![Hyundai Sonata 2020 Owners Manual While Driving6-36
Battery Sensor Deactivation
ODN8A069204ODN8A069204
[A] : Battery sensor
The battery sensor is deactivated, when
the battery is disconnected from the
negative pole for maintenance p Hyundai Sonata 2020 Owners Manual While Driving6-36
Battery Sensor Deactivation
ODN8A069204ODN8A069204
[A] : Battery sensor
The battery sensor is deactivated, when
the battery is disconnected from the
negative pole for maintenance p](/manual-img/35/16773/w960_16773-319.png)
While Driving6-36
Battery Sensor Deactivation
ODN8A069204ODN8A069204
[A] : Battery sensor
The battery sensor is deactivated, when
the battery is disconnected from the
negative pole for maintenance purpose.
In this case, the ISG system is limitedly
operated due to the battery sensor
deactivation. Thus, the driver needs
to take the following procedures to
reactivate the battery sensor after
disconnecting the battery.
Prerequisites to reactivate the
battery sensor
Switch "ON" and "OFF" the ignition one
time. Park the vehicle for a minimum of 4
hours with the hood and all doors closed.
Pay extreme caution not to connect any
accessories (i.e. navigation and black
box) to the vehicle with the engine in the
OFF status. If not, the battery sensor may
not be reactivated.
Information
The ISG system may not operate in the
following situations. - There is a malfunction with the ISG
system.
- The battery is weak.
- The brake vacuum pressure is low.
If this occurs, have the ISG system
checked by an authorized HYUNDAI
dealer.
NOTICE
• Use only a genuine HYUNDAI
Absorbent Glass Mat (AGM) battery
for replacement. If not, the ISG
system may not operate normally.
• Do not recharge the Absorbent Glass
Mat (AGM) battery with a general
battery charger. It may damage or
explode the Absorbent Glass Mat
(AGM) battery.
• Do not remove the battery cap. The
battery electrolyte, which is harmful
to the human body, may leak out.

While Driving6-138
Change to "winter weight" oil if
necessary
In some climates it is recommended that
a lower viscosity "winter weight" oil be
used during cold weather. See chapter 8
for recommendations. If you aren't sure
what weight oil you should use, consult
an authorized HYUNDAI dealer.
Check battery and cables
Winter puts additional burdens on the
battery system. Visually inspect the
battery and cables as described in
chapter 8. The level of charge in your
battery can be checked by an authorized
HYUNDAI dealer or a service station.
Check spark plugs and ignition
system
Inspect your spark plugs as described in
chapter 8 and replace them if necessary.
Also check all ignition wiring and
components to be sure they are not
cracked, worn or damaged in any way.
Use approved window washer anti-
freeze in system
To keep the water in the window washer
system from freezing, add an approved
window washer anti-freeze solution in
accordance with instructions on the
container. Window washer anti-freeze is
available from an authorized HYUNDAI
dealer and most auto parts outlets. Do
not use engine coolant or other types
of antifreeze as these may damage the
paint finish.
Do not let your parking brake freeze
Under some conditions your parking
brake can freeze in the engaged position.
This is most likely to happen when
there is an accumulation of snow or
ice around or near the rear brakes or
if the brakes are wet. If there is a risk
the parking brake may freeze, apply
it only temporarily while you put the
gear selector lever in P and block the
rear wheels so the car cannot roll. Then
release the parking brake.
Do not let ice and snow accumulate
underneath
Under some conditions, snow and ice
can build up under the fenders and
interfere with the steering. When driving
in severe winter conditions where this
may happen, you should periodically
check underneath the car to be sure the
movement of the front wheels and the
steering components is not obstructed.
Don't place foreign objects
or materials in the engine
compartment
Placement of foreign object or materials
which prevent cooling of the engine, in
the engine compartment, may cause a
failure or combustion. The manufacturer
is not responsible for the damage caused
by such placement.
To keep locks from freezing
To keep the locks from freezing, squirt
an approved de-icer fluid or glycerine
into the key opening. If a lock is covered
with ice, squirt it with an approved de-
icing fluid to remove the ice. If the lock
is frozen internally, you may be able to
thaw it out by using a heated key. Handle
the heated key with care to avoid injury.

07
7-3
If you Have a Flat Tire While
Driving
If a tire goes flat while you are driving:
• Take your foot off the accelerator pedal and let the vehicle slow down
while driving straight ahead. Do not
apply the brakes immediately or
attempt to pull off the road as this
may cause loss of vehicle control
resulting in an accident. When the
vehicle has slowed to such a speed
that it is safe to do so, brake carefully
and pull off the road. Drive off the
road as far as possible and park on
firm, level ground. If you are on a
divided highway, do not park in the
median area between the two traffic
lanes.
• When the vehicle is stopped, press the hazard warning flasher button, move
the shift button into P (Park), and
apply the parking brake, and place
the ignition switch in the LOCK/OFF
position.
• Have all passengers get out of the vehicle. Be sure they all get out on the
side of the vehicle that is away from
traffic.
• When changing a flat tire, follow the instructions provided later in this
chapter.
IF THE ENGINE WILL NOT
START
If the Engine Doesn’t Turn Over
or Turns Over Slowly
• Be sure the shift button is in N (Neutral) or P (Park). The engine starts
only when the shift button is in N
(Neutral) or P (Park).
• Check the battery connections to be sure they are clean and tight.
• Turn on the interior light. If the light dims or goes out when you operate
the starter, the battery is drained.
Do not push or pull the vehicle to start it.
This could cause damage to your vehicle.
See instructions for “Jump Starting”
provided in this chapter.
CAUTION
Push or pull starting the vehicle may
cause the catalytic converter to
overload which can lead to damage to
the emission control system.
If the Engine Turns Over
Normally but Doesn’t Start
Check the fuel level and add fuel if
necessary.
If the engine still does not start, have
your vehicle checked by an authorized
HYUNDAI dealer.

Emergency Situations7-4
Jump starting can be dangerous if done
incorrectly. Follow the jump starting
procedure in this section to avoid serious
injury or damage to your vehicle. If in
doubt about how to properly jump start
your vehicle, we strongly recommend
that you have a service technician or
towing service do it for you.
WARNING
To prevent SERIOUS INJURY or DEATH
to you or bystanders, always follow
these precautions when working near
or handling the battery:
Always read and follow
instructions carefully when
handling a battery.
Wear eye protection designed
to protect the eyes from acid
splashes.
Keep all flames, sparks, or
smoking materials away from
the battery.
Hydrogen is always present
in battery cells, is highly
combustible, and may explode
if ignited.
Keep batteries out of reach of
children.
Batteries contain sulfuric acid
which is highly corrosive. Do
not allow acid to contact your
eyes, skin or clothing.
If acid gets into your eyes, flush your
eyes with clean water for at least 15
minutes and get immediate medical
attention. If acid gets on your skin,
thoroughly wash the area. If you feel
pain or a burning sensation, get medical
attention immediately.
• When lifting a plastic-cased battery,
excessive pressure on the case may
cause battery acid to leak. Lift with a
battery carrier or with your hands on
opposite corners.
• Do not attempt to jump start your
vehicle if your battery is frozen.
• NEVER attempt to recharge the
battery when the vehicle’s battery
cables are connected to the battery.
• The electrical ignition system works
with high voltage. NEVER touch
these components with the engine
running or when the ignition switch
is in the ON position.
Information
An inappropriately disposed
battery can be harmful to
the environment and human
health. Dispose of the battery
according to your local law(s) or
regulations.
NOTICE
To prevent damage to your vehicle:
• Only use a 12-volt power supply
(battery or jumper system) to jump
start your vehicle.
• Do not attempt to jump start your
vehicle by push-starting.
JUMP STARTING

07
7-5
Jump starting procedure
1. Position the vehicles close enough that the jumper cables will reach, but
do not allow the vehicles to touch.
2. Avoid fans or any moving parts in the engine compartment at all times, even
when the vehicles are turned off.
3. Turn off all electrical devices such as radios, lights, air conditioning, etc.
Put the vehicles in P (Park) and set
the parking brakes. Turn both vehicles
OFF.
ODN8A079022ODN8A079022
4. Connect the jumper cables in the exact sequence shown in the
illustration. First connect one jumper
cable to the red, positive (+) jumper
terminal of your vehicle (1).
5. Connect the other end of the jumper cable to the red, positive (+) battery/
jumper terminal of the assisting
vehicle (2).
6. Connect the second jumper cable to the black, negative (-) battery/chassis
ground of the assisting vehicle (3).
7. Connect the other end of the second jumper cable to the black, negative (-)
chassis ground of your vehicle (4).
Do not allow the jumper cables to
contact anything except the correct
battery or jumper terminals or the
correct ground. Do not lean over the
battery when making connections. 8. Start the engine of the assisting
vehicle and let it run at approximately
2,000 rpm for a few minutes. Then
start your vehicle.
If your vehicle will not start after a few
attempts, it probably requires servicing.
In this event please seek qualified
assistance. If the cause of your battery
discharging is not apparent, have your
vehicle checked by an authorized
HYUNDAI dealer.
Disconnect the jumper cables in the
exact reverse order you connected them:
1. Disconnect the jumper cable from the black, negative (-) chassis ground of
your vehicle (4).
2. Disconnect the other end of the jumper cable from the black, negative
(-) battery/chassis ground of the
assisting vehicle (3).
3. Disconnect the second jumper cable from the red, positive (+) battery/
jumper terminal of the assisting
vehicle (2).
4. Disconnect the other end of the jumper cable from the red, positive (+)
jumper terminal of your vehicle (1).

Engine Compartment ........................................................................\
............ 8-3
Maintenance Services ........................................................................\
...........8-4
Owner’s Responsibility ........................................................................\
.................... 8-4
Owner Maintenance Precautions ........................................................................\
.... 8-4
Owner Maintenance ........................................................................\
.............. 8-5Owner Maintenance Schedule ........................................................................\
........ 8-5
Scheduled Maintenance Services ................................................................ 8-7Normal Maintenance Schedule (Smartstream G1.6 T-GDi) ...................................8-8
Maintenance Under Severe Usage Conditions (Smartstream G1.6 T-GDi) ......... 8-11
Severe Driving Conditions ........................................................................\
.............. 8-11
Normal Maintenance Schedule (Smartstream G2.5 GDi) ..................................... 8-12
Maintenance Under Severe Usage Conditions (Smartstream G2.5 GDi) ................8-15
Severe Driving Conditions ........................................................................\
..............8-15
Explanation of Scheduled Maintenance Items .......................................... 8-16
Engine Oil ........................................................................\
............................. 8-19
Checking the Engine Oil Level ........................................................................\
........8-19
Checking the Engine Oil and Filter ....................................................................... 8-20
Engine Coolant ........................................................................\
......................8-21Checking the Engine Coolant Level ....................................................................... 8-21
Engine Coolant ........................................................................\
................................ 8-21
Changing Engine Coolant ........................................................................\
.............. 8-23
Brake fluid ........................................................................\
............................ 8-24Checking the Brake Fluid Level ........................................................................\
..... 8-24
Washer Fluid ........................................................................\
......................... 8-25Checking the Washer Fluid Level ........................................................................\
.. 8-25
Air Cleaner ........................................................................\
............................ 8-26Filter Replacement ........................................................................\
......................... 8-26
Climate Control Air Filter ........................................................................\
..... 8-28
Filter Inspection........................................................................\
.............................. 8-28
Filter Replacement ........................................................................\
......................... 8-28
Wiper Blades ........................................................................\
........................ 8-29Blade Inspection ........................................................................\
............................ 8-29
Blade Replacement ........................................................................\
........................ 8-29
Battery ....................................................................\
.......................................8-31For Best Battery Service ........................................................................\
................ 8-32
Battery Recharging ........................................................................\
........................ 8-32
Reset Features ........................................................................\
................................ 8-33
8. Maintenance
8

8-3
08
1. Engine coolant reservoir
2. Brake fluid reservoir
3. Air cleaner
4. Engine oil dipstick5. Engine oil filler cap
6. Windshield washer fluid reservoir
7. Fuse box
8. Battery
ENGINE COMPARTMENT
Smartstream G1.6 T-GDiSmartstream G1.6 T-GDi
Smartstream G2.5 GDiSmartstream G2.5 GDi
The actual engine room in the vehicle may differ from the illustration.ODN8089103/ ODN8089048LODN8089103/ ODN8089048L

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,
move the shift button into the P
(Park) position, place the ignition
switch in the LOCK/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 the for low or under-inflated tires.
WARNING
Be careful when checking your engine
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