facing child safety seats on the rear
seat.
If exceptional circumstances require the use
of a forward-facing child restraint on the
front passenger's seat, the child's safety and
well-being require that the following special
precautions be taken:
— Make sure the forward-facing seat has
been designed and certified by its manu-
facturer for use on a front seat with a pas-
senger front and side airbag.
— Always carefully follow the manufacturer's
instructions provided with the child safety
seat or carrier.
— Always move the front passenger seat to
the highest position in the up and down
adjustment range and move it back to the
rearmost position in the seat's fore and aft
adjustment range, as far away from the
airbag as possible, before installing the
forward-facing child restraint.
— Always make sure that the safety belt up-
per
anchorage is behind the child restraint
and not next to or in front of the child re-
straint so that the safety belt will be prop-
erly positioned.
— Always make sure that nothing prevents
the front passenger's seat from being
moved to the rearmost position in its fore
and aft adjustment range.
— Always make sure that the backrest is in
the upright position.
— Never place or use any electrical device
(such as a laptop, CD player, electronic
games device, power inverter or seat heat-
er for child seats) on the front passenger
seat if the device is connected to the 12-
volt socket or the cigarette lighter socket.
— If a seat heater has been retrofitted or
otherwise added to the front passenger
seat, never install any child restraint sys-
tem on this seat.
— Make sure that there are no wet objects
(such as a wet towel) and no water or oth-
er liquids on the front passenger seat
cushion.
— Never place objects on the seat (such as a
laptop, CD player, electronic games device,
power inverter or seat heater for child
seats). These may influence the electrical
capacitance measured by the capacitive
passenger detection system and can also
fly around in an accident and cause serious
personal injury.
— Always buckle the child safety seat firmly in
place even if a child is not sitting in it. A
loose child safety seat can fly around during
a sudden stop or ina collision.
— Always read and heed all WARNINGS when-
ever using a child restrained in a vehicle is
being used > page 245, Safety belts,
=> page 253, Airbag system and > page 278,
Child safety.


ZA WARNING
To reduce the risk of serious injury, make sure
that the PASSENGER AIR BAG OFF light
comes on and stays on whenever a child re-
straint is installed on the front passenger seat
and the ignition is switched on.
— Take the child restraint off the front passen-
ger seat and install it properly at one of the
rear seat positions if the PASSENGER AIR
BAG OFF light does not stay on.

283

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Child safety

ride. The front seat is not the safest place for a
child in a forward-facing child seat. It is a very
dangerous place for an infant or a larger child in
a rearward-facing seat.


ZA WARNING
Not using a child safety seat, using the wrong
child safety seat or improperly installing a
child restraint increases the risk of serious
personal injury and death in a crash.
— Never install rear-facing child safety seats or
infant carriers on the front passenger seat -
even with an Advanced Airbag System. A
child will be seriously injured and can be kil-
led when the inflating airbag hits the child
safety seat or infant carrier with great force
and smashes the child safety seat and child
against the backrest, center armrest, door
or roof > page 254, Child restraints on the
front seat - some important things to
know.
— Always install rear-facing child safety seats
or infant carriers on the rear seat.
— Never install a rear-facing child restraint in
the forward-facing direction. Such restraints
are designed for the special needs of infants
and
very small children and cannot protect
them properly if the seat is forward-facing.
— If you must install a rearward facing child
safety seat on the front passenger seat be-
cause of exceptional circumstances and the
PASSENGER AIR BAG OFF light does not
come on and stay on, immediately install
the rear-facing child safety seat in a rear
seating position and have the airbag system
inspected by your Audi dealer.
— Never place or use any electrical device
(such as a laptop, CD player, electronic
games device, power inverter or seat heater
for child seats) on the front passenger seat
if the device is connected to the 12-volt
socket or the cigarette lighter socket.
— If a seat heater has been retrofitted or oth-
erwise added to the front passenger seat,
never install any child restraint system on
this seat.

— Make sure that there are no wet objects
(such as a wet towel) and no water or other
liquids on the front passenger seat cushion.
— Never place objects on the seat (such as a
laptop, CD player, electronic games device,
power inverter or seat heater for child
seats). These may influence the electrical
capacitance measured by the capacitive pas-
senger detection system and can also fly
around in an accident and cause serious per-
sonal injury.
— Always read and heed all WARNINGS when-
ever using a child restrained in a vehicle is
being used > page 245, Safety belts,
=> page 253, Airbag system and > page 278,
Important information.


Convertible child safety seats
Properly used convertible child safety seats can
help protect toddlers and children over age one
who weigh between 20 and 40 lbs. (9 and 18 kg)
in acrash.

B4L-1425


Fig. 228 Schematic overview: installation of the attach-
ments applicable to a LATCH seat


B4L-1426





Fig. 229 Schematic overview: installation of the seat using
the vehicle's safety belt system
» When using the vehicle safety belt to install a
child safety seat, you must first activate the
285
>