2021 HYUNDAI SONATA HYBRID engine

Emergency situations
7-8
WARNING
Never remove the engine coolant cap and/or inverter
coolant cap or the drain plug
while the engine and radiator
are hot.
Hot coolant and steam may blow out
under pressure, causing serious injury.
Turn the hybrid system off and wait until
the engine cools down. Use extreme
care when removing the engine coolant
cap and/or inverter coolant cap. Wrap
a thick towel around it, and turn it
counterclockwise slowly to the first
stop. Step back while the pressure is
released from the cooling system. When
you are sure all the pressure has been
released, press down on the cap, using
a thick towel, and continue turning
counterclockwise to remove it.
CAUTION
• Serious loss of coolant indicates a
leak in the cooling system and should
be checked as soon as possible by an
authorized HYUNDAI dealer.
• When the engine overheats from
low engine coolant, suddenly adding
engine coolant may cause cracks
in the engine. To prevent damage,
add engine coolant slowly in small
quantities.

Emergency situations
7-10
Tire Pressure Monitoring System
WARNING
Over-inflation or under-inflation can
reduce tire life, adversely affect vehicle
handling, and lead to sudden tire failure
that may cause loss of vehicle control
resulting in an accident.
Each tire, including the spare (if
provided), should be checked monthly
when cold and inflated to the inflation
pressure recommended by the vehicle
manufacturer on the vehicle placard
or tire inflation pressure label. (If your
vehicle has tires of a different size than
the size indicated on the vehicle placard
or tire inflation pressure label, you should
determine the proper tire inflation
pressure for those tires.)
As an added safety feature, your
vehicle has been equipped with a tire
pressure monitoring system (TPMS)
that illuminates a low tire pressure
telltale when one or more of your tires is
significantly under-inflated. Accordingly,
when the low tire pressure telltale
illuminates, you should stop and check
your tires as soon as possible, and inflate
them to the proper pressure. Driving on
a significantly under-inflated tire causes
the tire to overheat and can lead to tire
failure.
Under-inflation also reduces fuel
efficiency and tire tread life, and may
affect the vehicle’s handling and
stopping ability.
Please note that the TPMS is not a
substitute for proper tire maintenance,
and it is the driver’s responsibility to
maintain correct tire pressure, even if
under-inflation has not reached the level
to trigger illumination of the TPMS low
tire pressure telltale.
Your vehicle has also been equipped with
a TPMS malfunction indicator to indicate
when the system is not operating
properly. The TPMS malfunction
indicator is combined with the low
tire pressure telltale. When the system
detects a malfunction, the telltale will
flash for approximately one minute and
then remain continuously illuminated.
This sequence will continue upon
subsequent vehicle start-ups as long as
the malfunction exists.
When the malfunction indicator is
illuminated, the system may not be able
to detect or signal low tire pressure as
intended. TPMS malfunctions may occur
for a variety of reasons, including the
installation of replacement or alternate
tires or wheels on the vehicle that
prevent the TPMS from functioning
properly.
Always check the TPMS malfunction
telltale after replacing one or more tires
or wheels on your vehicle to ensure that
the replacement or alternate tires and
wheels allow the TPMS to continue to
function properly.
NOTICE
If any of the below happens, have
the system checked by an authorized
HYUNDAI dealer.
1. The Low Tire Pressure Telltale/TPMS
Malfunction Indicator does not
illuminate for 3 seconds when the
Engine Start/Stop button is pressed
to the ON position or the vehicle is in
the ready (
) mode.
2. The TPMS Malfunction Indicator
remains illuminated after blinking for
approximately 1 minute.
3. The Low Tire Pressure Position
Telltale remains illuminated.

07
7-15
Changing Tires
WARNING
A vehicle can slip or roll off of a jack
causing serious injury or death to you or
those nearby. Take the following safety
precautions:
• Do not get under a vehicle that is
supported by a jack.
• NEVER attempt to change a tire in
the lane of traffic. ALWAYS move the
vehicle completely off the road on
level, firm ground away from traffic
before trying to change a tire. If you
cannot find a level, firm place off
the road, call a towing service for
assistance.
• Be sure to use the jack provided with
the vehicle.
• ALWAYS place the jack on the
designated jacking positions on the
vehicle and NEVER on the bumpers
or any other part of the vehicle for
jacking support.
• Do not start or run the engine while
the vehicle is on the jack.
• Do not allow anyone to remain in the
vehicle while it is on the jack.
• Keep children away from the road
and the vehicle. Follow these steps to change your
vehicle’s tire:
1. Park on a level, firm surface.
2. Shift the gear to P (Park), apply the
parking brake, and press the Engine
Start/Stop button to the OFF position.
3. Press the hazard warning flasher
button.
4. Remove the wheel lug nut wrench,
jack, jack handle, and spare tire from
the vehicle.
ODN8H060089N[A] : Block
5. Block both the front and rear of the
tire diagonally opposite of the tire you
are changing.

07
7-19
Jack Label
OHYK065011
The actual Jack label in the vehicle may differ from the illustration.
For more detailed specifications, refer to the label attached to the jack.
1. Model Name
2. Maximum allowable load
3. When using the jack, set your parking brake.
4. When using the jack, stop the engine.
5. Do not get under a vehicle that is supported by a jack.
6. The designated locations under the frame
7. When supporting the vehicle, the base plate of jack must be vertical under the
lifting point.
8. Shift into Reverse gear on vehicles with manual transmission or move the shift lever
to the P position on vehicles with automatic transmission.
9. The jack should be used on firm level ground.
10. Jack manufacture
11. Production date
12. Representative company and address

Emergency situations
7-26
Towing Service
ODN8H079010L[A] : Dollies
If emergency towing is necessary,
we recommend having it done by
an authorized HYUNDAI dealer or a
commercial tow-truck service.
Proper lifting and towing procedures
are necessary to prevent damage to
the vehicle. The use of wheel dollies or
flatbed is recommended.
It is acceptable to tow the vehicle with
the rear wheels on the ground (without
dollies) and the front wheels off the
ground.
If any of the loaded wheels or suspension
components are damaged or the vehicle
is being towed with the front wheels on
the ground, use a towing dolly under the
front wheels.
When being towed by a commercial tow
truck and wheel dollies are not used,
the front of the vehicle should always be
lifted, not the rear.
CAUTION
ODN8H079012
• Do not tow the vehicle with the front
wheels on the ground as this may
cause damage to the vehicle.
ODN8H079011
• Do not tow with sling-type
equipment. Use wheel lift or flatbed
equipment.
When towing your vehicle in an
emergency without wheel dollies:
1. Release EPB before turning off the
engine.
2. Press the Engine Start/Stop button to
the OFF position.
3. Shift the gear to N (Neutral).
For more details, refer to “Automatic
Transmission” section in chapter 6.
CAUTION
Failure to shift the gear to N (Neutral)
may cause internal damage to the
transmission.
TOWING

8. Maintenance
Engine Compartment ........................................................................\
...............8-3
Maintenance Services
........................................................................\
..............8-4Owner’s Responsibility ........................................................................\
.......................8-4
Owner Maintenance Precautions ........................................................................\
.......8-4
Owner Maintenance ........................................................................\
.................8-5Owner Maintenance Schedule ........................................................................\
............8-5
Scheduled Maintenance Services ....................................................................8 -7Normal Maintenance Schedule ........................................................................\
..........8-8
Maintenance Under Severe Usage Conditions .........................................................8-11
Explanation of Scheduled Maintenance Items ..............................................8-13
Engine Oil
........................................................................\
.................................8-15Checking the Engine Oil Level ........................................................................\
...........8-15
Checking the Engine Oil and Filter ........................................................................\
...8-16
Engine Coolant/Inverter Coolant ....................................................................8-17Checking the Coolant Level ........................................................................\
................ 8-17
Changing Coolant ........................................................................\
..............................8-19
Hybrid Starter & Generator (HSG) Belt ..........................................................8-20Checking the Hybrid Starter & Generator (HSG) Belt .............................................8-20
Brake Fluid ........................................................................\
...............................8-20Checking the Brake Fluid Level ........................................................................\
........8-20
Washer Fluid ........................................................................\
.............................8-21Checking the Washer Fluid Level ........................................................................\
......8-21
Air Cleaner ........................................................................\
...............................8-22Filter Replacement ........................................................................\
.............................8-22
Cabin Air Filter ........................................................................\
.........................8-23Filter Inspection ........................................................................\
.................................. 8-23
Filter Replacement ........................................................................\
.............................8-23
Wiper Blades ........................................................................\
...........................8-24Blade Inspection ........................................................................\
................................8-24
Blade Replacement
........................................................................\
............................8-24
Maintenance
8

Tires and Wheels ........................................................................\
.....................8-25Tire Care ........................................................................\
..............................................8-26
Recommended Cold Tire Inflation Pressures ...........................................................8-26
Check Tire Inflation Pressure ........................................................................\
.............8-27
Tire Rotation ........................................................................\
.......................................8-27
Wheel Alignment and Tire Balance ........................................................................\
...8-28
Tire Replacement ........................................................................\
...............................8-28
Wheel Replacement ........................................................................\
..........................8-30
Tire Traction ........................................................................\
.......................................8-30
Tire Maintenance ........................................................................\
............................... 8-30
Tire Sidewall Labeling
........................................................................\
.......................8-30
Tire Terminology and Definitions ........................................................................\
......8-33
All Season Tires ........................................................................\
..................................8-36
Summer Tires ........................................................................\
....................................8-36
Snow Tires ........................................................................\
.......................................... 8-36
Radial-Ply Tires
........................................................................\
..................................8-36
Low Aspect Ratio Tires ........................................................................\
.......................8-37
Fuses ........................................................................\
........................................8-38Instrument Panel Fuse Replacement .......................................................................8-39
Engine Compartment Panel Fuse Replacement .....................................................8-40
Fuse/Relay Panel Description ........................................................................\
............ 8-41
Light Bulbs ........................................................................\
...............................8-43Headlamp, Parking Lamp, Daytime Running Light,
Turn Signal Lamp and Side Marker Replacement ...................................................8-44
Side Repeater Lamp Replacement ........................................................................\
..8-45
Rear Combination Lamp Replacement ...................................................................8-45
High Mounted Stop Lamp Replacement ..................................................................8-47
License Plate Light Bulb Replacement ....................................................................8-48
Interior Lamp Replacement ........................................................................\
..............8-48
Appearance Care ........................................................................\
....................8-50Exterior Care ........................................................................\
......................................8-50
Interior Care ........................................................................\
.......................................8-54
Emission Control System ........................................................................\
........8-57Crankcase Emission Control System ........................................................................\
8-57
Evaporative Emission Control System Including
Onboard Refueling Vapor Recovery (ORVR)
............................................................8-57
Exhaust Emission Control System ........................................................................\
....8-58
8

8-3
08
„„Smartstream G2.0 GDi HEV
The actual engine compartment in the vehicle may differ from the illustration.
ODN8H089001
1. Engine coolant reservoir
2. Engine coolant reservoir cap
3. Inverter coolant reservoir
4. Brake fluid reservoir
5. Air cleaner
6. Engine oil dipstick
7. Engine oil filler cap
8. Windshield washer fluid reservoir
9. Fuse box
ENGINE COMPARTMENT