2015 Hyundai Sonata Hybrid engine coolant

Maintenance
27
ENGINE COMPARTMENT
OYFH071001
❈The actual engine room in the vehicle may differ from the illustration. 1. Sub relay box
2. Engine coolant reservoir
3. Windshield washer fluid reservoir
4. Radiator cap
5. Engine oil dipstick
6. Engine oil filler cap
7. Brake fluid reservoir
8. Air cleaner
9. Fuse box
10. Inverter coolant
* : if equipped

75
Maintenance
OWNER MAINTENANCE
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 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 coolant level in coolant reser-voirs (engine and inverter).
Check the windshield washer fluid level.
Look for low or under-inflated tires.
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 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 trav-
eling 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 oper- ation of your transaxle occurs, check
the transaxle fluid level.
Check automatic transaxle P (Park) function.
Check parking brake.
Check for fluid leaks under your vehicle (water dripping from the air condition-
ing system during or after use is nor-
mal).
WARNING - Radiator cap &
Inverter coolant cap
Do not remove the radiator cap and
/or inverter coolant cap when the
engine and radiator are hot.
Scalding hot coolant and steam
may blow out under pressure caus-
ing serious injury.

Maintenance
67
At least monthly:
Check coolant level in the enginecoolant reservoir and inverter coolant
reservoir.
Check the operation of all exterior lights, including the stoplights, turn sig-
nals and hazard warning flashers.
Check the inflation pressures of all tires including the spare.
At least twice a year (i.e., every Spring and Fall):
Check radiator, heater, inverter coolant hose and air conditioning hoses for
leaks or damage.
Check windshield washer spray and wiper operation. Clean wiper blades
with clean cloth dampened with wash-
er fluid.
Check headlight alignment.
Check muffler, exhaust pipes, shields and clamps.
Check the lap/shoulder belts for wear and function.
Check for worn tires and loose wheel lug nuts.
At least once a year:
Clean body and door drain holes.
Lubricate door hinges and checks, andhood hinges.
Lubricate door and hood locks and latches.
Lubricate door rubber weatherstrips.
Check the air conditioning system.
Inspect and lubricate automatic transaxle linkage and controls.
Clean battery and terminals.
Check the brake fluid level.
Check the drive belt.

715
Maintenance
NORMAL MAINTENANCE SCHEDULE (CONT.)
120,000 miles (192,000 km) or 96 months
❑Inspect air conditioning refrigerant
❑Inspect brake fluid
❑Inspect brake hoses and lines
❑Inspect drive shafts and boots
❑Inspect exhaust pipe and muffler
❑Inspect front brake disc/pads, calipers
❑Inspect fuel filter *1
❑Inspect fuel lines, fuel hoses and connections
❑Inspect fuel tank air filter (if equipped) *1
❑Inspect parking brake
❑Inspect rear brake disc/pads
❑Inspect steering gear box, linkage & boots/lower arm ball joint,
upper arm ball joint
❑ Inspect suspension mounting bolts
❑Inspect vacuum hose
❑Inspect vapor hose and fuel filler cap
❑Inspect valve clearance *2
(60,000 miles (96,000 km) or 72 months
❑Inspect W/pump belt (auto-tensioner, HSG, w/pump)
(First, 60,000 miles (96,000 km or 72 months
after every 15,000 miles (24,000 km) or 24 months)
❑ Replace air cleaner filter
❑Replace climate control air filter (for evaporator and blower unit)
❑Replace engine coolant (First, 120,000 miles (192,000 km) or 120
months after every 30,000 miles (48,000 km) or 24 months)
❑Replace inverter coolant (First, 120,000 miles (192,000 km) or
120 months after every 30,000 miles (48,000 km) or 24 months)
(Continued)
(Continued)
❑Replace engine oil and filter
(120,000 miles (192,000 km) or 192 months)
❑Add fuel additive *3
(120,000 miles (192,000 km) or 96 months)
❑ Replace HSG belt
(120,000 miles (192,000 km) or 96 months)
❑ Rotate tires
❈ Inspect : Inspect and if necessary, adjust, correct, clean or replace.
*1: Fuel filter & Fuel tank air filter are considered to be maintenance free\
but periodic inspection is recommended for this maintenance schedule depends
on fuel quality. If there are some important safety matters like fuel flow
restriction, surging, loss of power, hard starting problem etc, replace the fuel
filter immediately regardless of maintenance schedule and consult an
authorized HYUNDAI dealer for details.
*
2: Inspect for excessive tappet noise and/or engine vibration and adjust if necessary.
*3: If TOP TIER Detergent Gasoline is not available, one bottle of additive is rec- ommended. Additives are available from your authorized HYUNDAI dealer
along with information on how to use them. Do not mix other additives.
127,500 miles (204,000 km) or 102 months
❑ Inspect air cleaner filter
❑Inspect HSG belt
(127,500 miles (204,000 km) or 204 months)
❑ Inspect vacuum hose
❑Replace engine oil and filter
(127,500 miles (204,000 km) or 204 months)
❑Add fuel additive *3
(127,500 miles (204,000 km) or 204 months)
❑ Rotate tires

717
Maintenance
150,000 miles (240,000 km) or 120 months
❑Inspect air conditioning refrigerant
❑Inspect brake fluid
❑Inspect brake hoses and lines
❑Inspect drive shafts and boots
❑Inspect exhaust pipe and muffler
❑Inspect front brake disc/pads, calipers
❑Inspect fuel filter *1
❑Inspect fuel lines, fuel hoses and connections
❑Inspect fuel tank air filter (if equipped) *1
❑Inspect HSG belt
(150,000 miles (240,000 km) or 240 months)
❑ Inspect parking brake
❑Inspect rear brake disc/pads
❑Inspect steering gear box, linkage & boots/lower arm ball joint,
upper arm ball joint
❑ Inspect suspension mounting bolts
❑Inspect vacuum hose
❑Inspect vapor hose and fuel filler cap
❑Inspect W/pump belt (auto-tensioner, HSG, w/pump)
(First, 60,000 miles (96,000 km or 72 months
after every 15,000 miles (24,000 km) or 24 months)
❑ Replace climate control air filter (for evaporator and blower unit)
❑Replace air cleaner filter
(Continued)
(Continued)
❑Replace engine oil and filter
(150,000 miles (240,000 km) or 240 months)
❑Add fuel additive *3
(150,000 miles (240,000 km) or 120 months)
❑ Replace engine coolant (First, 120,000 miles (192,000 km) or 120
months after every 30,000 miles (48,000 km) or 24 months)
❑Replace inverter engine coolant (First, 120,000 miles (192,000 km)
or 120 months after every 30,000 miles (48,000 km) or 24 months)
❑ Rotate tires
NORMAL MAINTENANCE SCHEDULE (CONT.)
No check, No service required
❑Automatic transaxle fluid
❈ Inspect : Inspect and if necessary, adjust, correct, clean or replace.
*1: Fuel filter & Fuel tank air filter are considered to be maintenance free\
but periodic inspection is recommended for this maintenance schedule depends
on fuel quality. If there are some important safety matters like fuel flow
restriction, surging, loss of power, hard starting problem etc, replace the fuel
filter immediately regardless of maintenance schedule and consult an
authorized HYUNDAI dealer for details.
*
3: If TOP TIER Detergent Gasoline is not available, one bottle of additive is rec- ommended. Additives are available from your authorized HYUNDAI dealer
along with information on how to use them. Do not mix other additives.

Maintenance
20
7
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.
Valve clearance
Inspect excessive valve noise and/or
engine vibration and adjust if necessary.
An authorized HYUNDAI dealer should
perform the operation.
Cooling system
Check cooling system components, such
as radiator, coolant reservoir, hoses and
connections for leakage and damage.
Replace any damaged parts.
Coolant
The engine and inverter coolants should
be changed at the intervals specified in
the maintenance schedule.
Automatic transaxle fluid
Automatic transaxle 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.
✽ ✽
NOTICE
Automatic transaxle fluid color is basi-
cally red.
As the vehicle is driven, the automatic
transaxle 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.
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 brake fluid level in the brake fluid
reservoir. The level should be between
“MIN” and “MAX” marks on the side of
the reservoir. Use only hydraulic brake
fluid conforming to DOT 3 or DOT 4
specification.
CAUTION
The use of a non-specified fluid
could result in transaxle malfunc-tion and failure.
Use only specified automatictransaxle fluid. (Refer to“Recommended lubricants andcapacities” in section 8.)

Maintenance
24
7
COOLANT
Inverter coolant
The high-pressure cooling system has a
reservoir filled with year-round antifreeze
coolant. The reservoir is filled at the fac-
tory.
Check the antifreeze protection and
coolant level. If it is near or at MIN, add enough coolant
between MIN and MAX and check the
cooling system for air bleed at an author-
ized HYUNDAI dealer.
Engine coolant
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 per every day, at the begin-
ning of the winter season, and before
traveling to a colder climate.
Checking the coolant level
CAUTION
Do not mix-up the caps of engine
coolant and inverter coolant.
If mixed-up it could create a coolantcirculation problem for the engineor Hybrid system.
CAUTION
When adding coolant, be carefulnot to overfill.
WARNING
Removing radiator
and inverter coolant
cap
Never attempt to remove the radi- ator and/or inverter coolant cap
while the engine is operating or
hot. Doing so might lead to cool-
ing system and engine damage
and could result in serious per-
sonal injury from escaping hot
coolant or steam.
(Continued)
OYFH071070N-1

725
Maintenance
Check the condition and connections of
all cooling system hoses and heater
hoses. Replace any swollen or deterio-
rated hoses.
The coolant level should be filled
between F and L marks on the side of the
coolant reservoir when the engine is cool.
If the coolant level is low, add enough
distilled (deionized) water to provide pro-
tection against freezing and corrosion.
Bring the level to F, but do not overfill. If
frequent additions are required, see an
authorized HYUNDAI dealer for a cooling
system inspection.
OYFH071005N
(Continued)
The engine coolant and/or invertercoolant level is influenced by
hybrid system temperature. Before
filling the engine coolant and/or
inverter coolant, turn the hybrid
vehicle off, fill the engine coolant
and/or inverter coolant carefully.
Turn the engine off and wait until it cools down. Use extreme care
when removing the radiator and/or
inverter coolant cap. Wrap a thick
towel around it, and turn it coun-
terclockwise slowly to the first
stop. Step back while the pressure
is released from the cooling sys-
tem. When you are sure all the
pressure has been released, press
down on the cap, using a thick
towel, and continue turning coun-
terclockwise to remove it.
Even if the engine is not operat- ing, do not remove the radiator
and/or inverter coolant cap or the
drain plug while the engine and
radiator are hot. Hot coolant and
steam may still blow out under
pressure, causing serious injury.WARNING
The electric motor
(cooling fan) is con-
trolled by engine
coolant temperature,
refrigerant pressure
and vehicle speed. It may some-
times operate even when the
engine is not running. Use extreme
caution when working near the
blades of the cooling fan so that
you are not injured by the rotating
fan blades. As the engine coolant
temperature decreases, the electric
motor will automatically shut off.
This is a normal condition.