2018 Hyundai Sonata Plug-in Hybrid belt

7-7
7
Maintenance
At least twice a year:(i.e., every Spring and Fall)
Check radiator, heater and air condi-
tioning hoses for leaks or damage.
Check windshield washer spray and wiper operation. Clean wiper
blades with 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 hoodhinges.
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.

7
Maintenance
7-9
Normal Maintenance Schedule
The following maintenance services must be performed to ensure good emission control and performance.
Keep receipts for all vehicle emission services to protect your warranty. Where both mileage and time are shown, the
frequency of service is determined by whichever occurs first.
Number of months or driving distance, whichever comes first
Months1224364860728496108120132144156168180
Miles7.51522.53037.54552.56067.575839098105113
Km1224364860728496108120132144156168180
HSG belts *1Inspect every 7,500 miles or 12 months,
and replace every 67,500 miles or 48 months
Engine oil and engine oil filterRRRRRRRRRRRRRRR
Fuel additives *2Add fuel additives every 7,500 miles or 12months
Air cleaner filterIIIRIIIRIIIRIII
Spark plugsReplace every 97,500 miles
Rotate tiresRotate tires every 7,500 miles
Climate control air filterReplace every 15,000 miles or 12 months
Vacuum hoseIIIIIIIIIIIIIII
Engine coolant / Inverter coolantAt first, replace at 120,000 miles or 10 years :
after that, replace every 30,000 miles or 24 months
MAINTENANCE INTERVALS
MAINTENANCE
ITEM
I : Inspect and if necessary, adjust, correct, clean or replace.
R : Replace or change.
*
1: The drive belt should be replaced when cracks occur or tension is reduced excessively.
*2: If TOP TIER Detergent Gasoline is not available, one bottle of additive is recommended. Additives are available from your authorized HYUNDAI dealer along with information on how to use them. Do not mix other additives.

Maintenance
7-12
Maintenance Under Severe Usage Conditions
The following items must be serviced more frequently on cars normally used under severe driving conditions.
Refer to the chart below for the appropriate maintenance intervals.
R : Replace I : Inspect and, after inspection, clean, adjust, repair or replace if neces\
sary
Maintenance itemMaintenance operationMaintenance intervalsDriving condition
HSG (Hybrid Starter&Generator) belt
REvery 30,000 miles (48,000 km) or 24 months
C, D, E, L
IEvery 3,750 miles (6,000 km) or 6 months
Engine oil and filterREvery 3,750 miles (6,000 km) or 6 monthsA, B, C, D, E,
F, G, H, I, K
Air cleaner filterRMore frequentlyC, E
Spark plugsRMore frequentlyB, H
Climate control air filter
(for evaporator and blower unit)RMore frequentlyC, E
Front brake disc/pads, calipersIMore frequentlyC, D, G, H

7-14
Maintenance
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ED
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Engine oil and filter
The engine oil and filter should be
changed at the intervals specified in
the maintenance schedule. If the car
is being driven in severe conditions,
more frequent oil and filter changes
are required.
HSG (Hybrid starter & genera-
tor) belt
The HSG belt should be changed at
the intervals specified in the mainte-
nance schedule.
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.
Fuel lines, fuel hoses and con-
nections
Check the fuel lines, fuel hoses and
connections for leakage and dam-
age. Have an authorized HYUNDAI
dealer replace any damaged or leak-
ing parts immediately.
Vapor hose and fuel filler cap
The vapor hose and fuel filler cap
should be inspected at those inter-
vals 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.

7-22
Maintenance
Changing engine coolant
Have coolant changed by an author-
ized HYUNDAI dealer according to
the Maintenance Schedule at the
beginning of this chapter.
To prevent damage to engine
parts, put a thick towel around the
radiator cap before refilling the
coolant to prevent the coolant
from overflowing into engine
parts, such as the generator.
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.
NOTICE
H HY
Y B
BR
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ID
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T A
A R
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ER
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TO
O R
R
(
( H
H S
SG
G )
)
B
B E
EL
LT
T
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.
WARNING
When the HSG belt is worn out
or damaged, replace the belt.
Otherwise, it may cause engine
overheating or battery dis-
charge.
CAUTIONDo not use engine coolant or
antifreeze in the washer fluid
reservoir.
Engine coolant can severely
obscure visibility when sprayed
on the windshield and may
cause loss of vehicle control
resulting in an accident.
Engine coolant may also cause
damage to paint and body trim.
WARNING

7-42
Maintenance
4. Tire ply composition andmaterial
The number of layers or plies of rub-
ber-coated fabric in the tire. Tire
manufacturers also must indicate the
materials in the tire, which include
steel, nylon, polyester, and others.
The letter "R" means radial ply con-
struction; the letter "D“ means diago-
nal or bias ply construction; and the
letter "B" means belted-bias ply con-
struction.
5. Maximum permissible infla-tion pressure
This number is the greatest amount
of air pressure that should be put in
the tire. Do not exceed the maximum
permissible inflation pressure. Refer
to the Tire and Loading Information
label for recommended inflation
pressure.
6. Maximum load rating
This number indicates the maximum
load in kilograms and pounds that
can be carried by the tire. When
replacing the tires on the vehicle,
always use a tire that has the same
load rating as the factory installed
tire.
7. Uniform tire quality grading
Quality grades can be found where
applicable on the tire sidewall
between tread shoulder and maxi-
mum section width.
For example:
TREAD wear 200
TRACTION AA
TEMPERATURE A
Tread wear
The tread wear grade is a compara-
tive rating based on the wear rate of
the tire when tested under controlled
conditions on a specified govern-
ment test course. For example, a tire
graded 150 would wear one-and-a-
half times (1½) as well on the gov-
ernment course as a tire graded 100.
The relative performance of tires
depends upon the actual conditions
of their use, however, and may
depart significantly from the norm
due to variations in driving habits,
service practices and differences in
road characteristics and climate.
These grades are molded on the
sidewalls of passenger vehicle tires.
The tires available as standard or
optional equipment on your vehicle
may vary with respect to grade.

7-44
Maintenance
Tire terminology and defini-
tions
Air Pressure
The amount of air inside the tire
pressing outward on the tire. Air
pressure is expressed in pounds per
square inch (psi) or kilopascal (kPa).
Accessory Weight
This means the combined weight of
optional accessories. Some exam-
ples of optional accessories are auto-
matic transmission, power seats, and
air conditioning.
Aspect Ratio
The relationship of a tire’s height to
its width.
Belt
A rubber coated layer of cords that is
located between the plies and the
tread. Cords may be made from steel
or other reinforcing materials.
Bead
The tire bead contains steel wires
wrapped by steel cords that hold the
tire onto the rim.
Bias Ply Tire
A pneumatic tire in which the plies
are laid at alternate angles less than
90 degrees to the centerline of the
tread.
Cold Tire Pressure
The amount of air pressure in a tire,
measured in pounds per square inch
(psi) or kilopascals (kPa) before a tire
has built up heat from driving.
Curb Weight
This means the weight of a motor
vehicle with standard and optional
equipment including the maximum
capacity of fuel, oil and coolant, but
without passengers and cargo.
DOT Markings
A code molded into the sidewall of a
tire signifying that the tire is in com-
pliance with the U.S. Department of
Transportation motor vehicle safety
standards. The DOT code includes
the Tire Identification Number (TIN),
an alphanumeric designator which
can also identify the tire manufactur-
er, production plant, brand and date
of production.
GVWR
Gross Vehicle Weight Rating
GAWR FRT
Gross Axle Weight Rating for the
Front Axle.
GAWR RR
Gross Axle Weight Rating for the
Rear axle.

7-48
Maintenance
Radial-ply tires
Radial-ply tires provide improved
tread life, road hazard resistance and
smoother high speed ride. The radi-
al-ply tires used on this vehicle are of
belted construction, and are selected
to complement the ride and handling
characteristics of your vehicle.
Radial-ply tires have the same load
carrying capacity, as bias-ply or bias
belted tires of the same size, and use
the same recommended inflation
pressure. Mixing of radial-ply tires
with bias-ply or bias belted tires is
not recommended. Any combina-
tions of radial-ply and bias-ply or bias
belted tires when used on the same
vehicle will seriously deteriorate
vehicle handling. The best rule to fol-
low is: Identical pairs of radial-ply
tires should always be used as a set
for the front tires and a set for the
rear tires.Longer wearing tires can be more
susceptible to irregular tread wear. It
is very important to follow the tire
rotation interval in this chapter to
achieve the tread life potential of
these tires. Cuts and punctures in
radial-ply tires are repairable only in
the tread area, because of sidewall
flexing. Consult your tire dealer for
radial-ply tire repairs.
Low aspect ratio tires
Low aspect ratio tires, the aspect
ratio is lower than 50, are provided
for sporty looks.
Because low aspect ratio tires are opti-
mized for handling and braking, their
sidewall is a little stiffer than a standard
tire. Also low aspect ratio tires tend to
be wider and consequently have a
greater contact patch with the road
surface. In some instances they may
generate more road noise compared
with standard tires.
Do not mix bias ply and radial
ply tires under any circum-
stances. This may cause unusu-
al handling characteristics that
may cause loss of vehicle con-
trol resulting in an accident.
WARNING