Page 257 of 527

05
5-109
Air conditioning
ODN8059121
Push the A/C button to manually turn
the air conditioning system on (indicator
light will illuminate).
Push the button again to turn the air
conditioning system off.
OFF mode
ODN8059123
Push the OFF button of the front to
turn off the air climate control system.
However, you can still operate the mode
and air intake buttons as long as the
ignition switch is in the ON position.
System Operation
Ventilation
1. Select the Face Level mode.
2. Set the air intake control to fresh
mode.
3. Set the temperature control to the
desired position.
4. Set the fan speed control to the
desired speed.
Heating
1. Select the Floor Level mode.
2. Set the air intake control to fresh
mode.
3. Set the temperature control to the
desired position.
4. Set the fan speed control to the
desired speed.
5. If desired, turn the air conditioning ON
with the temperature control knob set
to heat in order to dehumidify the air
before it enters into the cabin.
If the windshield fogs up, select the Floor
& Defrost
mode or press the Front Defrost mode.
Operation Tips
• To keep dust or unpleasant fumes
from entering the car through the
ventilation system, temporarily set the
air intake control to the recirculation
mode. Return the control to the to
Fresh mode when the unpleasant air
outside has diminished. This will help
keep the driver alert and comfortable.
• To help prevent the inside of the
windshield from fogging, set the air
intake control to fresh mode and the
fan speed to the desired position, turn
on the air conditioning system, and
adjust the temperature control to the
desired temperature.
Page 258 of 527

Convenient Features
5-110
Air conditioning
Your HYUNDAI vehicle air conditioning
system is filled with R-1234yf refrigerant.
1. Start the engine.
2. Press the air conditioning button.
3. Set the mode to the Face Level mode.
4. Set the air intake control to
Recirculation mode temporarily to
allow the cabin to cool quickly. When
the desired temperature in the cabin
is reached, change the air intake
control back to Fresh mode.
5. Adjust the fan speed control and
temperature control to maintain
maximum comfort.
When maximum cooling is desired, set
the temperature control to the MAX A/C
position, then set the fan speed control
to the highest setting.
NOTICE
When using the air conditioning system,
monitor the engine temperature gauge
closely while driving up hills or in heavy
traffic when outside temperatures.
Air conditioning system operation
when climbing a steep grade or in
high outside ambient temperatures
can cause engine overheating.
Continue to use the fan, but turn the air
conditioning system off if the engine
temperature gauge indicates engine
overheating. Air conditioning system operation tips
•
If the vehicle has been parked in
direct sunlight during hot weather,
open the windows for a short time
to let the hot air inside the vehicle
escape.
• After sufficient cooling has been
achieved, switch back from the
recirculated air to the fresh outside air
position.
• To help reduce moisture inside of
the windows on rainy or humid
days, decrease the humidity inside
the vehicle by operating the air
conditioning system with the windows
and sunroof closed.
• Use the air conditioning system
every month only for a few minutes
to ensure maximum system
performance.
• If you operate air conditioner
excessively, the difference between
the temperature of the outside air and
that of the windshield could cause
the outer surface of the windshield
to fog up, causing loss of visibility. In
this case, set the mode selection knob
or button to the
position and fan speed control to the lower speed.
Page 259 of 527
![HYUNDAI SONATA HYBRID 2020 Owners Manual 05
5-111
System Maintenance
Cabin air filter
OIK047401L[A] : Outside air, [B] : Recirculated air
[C] : Cabin air filter, [D] : Blower
[E] : Evaporator core, [F] : Heater core
The cabin air filter is i HYUNDAI SONATA HYBRID 2020 Owners Manual 05
5-111
System Maintenance
Cabin air filter
OIK047401L[A] : Outside air, [B] : Recirculated air
[C] : Cabin air filter, [D] : Blower
[E] : Evaporator core, [F] : Heater core
The cabin air filter is i](/manual-img/35/56190/w960_56190-258.png)
05
5-111
System Maintenance
Cabin air filter
OIK047401L[A] : Outside air, [B] : Recirculated air
[C] : Cabin air filter, [D] : Blower
[E] : Evaporator core, [F] : Heater core
The cabin air filter is installed behind
the glove box. It filters the dust or other
pollutants that enter the vehicle through
the heating and air conditioning system.
Have the cabin air filter replaced by an
authorized HYUNDAI dealer according to
the maintenance schedule. If the vehicle
is being driven in severe conditions such
as dusty or rough roads, more frequent
cabin air filter inspections and changes
are required.
If the air flow rate suddenly decreases,
the system should be checked at an
authorized HYUNDAI dealer.
Checking the amount of air
conditioner refrigerant and
compressor lubricant
When the amount of refrigerant is low,
the performance of the air conditioning
is reduced. Overfilling also reduces the
performance of the air conditioning
system.
Therefore, if abnormal operation is
found, have the system inspected by an
authorized HYUNDAI dealer.
NOTICE
It is important that the correct type and
amount of oil and refrigerant is used.
Otherwise, damage to the compressor
and abnormal system operation may
occur. To prevent damage, the air
conditioning system in your vehicle
should only be serviced by trained and
certified technicians. +
Page 260 of 527

Convenient Features
5-112
WARNING
Vehicles equipped with R-1234yf
Since the refrigerant is
mildly flammable and
operated at high pressure,
the air conditioning system
should only be serviced
by trained and certified
technicians. It is important
that the correct type
and amount of oil and
refrigerant are used.
All refrigerants should be reclaimed
with proper equipment.
Venting refrigerants directly to the
atmosphere is harmful to individuals
and environment. Failure to heed these
warnings can lead to serious injuries.
Refrigerant Label (if equipped)
ODN8H070030N
You can find out which air conditioning
refrigerant is applied to your vehicle on
the label located in front of the engine
compartment.
Example
OHYK059002
Each symbols and specification on
the air conditioning refrigerant label is
represented as below:
1. Classification of refrigerant
2. Amount of refrigerant
3. Classification of Compressor lubricant
4. Caution
5. Flammable refrigerant
6. To require registered technician to
service air conditioning system
Page 261 of 527

05
5-113
WINDSHIELD DEFROSTING AND DEFOGGING
WARNING
Windshield heating
Do not use the
or position during cooling operation in extremely
humid weather. The difference between
the temperature of the outside air and
that of the windshield could cause the
outer surface of the windshield to fog
up, causing loss of visibility could cause
an accident resulting in serious injury
or death. In this case, set the mode
selection knob or button to the
position and fan speed control knob or
button to a lower speed.
• For maximum defrost performance,
set the temperature control knob
to the highest temperature setting
(rotated all the way to the right) and
the fan speed control to the highest
setting.
• If warm air to the floor is desired while
defrosting or defogging, set the mode
to the floor-defrost position.
• Before driving, clear all snow and ice
from the windshield, rear window,
side view mirrors, and all side
windows.
• Clear all snow and ice from the
hood and air inlet in the cowl grill
to improve heater and defroster
efficiency and to reduce the
probability of fogging up the inside of
the windshield.
NOTICE
If you start the vehicle when the
weather is cold, more adequate way to
heat the cabin is described below.
1. Turn off or lower the blower, right
after engine starting, because engine
temperature is still low and the air
flow is cold.
2. After few minutes of engine warm
up, turn the blower to low to medium
speed and set the temperature
control to Hot.
To Defog Inside Windshield
ODN8059124
1. Select desired fan speed.
2. Select desired temperature.
3. Press the defroster button ().
4. The air-conditioning will turn on
according to the detected ambient
temperature, fresh mode and
higher fan speed will be selected
automatically.
If the air-conditioning, fresh mode
and higher fan speed are not selected
automatically, adjust the corresponding
button or knob manually.
If the
position is selected, lower fan speed is controlled to higher fan speed.
Page 262 of 527

Convenient Features
5-114
To Defog Outside Windshield
ODN8059127
1. Set fan speed to the highest position.
2. Set temperature to the extreme hot
(HI) position.
3. Press the defroster button ().
4. The air-conditioning will turn on
according to the detected ambient
temperature and fresh mode will be
selected automatically.
If the
position is selected, lower fan speed is controlled to higher fan speed.
Defogging Logic
To reduce the probability of fogging
up the inside of the windshield, the air
intake or air conditioning are controlled
automatically according to certain
conditions such as
or position. To cancel or return the defogging logic,
do the following.
1. Turn the ignition switch to the ON
position.
2. Press the defroster button ().
3. While pressing the air conditioning
button (A/C), press the air intake
control button at least 5 times within
3 seconds.
The automatic climate control
information screen will blink 3 times to
indicate that the defogging logic has
been disabled.
Repeat the steps again to re-enable the
defogging logic.
If the battery has been discharged or
disconnected, it resets to the defog logic
status.
Page 263 of 527

05
5-115
Auto Defogging System (if
equipped)
ODN8059215
Auto defogging helps reduce the
possibility of fogging up the inside of the
windshield by automatically sensing the
moisture on inside the windshield.
The auto defogging system operates
when the heater or air conditioning is on.
0024003800370032
When the Auto Defogging
System operates, the
indicator will illuminate.
If a high amount of humidity is detected
in the vehicle, the Auto Defogging
System will be enabled.
The following steps will be performed
automatically:
Step 1) The A/C button will turn ON.
Step 2) The air in take control will change to Fresh mode under low outside
temperature.
Step 3) The mode will be changed t o defrost to direct airflow to the
windshield.
Step 4) The fan speed will be increased.
To cancel or reset the Auto Defogging
System
Press the front windshield defroster
button for 3 seconds when the ignition
switch is in the ON position.
When the Auto Defogging System is
canceled, defrost button indicator will
blink 3 times.
When the Auto Defogging System is
reset, defrost button indicator will blink 6
times without a signal.
Information
• When the air conditioning is turned
on by Auto defogging system, if you
try to turn off the air conditioning, the
indicator will blink 3 times and the air
conditioning will not be turned off.
• To maintain the effectiveness and
efficiency of the Auto Defogging
System, do not select Recirculation
mode while the system is operating.
• When the Auto Defogging System is
operating, the fan speed adjustment
knob, the temperature adjustment
knob, and the air intake control button
are all disabled.
NOTICE
Do not remove the sensor cover located
on the upper end of the driver side
windshield glass.
Damage to system parts could occur
and may not be covered by your vehicle
warranty.
Page 264 of 527

Convenient Features
5-116
DefrosterNOTICE
To prevent damage to the conductors
bonded to the inside surface of the rear
window, never use sharp instruments or
window cleaners containing abrasives
to clean the window.
Information
If you want to defrost and defog the
front windshield, refer to “Windshield
Defrosting and Defogging” in this chapter.
Rear window defroster
ODN8059283L
The defroster heats the window to
remove frost, fog and thin ice from the
interior and exterior of the rear window,
while engine is running. •
To activate the rear window defroster,
press the rear window defroster
button located in the center facia
switch panel. The indicator on the rear
window defroster button illuminates
when the defroster is ON.
• To turn off the defroster, press the rear
window defroster button again.
Information
• If there is heavy accumulation of snow
on the rear window, brush it off before
operating the rear defroster.
• The rear window defroster
automatically turns off after
approximately 20 minutes or when the
ignition switch is in the LOCK/OFF
position.
Outside mirror defroster
(if equipped)
If your vehicle is equipped with the
outside mirror defrosters, they will
operate at the same time you turn on the
rear window defroster.