2021 HYUNDAI SONATA HYBRID engine

01
1-23
SAFETY PRECAUTIONS FOR HYBRID SYSTEM
Hybrid Vehicle Components
High voltage battery system
„„HPCU (Hybrid Power Control Unit) *1
ODN8HQ019029
„„High voltage battery system *2
OAEQ046019
*1 : Located in the engine compartment
*2 : Located under the rear seats
WARNING
Never touch orange colored or high
voltage labeled components, including
wires, cables, and connections. When
the insulators or covers are damaged or
removed, severe injury or death from
electrocution may occur.
WARNING
While replacing the fuses in the
engine compartment, never touch the
HPCU. The HPCU carries high voltage.
Touching the HPCU may result in
electrocution, serious injury, or death.
WARNING
In the hybrid system, the hybrid battery
uses high voltage to operate the motor
and other components. This high
voltage hybrid battery system can be
very dangerous.
Never touch the hybrid system. When
you touch the hybrid battery system,
serious injury or death may occur.
CAUTION
• Do not pile up any items in an area
behind the high voltage battery. In
a crash, the battery may become
unstable, or its performance may
degrade.
• Do not apply strong force nor pile
up any items above the luggage
compartment. Such an attempt
may distort the high voltage battery
case, causing a safety problem or
degrading the performance.
• Be careful when loading flammable
liquid in the luggage compartment.
It could cause operational and safety
degradation if the liquid leaks and
flows in the high voltage battery.
„„Drive motor *3
OAEQ046017
*3 : Located in the engine compartment

01
1-25
NOTICE
• When the vehicle is paint baked, do
not bake over 30 minutes in 158°F
(70°C) or 20 minutes in 176°F (80°C)
degree.
• Do not wash the engine
compartment, using water. Water
may cause an electric shock and
damage the electronic components.
WARNING
This hybrid vehicle uses the hybrid
battery system inverter and converter
to generate high voltage. High voltage
in the hybrid battery system is very
dangerous and may cause severe burns
and electric shock. This may result in
serious injury or death.
• For your safety, never touch,
replace, disassemble or remove the
hybrid battery system including
components, cables and connectors.
Severe burns or electric shock may
result in serious injury or death when
you fail to follow this warning.
• When the hybrid battery system
operates, the hybrid battery system
can be hot. Always be careful
because burns or electric shock may
be caused by high voltage.
• Do not spill liquid on the HPCU, HSG,
motor and fuses. If the hybrid system
components come in contact with
liquid, it may result in electric shock.
Service Interlock Connector
ODN8HQ019032
In case of emergency, cut the service
interlock connector cable to isolate the
high voltage of the battery.
WARNING
Never disconnect the service interlock
connector or cut the wire except in an
emergency situation.
Serious problems may occur, such as
the vehicle will not start.
Hybrid Battery Cooling Duct
ODN8HQ019027
The hybrid battery cooling duct is
located on the left side of the rear seats.
The cooling duct cools down the hybrid
battery. When the hybrid battery cooling
duct is blocked, the hybrid battery may
be overheated.
Clean the cooling duct for the hybrid
battery with a dry cloth on a regular
basis.

2
2. Vehicle Information
Vehicle Information
Exterior Overview ........................................................................\
......................2-2
Interior Overview
........................................................................\
......................2-4
Instrument Panel Overview
........................................................................\
......2-5
Engine Compartment
........................................................................\
...............2-6
Dimensions
........................................................................\
.................................2-7
Engine specification
........................................................................\
..................2-7
Bulb Wattage
........................................................................\
.............................2-8
Tires and Wheels
........................................................................\
.......................2-9
Volume and Weight
........................................................................\
.................2-10
Air Conditioning System
........................................................................\
..........2-10
Recommended Lubricants and Capacities
.....................................................2-11Recommended SAE Viscosity Number .....................................................................2-12
Vehicle Identification Number (vin) ................................................................2-13
Vehicle Certification Label
........................................................................\
......2-13
Tire Specification and Pressure Label
............................................................2-14
Engine Number
........................................................................\
........................2-14

2-5
02
The actual shape may differ from the illustration.ODN8H019004
1. Instrument cluster ..................................4-4
2. Driver’s front air bag .............................3-39
3. Engine Start/Stop button .......................6-6
4. Audio / Video / Navigation system.....5-128
5. Hazard warning flasher switch ...............7-2
6. Automatic climate control system .....5-101
7. Passenger’s front air bag .....................3-39
8. Glove box ..............................................5-118
9. Transmission shift button .....................6-10
10. Parking Distance Warning Off button ...5-87
Parking Safety button
............................5-91
11. Parking/View button ............................5-86
12. Drive mode integrated control system ...6-33
13. AUTO HOLD ..........................................6-24
INSTRUMENT PANEL OVERVIEW

2-6
Vehicle Information
„„Smartstream G2.0 GDi HEV
The actual engine room in the vehicle may differ from the illustration.ODN8H089001
ENGINE COMPARTMENT
1. Engine coolant reservoir .......................8-17
2. Engine coolant reservoir cap ................8-17
3. Inverter coolant reservoir......................8-17
4. Brake fluid reservoir .............................8-20
5. Air cleaner .............................................8-22
6. Engine oil dipstick .................................8-15
7. Engine oil filler cap ................................8-15
8. Windshield washer fluid reservoir ........8-21
9. Fuse box ................................................8-42

02
2-7
DIMENSIONS
Itemsin. (mm)
Overall length 192.9 (4,900)
Overall width 73.2 (1,860)
Overall height 56.9 (1,445)
Front tread 205/65 R16
64.3 (1,633)
215/55 R17 63.9 (1,623)
Rear tread 205/65 R16
64.6 (1,640)
215/55 R17 64.2 (1,630)
Wheelbase 111.8 (2,840)
ENGINE SPECIFICATION
EngineDisplacement
cc (cu. in) Bore x Stroke
mm (in.) Firing order
No. of cylinders
Smartstream G2.0 GDi HEV 1,999 (121.98) 81 x 97
(3.18 x 3.82) 1-3-4-2
In-line 4 cylinder

02
2-11
RECOMMENDED LUBRICANTS AND CAPACITIES
To help achieve proper engine and powertrain performance and durability, use only
lubricants of the proper quality. The correct lubricants also help promote engine
efficiency that results in improved fuel economy.
These lubricants and fluids are recommended for use in your vehicle.
LubricantVolumeClassification
Engine oil
*1 *2 (drain and
refill)
4.5 US qt. (4.3 ℓ)API Lastest (SN PLUS) *3
Automatic transmission fluid6.3 US qt. (6.0 ℓ)
MICHANG ATF SP-IV, SK ATF SP IV,
NOCA ATF SP-IV, S-oil ATF SP-IV
HYUNDAI genuine ATF SP-IV
or other brands meeting the
above specification approved by
HYUNDAI Motor Co.
Coolant
8.6 US qt. (8.18 ℓ)Mixture of antifreeze and distilled
water (Ethylene glycol with
phosphate based coolant)
Brake fluid
*4required amount DOT-4
Fuel
13.2 gal. (50 ℓ)Refer to “Fuel requirements” in
chapter 1.
*1 : Refer to the recommended SAE viscosity numbers on page 12.
*2 : Engine oils labeled Energy Conserving Oil are now available. Along with other additional
benefits, they contribute to fuel economy by reducing the amount of fuel necessary
to overcome engine friction. Often, these improvements are difficult to measure in
everyday driving, but in a year’s time, they can offer significant cost and energy savings.
*3 : If the recommended engine oil is not available in your country, you are able to use API
SL/ILSAC GF-3 or ACEA A3.
*4 : To maintain the best braking performance and ABS/ESC performance, we recommend
that you use genuine brake fluid that conform to specifications. (Standard : SAE J1704
DOT-4 LV, ISO4925 CLASS-6 and FMVSS 116 DOT-4)

Vehicle Information
2-12
Recommended SAE Viscosity
Number
CAUTION
Always be sure to clean the area around
any filler plug, drain plug, or dipstick
before checking or draining any
lubricant. This is especially important
in dusty or sandy areas and when the
vehicle is used on unpaved roads.
Cleaning the plug and dipstick areas
will prevent dirt and grit from entering
the engine and other mechanisms that
could be damaged.Engine oil viscosity (thickness) has an
effect on fuel economy and cold weather
operating (engine start and engine oil
flowability). Lower viscosity engine oils
can provide better fuel economy and
cold weather performance, however,
higher viscosity engine oils are required
for satisfactory lubrication in hot
weather.
Using oils of any viscosity other than
those recommended could result in
engine damage.
When choosing an oil, consider the
range of temperature your vehicle will be
operated in before the next oil change.
Proceed to select the recommended oil
viscosity from the chart.
Temperature Range for SAE Viscosity Numbers
Temperature °C
-30 -20-10 010 20 30 4050
(°F) -10020 40 60 80 100120
Smartstream G2.0 GDi HEV
20W-50
15W-40
10W-30
0W-16, 0/5W-20, 0/5W-30
*1 : For better fuel economy, it is recommended to use the engine oil of a viscosity grade
0W-16 (API LATEST). However, if the engine oil is not available in your country, select the
proper engine oil using the engine oil viscosity chart.
An engine oil displaying this American Petroleum Institute(API) Certification Mark conforms to the International Lubricant
Specification Advisory Committee (ILSAC). It is recommended to
only use engine oils that uphold this API Certification Mark.