12 volt battery HYUNDAI SONATA 2021 Owners Manual

Instrument Cluster
4-16
Key not in vehicle
(for smart key system)
This warning message is displayed if the
smart key is not in the vehicle when you
press the Engine Start/Stop button.
When attempting to start the vehicle,
always have the smart key with you.
Key not detected
(for smart key system)
This warning message is displayed if the
smart key is not detected when you press
the Engine Start/Stop button.
Press START button again
(for smart key system)
This message is displayed if you were
unable to start the vehicle when the
Engine Start/Stop button was pressed.
If this occurs, attempt to start the engine
by pressing the Engine Start/Stop button
again.
If the warning message appears each
time you press the Engine Start/Stop
button, have your vehicle inspected by
an authorized HYUNDAI dealer.
Battery discharging due to external
electrical devices (if equipped)
This message is displayed if the battery
voltage is weak due to any non-factory
electrical accessories (ex. dashboard
camera) while parking. Be careful that
the battery is not discharged.
If the warning message appears after
removing the non-factory electrical
accessories, have the vehicle inspected
by an authorized HYUNDAI dealer.
Press START button with key
(for smart key system)
This warning message is displayed if you
press the Engine Start/Stop button while
the warning message "Key not detected"
is displayed.
At this time, the immobilizer indicator
light blinks.
Check BRAKE SWITCH fuse
(for smart key system)
This warning message is displayed if the
brake switch fuse is disconnected.
You need to replace the fuse with a new
one before starting the engine.
If that is not possible, you can start the
engine by pressing the Engine Start/
Stop button for 10 seconds in the ACC
position.

Convenient Features5-42
steering Wheel
Electric Power Steering (EPS)
The system assists you with steering the
vehicle. If the vehicle is turned off or
if the power steering system becomes
inoperative, you may still steer the
vehicle, but it will require increased
steering effort.
Also, the steering effort becomes heavier
as the vehicle’s speed increases and
becomes lighter as the vehicle’s speed
decreases for better control of the
steering wheel.
Should you notice any change in the
effort required to steer during normal
vehicle operation, have the system
checked by an authorized HYUNDAI
dealer.
CAUTION
• If the Electric Power Steering System
does not operate normally, the
warning light (
) will illuminate
on the instrument cluster. You may
steer the vehicle, but it will require
increased steering efforts. Take your
vehicle to an authorized HYUNDAI
dealer and have the system checked
as soon as possible.
• When an abnormality is detected
in the electric power steering
system, to prevent a an accident, the
steering assist function may become
inoperative. At this time, the warning
light turns on or blinks on the cluster.
The steering wheel may become
difficult to control or operate. Have
your vehicle checked immediately,
after moving the vehicle to a safe
area.
Information
The following symptoms may occur during
normal vehicle operation:
• The steering effort may be high
immediately after placing the ignition
switch in the ON position.
This happens as the system performs
the EPS system diagnostics. When the
diagnostics are completed, the steering
wheel effort will return to its normal
condition.
• When the battery voltage is low, you
might have to put more steering effort.
However, it is a temporary condition so
that it will return to normal condition
after charging the battery.
• A click noise may be heard from the
EPS relay after the ignition switch is in
the ON or LOCK/OFF position.
• Motor noise may be heard when the
vehicle is at a stop or at a low driving
speed.
• When you operate the steering wheel
in low temperatures, abnormal noise
may occur. If the temperature rises, the
noise will disappear. This is a normal
condition.
• When an error is detected from the
EPS, the steering effort assist function
may become inoperative in order to
prevent fatal accidents. Instrument
cluster warning lights may be on or the
steering effort may be high. If these
symptoms occur, drive the vehicle to
a safe area as soon as it is safe to do
so. Have the system checked by an
authorized HYUNDAI dealer as soon
as possible.

6-28
Using ABS
To obtain the maximum benefit from
your ABS in an emergency situation,
do not attempt to modulate your brake
pressure and do not try to pump your
brakes. Depress your brake pedal as hard
as possible.
When you apply your brakes under
conditions which may lock the wheels,
you may hear sounds from the brakes,
or feel a corresponding sensation in the
brake pedal. This is normal and it means
your ABS is active.
ABS does not reduce the time or distance
it takes to stop the vehicle.
Always maintain a safe distance from the
vehicle in front of you.
ABS will not prevent a skid that results
from sudden changes in direction, such
as trying to take a corner too fast or
making a sudden lane change. Always
drive at a safe speed for the road and
weather conditions.
ABS cannot prevent a loss of stability.
Always steer moderately when braking
hard. Severe or sharp steering wheel
movement can still cause your vehicle to
veer into oncoming traffic or off the road.
On loose or uneven road surfaces,
operation of the anti-lock brake system
may result in a longer stopping distance
than for vehicles equipped with a
conventional brake system.
The ABS warning light (
) will stay on
for several seconds after the ignition
switch is in the ON position. During
that time, the ABS will go through self-
diagnosis and the light will go off if
everything is normal. If the light stays on,
you may have a problem with your ABS.
Contact an authorized HYUNDAI dealer
as soon as possible.
WARNING
If the ABS warning light () is on and
stays on, you may have a problem with
the ABS. Your power brakes will work
normally. To reduce the risk of serious
injury or death, contact your HYUNDAI
dealer as soon as possible.
CAUTION
When you drive on a road having poor
traction, such as an icy road, and apply
your brakes continuously, the ABS will
be active continuously and the ABS
warning light (
) may illuminate. Pull
your car over to a safe place and turn
the engine off.
Restart the engine. If the ABS warning
light is off, then your ABS system is
normal.
Otherwise, you may have a problem
with your ABS system. Contact an
authorized HYUNDAI dealer as soon as
possible.
Information
When you jump start your vehicle because
of a drained battery, the ABS warning
light (
) may turn on at the same
time. This happens because of the low
battery voltage. It does not mean your
ABS is malfunctioning. Have the battery
recharged before driving the vehicle.
While Driving

06
6-33
The Idle Stop and Go (ISG) system
automatically and temporarily shuts
down the engine when the vehicle
is stopped and idling to improve fuel
efficiency and reduce exhaust gas
emissions. (i.e. red stop light, stop sign,
and traffic jam).
The engine is automatically started upon
satisfying the starting conditions.
The ISG system is always active, when
the engine is running.
Information
When the engine is automatically started
by the ISG system, some warning
lights (i.e. ABS, ESC, ESC OFF, EPS,
and parking brake warning light) may
illuminate for a few seconds due to the
low battery voltage. However, it does
not indicate a malfunction with the ISG
system.
To Activate the ISG System
Prerequisite for activation
The ISG system operates in the following
situations.
• The driver's seatbelt is fastened
• The driver's door and hood are closed
• The brake vacuum pressure is
adequate
• The battery sensor is activated and
the battery is sufficiently charged
• Outside temperature is not too low or
too high
• The vehicle is driven over a constant
speed and stops
• The climate control system satisfies
the conditions
• The vehicle is sufficiently warmed up
• The incline is gradual
• The steering wheel is turned less than
180 degrees and then the vehicle
stops
Information
• The ISG system is not
activated, when the
prerequisites to activate
the ISG system are
unsatisfied. In this case,
the ISG OFF button indicator
illuminates, and the auto stop indicator
(
) illuminates in yellow on the
instrument cluster.
• When the above indicator remains
illuminated on the instrument cluster,
have the IGS system checked by an
authorized HYUNDAI dealer.
Auto stop
To stop the engine in idle stop mode
1.

Decr
ease the vehicle speed to 0 mph.
2.

Depr
ess the brake pedal with the shift
button in D (Drive) or N (Neutral).
The auto stop indicator (
) illuminates
in green on the instrument cluster, when
the engine stops.
Information
The driving speed must reach at least 3
mph (5 km/h) after an idle stop to stop the
engine in idle stop mode again.
In auto stop mode, when the driver
opens the hood, the ISG system will be
deactivated.
ISG (Idle Stop and Go) SyStem ( I f equ I pped)

Emergency Situations
7-4
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 start I ng

08
8-31
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.
WARNING
CALIFORNIA PROPOSITION 65
WARNING
Battery posts, terminals, and related
accessories contain lead and lead
compounds, chemicals known to the
State of California to cause cancer,
birth defects and reproductive harm.
Batteries also contain other chemicals
known to the State of California
to cause cancer. Wash hands after
handling.
NOTICE
• When you do not use the vehicle for a
long time in a low temperature area,
disconnect the battery and keep it
indoors.
• Always charge the battery fully to
prevent battery case damage in low
temperature areas.
BattEry