check engine HYUNDAI SONATA HYBRID 2021 Workshop Manual

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

08
8-5
WARNING
Performing maintenance work on a
vehicle can be dangerous. If you lack
sufficient knowledge and experience or
the proper tools and equipment to do
the work, have it done by an authorized
HYUNDAI dealer.
ALWAYS follow these precautions for
performing maintenance work:
• Park your vehicle on level ground,
shift the gear to P (Park), apply
the parking brake, and press the
Engine Start/Stop button to the OFF
position.
• Block the tires (front and back) to
prevent the vehicle from moving.
Remove loose clothing or jewelry
that can become entangled in
moving parts.
• If you must run the engine during
maintenance, do so out doors or in
an area with plenty of ventilation.
• Keep flames, sparks, or smoking
materials away from the battery and
fuel-related parts. The following lists are vehicle checks and
inspections that should be performed
by the owner or an authorized HYUNDAI
dealer at the frequencies indicated to
help ensure safe, dependable operation
of your vehicle.
Any adverse conditions should be
brought to the attention of your dealer as
soon as possible.
These Owner Maintenance vehicle
checks are generally not covered by
warranties and you may be charged for
labor, parts and lubricants used.
Owner Maintenance Schedule
When you stop for fuel:
•
Check the engine oil level.
• Check the coolant level in the engine
coolant reservoir.
• Check the windshield washer fluid
level.
• Check for low or under-inflated tires.
WARNING
Be careful when checking your engine
coolant/inverter coolant level when the
engine is hot. This may result in coolant
being blown out of the opening and
cause serious burns and other injuries.
OWNER MAINTENANCE

Maintenance
8-6
While operating your vehicle:
• Note any changes in the sound of the
exhaust or any smell of exhaust fumes
in the vehicle.
• Check for vibrations in the steering
wheel. Notice if there is any increased
steering effort or looseness in the
steering wheel, or change in its
straight-ahead position.
• Notice if your vehicle constantly turns
slightly or “pulls” to one side when
traveling on smooth, level road.
• When stopping, listen and check for
unusual sounds, pulling to one side,
increased brake pedal travel or “hard-
to-push” brake pedal.
• If any slipping or changes in the
operation of your transmission occurs,
check the transmission fluid level.
• Check the automatic transmission P
(Park) function.
• Check the parking brake.
• Check for fluid leaks under your
vehicle (water dripping from the air
conditioning system during or after
use is normal).
At least monthly:
• Check coolant level in the engine
coolant reservoir.
• Check the operation of all exterior
lights, including the stoplights, turn
signals and hazard warning flashers.
• Check the inflation pressures of all
tires including the spare for tires that
are worn, show uneven wear, or are
damaged.
• Check for loose wheel lug nuts.
At least twice a year: (i.e., every
Spring and Autumn)
• Check radiator, heater and air
conditioning hoses for leaks or
damage.
• Check windshield washer spray and
wiper operation. Clean wiper blades
with a clean cloth dampened with
washer fluid.
• Check headlamp alignment.
• Check muffler, exhaust pipes, shields
and clamps.
• Check the seat belts for wear and
function.
At least once a year:
• Clean body and door drain holes.
• Lubricate door hinges and hood
hinges.
• Lubricate door and hood locks and
latches.
• Lubricate door rubber weather strips.
• Check the air conditioning system.
• Inspect and lubricate automatic
transmission linkage and controls.
• Clean the battery and terminals.
• Check the brake fluid level.

08
8-13
Engine Oil and Filter
The engine oil and filter should be
changed at the intervals specified in the
maintenance schedule. If the vehicle
is being driven in severe conditions,
more frequent oil and filter changes are
required.
HSG (Hybrid Starter & Generator)
Belt
The HSG belt should be changed at the
intervals specified in the maintenance
schedule.
Fuel Lines, Fuel Hoses and
Connections
Check the fuel lines, fuel hoses and
connections for leakage and damage.
Have an authorized HYUNDAI dealer
replace any damaged or leaking parts
immediately.
Fuel Filter
A clogged filter can limit the speed
at which the vehicle may be driven,
damage the emission system and cause
multiple issues such as hard starting. If
an excessive amount of foreign matter
accumulates in the fuel tank, the
filter may require replacement more
frequently. After installing a new filter,
run the engine for several minutes,
and check for leaks at the connections.
Fuel filters should be installed by an
authorized HYUNDAI dealer.
Vapor Hose and Fuel Filler Cap
The vapor hose and fuel filler cap should
be inspected at those intervals specified
in the maintenance schedule. Make sure
a new vapor hose or fuel filler cap is
correctly replaced.
Air Cleaner Filter
A genuine HYUNDAI air cleaner filter
is recommended when the filter is
replaced.
Spark Plugs
Make sure to install new spark plugs of
the correct heat range.
Cooling System
Check cooling system components, such
as radiator, coolant reservoir, hoses and
connections for leakage and damage.
Replace any damaged parts.
Engine Coolant/Inverter Coolant
The coolant should be changed at the
intervals specified in the maintenance
schedule.
Automatic Transmission Fluid
Automatic transmission fluid should
not be checked under normal usage
conditions. But in severe conditions, the
fluid should be changed at an authorized
HYUNDAI dealer in accordance to the
scheduled maintenance at the beginning
of this chapter.
EXPLANATION OF SCHEDULED MAINTENANCE ITEMS

Maintenance
8-14
Information
Automatic transmission fluid color is red
when new.
As the vehicle is driven, the automatic
transmission fluid will begin to look
darker. This is a normal condition and you
should not judge the need to replace the
fluid based upon the changed color.
NOTICE
The use of a non-specified fluid could
result in transmission malfunction
and failure. Use only the specified
automatic transmission fluid (refer
to “Recommended Lubricants and
Capacities” in chapter 2).
Engine Clutch Actuator Fluid
The engine clutch actuator fluid level
should be inspected or replaced to the
intervals specified in the maintenance
schedule.
Brake Hoses and Lines
Visually check for proper installation,
chafing, cracks, deterioration and any
leakage. Replace any deteriorated or
damaged parts immediately.
Brake Fluid
Check the brake fluid level in the brake
fluid reservoir. The level should be
between the MIN and the MAX marks
on the side of the reservoir. Use only
hydraulic brake fluid conforming to DOT
4 specification.
Parking Brake
Inspect the parking brake system.
Brake Discs, Pads, Calipers and
Rotors
Check the pads, the disc, and the rotor
for any excessive wear-out. Inspect
calipers for any fluid leakage
Exhaust Pipe and Muffler
Visually inspect the exhaust pipes,
muffler and hangers for cracks,
deterioration, or damage. Start
the engine and listen carefully for
any exhaust gas leakage. Tighten
connections or replace parts as
necessary.
Suspension Mounting Bolts
Check the suspension connections for
looseness or damage. Retighten to the
specified torque.
Steering Gear Box, Linkage &
Boots/Lower Arm Ball Joint
With the vehicle stopped and the hybrid
system off, check for excessive free-play
in the steering wheel. Check the linkage
for bends or damage. Check the dust
boots and ball joints for deterioration,
cracks, or damage.
Replace any damaged parts.
Drive Shafts and Boots
Check the drive shafts, boots and clamps
for cracks, deterioration, or damage.
Replace any damaged parts and, if
necessary, repack the grease.
Air Conditioning Refrigerant
Check the air conditioning lines and
connections for leakage and damage.

08
8-15
Checking the Engine Oil Level
1. Follow all of the oil manufacturer’s
precautions.
2. Be sure the vehicle is on the level
ground in P (Park) with the parking
brake set and the wheels blocked.
3. Turn the engine on and allow the
engine to reach normal operating
temperature.
4. Turn the engine off and wait about
five minutes for the oil to return to the
oil pan.
5. Pull the dipstick out, wipe it clean, and
re-insert it fully.
ODN8H089002
6. Pull the dipstick out again and check
the level. The level should be between
F (Full) and L (Low).
ODN8H089003
7. If it is near or at L, add enough oil to
bring the level to F.
Use only the specified engine oil (Refer
to “Recommended Lubricants and
Capacities” section in chapter 2).
NOTICE
To prevent damage to your engine:
• Do not overfill with engine oil. Add oil
in small quantities and recheck level
to ensure engine is not overfilled.
• Do not spill engine oil when adding
or changing engine oil. Use a funnel
to help prevent oil from being spilled
on engine components. Wipe off
spilled oil immediately.
ENGINE OIL

Maintenance
8-16
Checking the Engine Oil and
Filter
Have engine oil and filter changed by an authorized HYUNDAI dealer according
to the Maintenance Schedule at the
beginning of this chapter.
WARNING
CALIFORNIA PROPOSITION 65
WARNING
Engine oil contains chemicals known to
the State of California to cause cancer,
birth defects and reproductive harm.
Used engine oil may cause irritation or
cancer of the skin if left in contact with
the skin for prolonged periods of time.
Always protect your skin by washing
your hands thoroughly with soap and
warm water as soon as possible after
handling used oil.

08
8-17
The high-pressure cooling system has a
reservoir filled with year-round antifreeze
coolant. The reservoir is filled at the
factory.
Check the antifreeze protection and
coolant level at least once a year, at
the beginning of the winter season and
before traveling to a colder climate.
Checking the Coolant Level
„„Engine coolant
ODN8H089054L
„„Inverter coolant
ODN8H089053L
Check the condition and connections
of all cooling system hoses and
heater hoses. Replace any swollen or
deteriorated hoses.
The coolant level should be filled
between the MAX and the MIN marks on
the side of the coolant reservoir when
the engine is cool.If the coolant level is low, add the
selected anti-freeze according to the proper coolant mix ratio to bring the level to the MAX mark, but do not overfill. If
frequent additions are required, see an
authorized HYUNDAI dealer for a cooling
system inspection.
„„Engine coolant cap
ODN8H089055
„„Inverter coolant cap
ODN8H089056
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.
ENGINE COOLANT/INVERTER COOLANT

Maintenance
8-18
Turn the vehicle 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
while the pressure is released from
the cooling system. When you are sure
all the pressure has been released,
using a thick towel, continue turning
counterclockwise to remove it.
Information
The engine coolant and/or inverter coolant
level is influenced by the hybrid system
temperature. Before checking or refilling
the engine coolant and/or inverter coolant,
turn the hybrid vehicle off.
WARNING
The electric motor for the cooling fan may continue to
operate or start up when the
engine is not running and can
cause serious injury. Keep
hands, clothing and tools away
from the rotating fan blades of
the cooling fan.
Keep hands, clothing and tools away
from the rotating fan blades of the
cooling fan.
Always turn off the vehicle unless the
vehicle has to be inspected with the
engine on. Be cautious as the cooling
fan may operate if the negative (-)
battery terminal is not disconnected.
WARNING
Make sure the coolant cap is properly
closed after refilling coolant. Otherwise
the engine could be overheated while
driving.
„„Engine compartment front view
OOSH089010L
1. Check if the coolant cap label is
straight In front.
„„Engine compartment rear view
ODN8H089044
2. Make sure that the tiny protrusions
inside the coolant cap is securely
interlocked.

Maintenance
8-20
Checking the Hybrid Starter &
Generator (HSG) Belt
Have the Hybrid Starter & Generator
(HSG) belt inspected or replaced
according to the Maintenance Schedule
in this chapter by an authorized
HYUNDAI dealer.
CAUTION
When the HSG belt is worn out or
damaged, replace the belt.
Otherwise, it may cause engine
overheating or battery discharge.
WARNING
• Turn the vehicle off while you inspect
the engine or Hybrid Starter &
Generator (HSG) belt. Otherwise it
may result in serious injury.
• Keep hands, clothing etc. away from
the Hybrid Starter & Generator (HSG)
belt.
Checking the Brake Fluid Level
ODN8H089005
Check the fluid level in the reservoir
periodically. The fluid level should be
between MAX and MIN marks on the side
of the reservoir.
Before removing the reservoir cap and
adding brake fluid, clean the area around
the reservoir cap thoroughly to prevent
brake fluid contamination.
If the level is low, add the specified brake
fluid to the MAX level. The level will fall
with accumulated mileage. This is a
normal condition associated with the
wear of the brake linings. If the fluid level
is excessively low, have the brake system
checked by an authorized HYUNDAI
dealer.
WARNING
If the brake system requires frequent
additions of fluid this could indicate
a leak in the brake system. Have the
vehicle inspected by an authorized
HYUNDAI dealer.
HYBRID STARTER &
GENERATOR (HSG) BELT BRAKE FLUID