2021 HYUNDAI SONATA HYBRID engine

08
8-57
The emission control system of your
vehicle is covered by a written limited
warranty. Please see the warranty
information contained in the Owner’s
Handbook & Warranty Information
booklet in your vehicle.
Your vehicle is equipped with an
emission control system to meet all
applicable emission regulations. There
are three emission control systems, as
follows.
(1) Crankcase emission control system
(2) Evaporative emission control system
(3) Exhaust emission control system
In order to ensure the proper function
of the emission control systems, it
is recommended that you have your
vehicle inspected and maintained
by an authorized HYUNDAI dealer in
accordance with the maintenance
schedule in this manual.
NOTICE
For the Inspection and Maintenance
Test (with Electronic Stability Control
(ESC) system)
• To prevent the vehicle from misfiring
during dynamometer testing, turn
the Electronic Stability Control
(ESC) system off by pressing the ESC
switch (ESC OFF light illuminated).
• After dynamometer testing is
completed, turn the ESC system back
on by pressing the ESC switch again.
1. Crankcase Emission Control
System
The positive crankcase ventilation system
is employed to prevent air pollution
caused by blow-by gases being emitted
from the crankcase. This system supplies
fresh filtered air to the crankcase through
the air intake hose. Inside the crankcase,
the fresh air mixes with blow-by gases,
which then pass through the PCV valve
into the induction system.
2. Evaporative Emission Control
System Including Onboard
Refueling Vapor Recovery
(ORVR)
The Evaporative Emission Control System
is designed to prevent fuel vapors from
escaping into the atmosphere. The
ORVR system is designed to allow the
vapors from the fuel tank to be loaded
into a canister while refueling at the gas
station, preventing the escape of fuel
vapors into the atmosphere.
Canister
Fuel vapors generated inside the fuel
tank are absorbed and stored in the
onboard canister. When the engine is
running, the fuel vapors absorbed in the
canister are drawn into the surge tank
through the purge control solenoid valve.
Purge Control Solenoid Valve (PCSV)
The purge control solenoid valve
is controlled by the Engine Control
Module (ECM); when the engine coolant
temperature is low during idling, the
PCSV closes so that evaporated fuel
is not taken into the engine. After the
engine warms-up during ordinary
driving, the PCSV opens to introduce
evaporated fuel to the engine.
EMISSION CONTROL SYSTEM

Maintenance
8-58
3. Exhaust Emission Control
System
The Exhaust Emission Control System is
a highly effective system which controls
exhaust emissions while maintaining
good vehicle performance.
When the engine starts or fails to start,
excessive attempts to restart the engine
may cause damage to the emission
system.
Engine exhaust (carbon monoxide)
precautions
• Carbon monoxide can be present
with other exhaust fumes. If you smell
exhaust fumes of any kind in your
vehicle, drive with all the windows
fully open. Have your vehicle checked
and repaired immediately.
WARNING
Engine exhaust gases contain carbon
monoxide (CO). Though colorless and
odorless, it is dangerous and could be
lethal if inhaled. Follow the instructions
on this page to avoid CO poisoning.
WARNING
CALIFORNIA PROPOSITION 65
WARNING
Engine exhaust and a wide variety of
automobile components and parts,
including components found in the
interior furnishings in a vehicle, contain
or emit chemicals known to the State
of California to cause cancer and
birth defects and reproductive harm.
In addition, certain fluids contained
in vehicles and certain products of
component wear contain or emit
chemicals known to the State of
California to cause cancer and birth
defects or other reproductive harm.
• Do not operate the engine in confined
or closed areas (such as garages) any
more than what is necessary to move
the vehicle in or out of the area.
• When the vehicle is stopped in an
open area for more than a short time
with the engine running, adjust the
ventilation system (as needed) to draw
outside air into the vehicle.
• Never sit in a parked or stopped
vehicle for any extended time with the
engine running.
• When the engine stalls or fails to
start, excessive attempts to restart
the engine may cause damage to the
emission control system.

08
8-59
Operating precautions for catalytic
converters (if equipped)
WARNING
The exhaust system and catalytic
converter are very hot during and
immediately after the engine has been
running. To avoid SERIOUS INJURY or
DEATH:
• Do not park, idle, or drive the vehicle
over or near flammable objects, such
as grass, vegetation, paper, leaves,
etc. A hot exhaust system can ignite
flammable items under your vehicle.
• Keep away from the exhaust system
and catalytic converter or you may
get burned.
Also, do not remove the heat sink
around the exhaust system, do not
seal the bottom of the vehicle, and
do not coat the vehicle for corrosion
control. It may present a fire risk
under certain conditions. Your vehicle is equipped with a catalytic
converter emission control device.
To prevent damage to the catalytic
converter and to your vehicle, take the
following precautions:
•
Use only UNLEADED FUEL for
gasoline engines.
• Do not operate the vehicle when
there are signs of engine malfunction,
such as misfire or a noticeable loss of
performance.
• Do not misuse or abuse the engine.
Examples of misuse are coasting with
the engine off and descending steep
grades in gear with the engine off.
• Do not operate the engine at high
idle speed for extended periods (5
minutes or more).
• Do not modify or tamper with any
part of the engine or emission
control system. All inspections and
adjustments must be made by an
authorized HYUNDAI dealer.
• Avoid driving with extremely low
fuel level. If you run out of gasoline,
it could cause the engine to misfire
and result in excessive loading of the
catalytic converter.

Index
I-6
E
Electric Power Steering (EPS)
........................................................................\
....5-38
Electronic Stability Control (ESC)
.....................................................................6-28
Emergency towing
........................................................................\
......................7-28
Emergency trunk safety release
........................................................................\
..5-64
Emission control system
........................................................................\
.............8-57
Crankcase emission control system
...............................................................8-57
Evaporative emission control System
............................................................8-57
Exhaust emission control system
...................................................................8-58
Energy flow
........................................................................\
.................................1-20
Engine only propulsion
........................................................................\
..........1-20
EV propulsion
........................................................................\
........................1-20
Power assist
........................................................................\
.............................1-20
Vehicle stop
........................................................................\
............................1-20
Engine brake ........................................................................\
............................ 1-21
Engine generation ........................................................................\
.................... 1-21
Power reserve
........................................................................\
..........................1-21
Regeneration
........................................................................\
..........................1-21
Engine brake/regeneration
........................................................................\
.....1-22
Engine generation/motor drive
........................................................................\
1-22
Engine generation/regeneration
.....................................................................1-22
Start engine to avoid battery discharge
..........................................................1-22
Engine compartment
........................................................................\
.....................2-6
Engine compartment panel fuse replacement
.....................................................8-40
Engine coolant
........................................................................\
............................8-17
Engine number
........................................................................\
............................2-14
Engine oil
........................................................................\
....................................8-15
Engine specification ........................................................................\
....................... 2-7
Engine Start/Stop button
........................................................................\
................6-6
Event Data Recorder (EDR)
........................................................................\
..........1-8
Explanation of scheduled maintenance items
.....................................................8-13

I
I -7
Exterior features........................................................................\
........................... 5-62
Hood
........................................................................\
.......................................5-62
Trunk
........................................................................\
......................................5-63
Emergency trunk safety release ....................................................................... 5-64
Fuel Filler Door
........................................................................\
......................5-68
Exterior overview
........................................................................\
..........................2-2
Front view
........................................................................\
................................2-2
Rear view
........................................................................\
.................................2-3
F
Flat tire
........................................................................\
........................................7-14
Changing spare tire
........................................................................\
.....................7-15
Floor mat anchor(s) ........................................................................\
.................... 5-125
Fluid
........................................................................\
...................................................-
Brake fluid
........................................................................\
..............................8-20
Washer fluid
........................................................................\
...........................8-21
Forward Collision-Avoidance Assist (FCA)
.......................................................6-38
Junction Turning ........................................................................\
...................... 6-53
Forward/Reverse Parking Distance Warning (PDW)
.........................................5-91
Front seat adjustment
........................................................................\
....................3-5
Manual adjustment
........................................................................\
...................3-5
Power adjustment
........................................................................\
.....................3-7
Reclining seatback
........................................................................\
...................3-8
Front seat head restraints
........................................................................\
.............3-12
Adjusting the height up and down
.................................................................3-12
Removal/Reinstallation
........................................................................\
..........3-13
Fuel Filler Door
........................................................................\
..........................5-69
Fuel gauge
........................................................................\
.....................................4-4
Fuel requirements
........................................................................\
..........................1-5
Fuel additives
........................................................................\
...........................1-6
Fuses
........................................................................\
...........................................8-38
Instrument panel fuse replacement .................................................................. 8-39
Engine compartment panel fuse replacement
................................................8-40
Fuse/relay panel description
........................................................................\
...8-41

I
I-9
I
If the 12 volt battery is discharged
........................................................................\
7-4
If the engine overheats
........................................................................\
..................7-7
If the engine stalls at a crossroad or crossing
........................................................7-2
If the engine stalls while driving
........................................................................\
..7-2
If the engine will not start
........................................................................\
.............7-3
If you have a flat tire while driving
......................................................................7-3
Ignition switch
........................................................................\
..............................6-6
Engine Start/Stop button
........................................................................\
..........6-6
Remote start
........................................................................\
.............................6-9
Immobilizer system
........................................................................\
....................5-11
Important safety precautions ........................................................................\
.......... 3-2
Always wear your seat belt
........................................................................\
......3-2
Restrain all children
........................................................................\
.................3-2
Air bag hazards
........................................................................\
........................3-2
Driver distraction
........................................................................\
.....................3-2
Control your speed
........................................................................\
...................3-2
Keep your vehicle in safe condition
.................................................................3-2
In case of an emergency while driving
.................................................................7-2
Infotainment system ........................................................................\
................... 5-126
USB and iPod® port
........................................................................\
............5-126
Antenna
........................................................................\
................................5-126
Steering wheel audio controls
......................................................................5-127
Bluetooth® Wireless Technology hands-free ...............................................5-128
Audio / Video / Navigation system
..............................................................5-128
Blue Link® center
........................................................................\
................5-128
Inside rearview mirror
........................................................................\
................5-42
Instrument cluster
........................................................................\
.........................4-4
Adjusting instrument cluster illumination
........................................................4-5
Gauges and meters
........................................................................\
...................4-5
Transmission shift indicator
........................................................................\
.....4-9
Warning and indicator lights
........................................................................\
..4-10
LCD display messages
........................................................................\
...........4-19
LCD display (Type A, B)
........................................................................\
.......4-26
LCD display (Type C)
........................................................................\
............4-39

I
I-11
LCD display (Type C) ........................................................................\
................4-39
LCD display control
........................................................................\
...............4-39
View modes
........................................................................\
............................4-40
Utility view mode
........................................................................\
...................4-41
Option menu
........................................................................\
...........................4-43
User settings mode
........................................................................\
.................4-44
LCD display messages
........................................................................\
................4-19
Shift to P to start engine
........................................................................\
..........4-19
Shift to P
........................................................................\
.................................4-19
Low key battery ........................................................................\
....................... 4-19
Press brake pedal to start engine
....................................................................4-19
Key not in vehicle
........................................................................\
..................4-19
Key not detected
........................................................................\
.....................4-19
Press START button again
........................................................................\
.....4-19
12V bettery discharging due to additional electrical devices
..........................4-19
Press START button with key
........................................................................\
4-20
Check BRAKE SWITCH fuse
.......................................................................4-20
Door, Hood, Trunk open indicator
.................................................................4-20
Sunroof open indicator
........................................................................\
...........4-20
Press START button while turning wheel
.......................................................4-20
Check steering wheel lock system
..................................................................4-20
Lights mode
........................................................................\
............................4-21
Wiper mode
........................................................................\
............................4-21
Low pressure
........................................................................\
..........................4-21
Low washer fluid ........................................................................\
..................... 4-21
Low fuel
........................................................................\
..................................4-21
Engine has overheated ........................................................................\
............. 4-21
Check exhaust system
........................................................................\
.............4-22
Check headlight
........................................................................\
.......................4-22
Check turn signal ........................................................................\
..................... 4-22
Check brake light
........................................................................\
....................4-22
Check headlamp LED
........................................................................\
.............4-22
Check Active Air Flap system
........................................................................\
.4-22

Index
I-12
Ready to start driving ........................................................................\
.....1-17, 4-22
Check regenerative brakes
.....................................................................1-17, 4-22
Stop vehicle and check brakes
...............................................................1-17, 4-22
Check Hybrid system
........................................................................\
.....1-17, 4-23
Stop safely and check Hybrid system
....................................................1-18, 4-23
Check Hybrid system. Do not start engine ......................................................4-23
Stop safely and check power supply
......................................................1-18, 4-23
Check virtual engine sound system
........................................................1-18, 4-23
Refuel to prevent Hybrid battery damage
..............................................1-19, 4-23
Refill inverter coolant
........................................................................\
....1-19, 4-23
Park with engine On to charge battery
...................................................1-19, 4-23
Start engine to avoid battery discharge
..................................................1-19, 4-23
LCD display modes
........................................................................\
....................4-25
Trip computer mode
........................................................................\
...............4-26
Turn By Turn (TBT) mode
........................................................................\
.....4-26
Driving assist mode
........................................................................\
................4-26
Master warning mode
........................................................................\
.............4-27
User settings mode
........................................................................\
.................4-27
Light
........................................................................\
............................................5-72
AUTO headlamp position
........................................................................\
......5-72
Daytime running light (DRL) ........................................................................\
.. 5-72
Parking lamp position
........................................................................\
............5-73
Headlamp position
........................................................................\
.................5-73
High beam operation
........................................................................\
..............5-73
High Beam Assist (HBA)
........................................................................\
.......5-74
Turn signals
........................................................................\
............................5-77
Lane change signals
........................................................................\
...............5-77
Battery saver function
........................................................................\
............5-77
Headlamp delay function
........................................................................\
.......5-77
Headlamp leveling device
........................................................................\
......5-78
Light bulbs
........................................................................\
..................................8-43
Lubricants and capacities
........................................................................\
............2-11
Luggage compartment lamp
........................................................................\
.......5-80