HYUNDAI SONATA 2021 Owners Manual

06
6-27
OIK057080L
Press brake pedal to deactivate AUTO
HOLD
If you did not apply the brake pedal when
you release the Auto Hold by pressing
the [AUTO HOLD] switch, a warning will
sound and a message will appear.
OTM058159L
AUTO HOLD conditions not met. Close
door and hood.
When you press the [AUTO HOLD]
switch, if the driver's door and engine
hood are not closed, a warning will
sound and a message will appear on the
cluster LCD display.
Press the [AUTO HOLD] switch after
closing the driver's door and hood.
Anti-lock Brake System (ABS)
WARNING
An Anti-Lock Braking System (ABS) or
an Electronic Stability Control (ESC)
system will not prevent accidents
due to improper or dangerous driving
maneuvers. Even though vehicle
control is improved during emergency
braking, always maintain a safe
distance between you and objects
ahead of you. Vehicle speeds should
always be reduced during extreme
road conditions. The braking distance
for cars equipped with ABS or ESC
may be longer than for those without
these systems in the following road
conditions.
Drive your vehicle at reduced speeds
during the following conditions:
• Rough, gravel or snow-covered
roads.
• On roads where the road surface is
pitted or has different surface height.
• Tire chains are installed on your
vehicle.
The safety features of an ABS or ESC
equipped vehicle should not be tested
by high speed driving or cornering. This
could endanger the safety of yourself or
others.
ABS is an electronic braking system that
helps prevent a braking skid. ABS allows
the driver to steer and brake at the same
time.

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
6-29
Electronic Stability Control (ESC)
ODN8069018
The Electronic Stability Control (ESC)
system helps to stabilize the vehicle
during cornering maneuvers. ESC checks
where you are steering and where the
vehicle is actually going. ESC applies
braking pressure to any one of the
vehicle's brakes and intervenes in the
engine management system to assist the
driver with keeping the vehicle on the
intended path. It is not a substitute for
safe driving practices. Always adjust your
speed and driving to the road conditions.
WARNING
Never drive too fast for the road
conditions or too quickly when
cornering. The ESC system will not
prevent accidents.
Excessive speed in turns, abrupt
maneuvers, and hydroplaning on wet
surfaces can result in severe accidents.
ESC operation
ESC ON condition
When the ignition switch is in the
ON position, the ESC and the ESC
OFF indicator lights illuminate for
approximately three seconds. After both
lights go off, the ESC is enabled.
When operating
When the ESC is in operation,
the ESC indicator light blinks:
• 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 ESC is active.
• When the ESC activates, the engine
may not respond to the accelerator as
it does under routine conditions.
• If the Cruise Control was in use when
the ESC activates, the Cruise Control
automatically disengages. The Cruise
Control can be reengaged when the
road conditions allow. See "Cruise
Control System" later in this chapter.
(if equipped)
• When moving out of the mud or
driving on a slippery road, the engine
RPM (revolutions per minute) may
not increase even if you press the
accelerator pedal deeply. This is to
maintain the stability and traction of
the vehicle and does not indicate a
problem.

6-30
ESC OFF condition
To cancel ESC operation:
• State 1
Press the ESC OFF button briefly. The
ESC OFF indicator light and message
"Traction Control disabled" will
illuminate. In this state, the traction
control function of ESC (engine
management) is disabled, but the
brake control function of ESC (braking
management) still operates.
• State 2
Press and hold the ESC OFF button
continuously for more than 3 seconds.
The ESC OFF indicator light and message
"Traction and Stability Control disabled"
illuminates and a warning chime sounds.
In this state, both the traction control
function of ESC (engine management)
and the brake control function of ESC
(braking management) are disabled.
If the ignition switch is placed to the
LOCK/OFF position when ESC is off, ESC
remains off. Upon restarting the engine,
the ESC will automatically turn on again.Indicator lights
■ ESC indicator light (blinks)
■ ESC OFF indicator light (comes on)
When the ignition switch is placed to
the ON position, the ESC indicator light
illuminates, then goes off if the ESC
system is operating normally.
The ESC indicator light blinks whenever
the ESC is operating.
If ESC indicator light stays on, your
vehicle may have a malfunction with
the ESC system. When this warning light
illuminates have your vehicle checked by
an authorized HYUNDAI dealer as soon
as possible.
The ESC OFF indicator light comes on
when the ESC is turned off.
WARNING
When the ESC is blinking, this indicates
the ESC is active:
Drive slowly and NEVER attempt to
accelerate. NEVER turn the ESC off
while the ESC indicator light is blinking
or you may lose control of the vehicle
resulting in an accident.
NOTICE
Driving with wheels and tires with
different sizes may cause the ESC
system to malfunction. Before replacing
tires, make sure all four tires and wheels
are the same size. Never drive the
vehicle with different sized wheels and
tires installed.
While Driving

06
6-31
ESC OFF usage
When Driving
The ESC OFF mode should only be used
briefly to help free the vehicle if stuck in
snow by temporarily stopping operation
of the ESC to maintain wheel torque.
To turn ESC off while driving, press the
ESC OFF button while driving on a flat
road surface.
NOTICE
To prevent damage to the transmission:
• Do not allow wheel(s) of one axle to
spin excessively while the ESC, ABS,
and parking brake warning lights
are displayed. The repairs would not
be covered by the vehicle warranty.
Reduce engine power and do not
spin the wheel(s) excessively while
these lights are displayed.
• When operating the vehicle on
a dynamometer, make sure the
ESC is turned off (ESC OFF light
illuminated).
Information
Turning the ESC off does not affect ABS
or standard brake system operation.
Vehicle Stability Management
(VSM)
The Vehicle Stability Management (VSM)
is a function of the Electronic Stability
Control (ESC) system. It helps ensure the
vehicle stays stable when accelerating
or braking suddenly on wet, slippery and
rough roads where traction over the four
tires can suddenly become uneven.
WARNING
Take the following precautions when
using the Vehicle Stability Management
(VSM):
• ALWAYS check the speed and the
distance to the vehicle ahead. The
VSM is not a substitute for safe
driving practices.
• Never drive too fast for the road
conditions. The VSM system will not
prevent accidents. Excessive speed
in bad weather, slippery and uneven
roads can result in severe accidents.
VSM operation
VSM ON condition
The VSM operates when:
The Electronic Stability Control (ESC) is
on.
When operating
When you apply your brakes under
conditions which may activate the ESC,
you may hear sounds from the brakes,
or feel a corresponding sensation in the
brake pedal. This is normal and it means
your VSM is active.
NOTICE
The VSM does not operate when:
• Driving on a banked road such as
gradient or incline.
• Driving rearward.
• ESC OFF indicator light is on.
• EPS (Electric Power Steering)
warning light (
) is on or blinks.

6-32
WARNING
If ESC indicator light () or EPS
warning light () stays on or blinks,
your vehicle may have a malfunction
with the VSM system. When the
warning light illuminates, have your
vehicle checked by an authorized
HYUNDAI dealer as soon as possible.
Driving with wheels and tires with
different sizes may cause the ESC system
to malfunction. Before replacing tires,
make sure all four tires and wheels are
the same size. Never drive the vehicle
with different sized tires and wheels
installed.
Hill-Start Assist Control (HAC)
The Hill-Start Assist Control (HAC)
helps prevent the vehicle from rolling
backwards when starting a vehicle from
a stop on a hill. The system operates the
brakes automatically for approximately
2 seconds and releases the brake after 2
seconds or when the accelerator pedal is
depressed.
WARNING
Always be ready to depress the
accelerator pedal when starting off on
a incline. The HAC activates only for
approximately 2 seconds.
NOTICE
• The HAC does not operate when
the shift button is in P (Park) or N
(Neutral)
• The HAC activates even though the
ESC (Electronic Stability Control) is
off but does not activate when the
ESC has malfunctioned.
Good Braking Practices
WARNING
Whenever leaving the vehicle or
parking, always come to a complete
stop and continue to depress the brake
pedal. Move the shift button into P
(Park) position, then apply the parking
brake, and place the ignition switch in
the LOCK/OFF position.
Vehicles parked with the parking brake
not applied or not fully engaged may
roll inadvertently and may cause injury
to the driver and others. ALWAYS apply
the parking brake before exiting the
vehicle.
Wet brakes can be dangerous! The
brakes may get wet if the vehicle is
driven through standing water or if it
is washed. Your vehicle will not stop as
quickly if the brakes are wet. Wet brakes
may cause the vehicle to pull to one side.
To dry the brakes, apply the brakes
lightly until the braking action returns to
normal, taking care to keep the vehicle
under control at all times. If the braking
action does not return to normal, stop
as soon as it is safe to do so and call
an authorized HYUNDAI dealer for
assistance.
DO NOT drive with your foot resting on
the brake pedal. Even light, but constant
pedal pressure can result in the brakes
overheating, brake wear, and possibly
even brake failure.
If a tire goes flat while you are driving,
apply the brakes gently and keep the
vehicle pointed straight ahead while you
slow down. When you are moving slowly
enough for it to be safe to do so, pull off
the road and stop in a safe location.
Keep your foot firmly on the brake pedal
when the vehicle is stopped to prevent
the vehicle from rolling forward.
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)

6-34
When the system is deactivated:
ODN8069019
The ISG OFF button indicator illuminates.
If the message "Auto Stop is Off.
OIK057173N
Start vehicle manually", appears on the
LCD display with a beep sound, restart
the vehicle manually by depressing the
brake pedal with the vehicle shifted
to P (Park) or N (Neutral). For your
safety, restart the vehicle in the P (Park)
position.
Auto start
To restart the engine in the auto stop
mode
Release the brake pedal.
- When Auto Hold is activated, if you release the brake pedal, the engine will
be in the auto stop state. However, if
you depress the accelerator pedal, the
engine will start again.
The auto stop indicator () goes OFF on
the instrument cluster, when the engine
is restarted.
The engine is automatically restarted in
the following situations.
• The brake vacuum pressure is low
• The engine has stopped for about 5
minutes
• The air conditioning is ON with the fan
speed set to the highest position
• The front defroster is ON
• The battery is weak
• The cooling and heating performance
of the climate control system is
unsatisfactory
• The vehicle is shifted to P (Park) when
Auto Hold is activated
• The door is opened or the seatbelt
is unfastened when Auto Hold is
activated
• The EPB switch is pressed when Auto
Hold is activated
The auto stop indicator (
) blinks in
green for 5 seconds on the instrument
cluster.
While Driving

06
6-35
OIK057086N
The auto start is temporarily deactivated
in the following situations.
When the gear is shifted from N (Neutral)
to R (Reverse), D (Drive) or Manual
shift mode without the brake pedal
depressed. A message "Press brake pedal
for Auto Start" will appear on the LCD
display. To activate auto start, depress
the brake pedal.
To Deactivate the ISG System
• Press the ISG OFF button to
deactivate the ISG system. Then, the
ISG OFF button indicator illuminates.
• Press the ISG OFF button again to
reactivate the ISG system. Then, the
ISG OFF button indicator turns OFF.
ISG System Malfunction
The ISG system may not operate:
When there is a malfunction with the ISG
sensors or the ISG system.
The followings occur, when there is a
malfunction with the ISG system:
• The auto stop indicator (
) will blink
in yellow on the instrument cluster.
• The light on the ISG OFF button will
illuminate.
Information
• When you cannot turn OFF the ISG
OFF button indicator by pressing
the ISG OFF button, or when the
malfunction with the ISG system
persists, contact an authorized
HYUNDAI dealer.
• You can turn off the ISG OFF button
indicator by driving over 50 mph (80
km/h) for up to 2 hours with the fan
speed below the 2nd position. If the
ISG OFF button indicator remains
ON, contact an authorized HYUNDAI
dealer.
WARNING
When the engine is in auto stop mode,
the engine may restart. Before leaving
the vehicle or checking the engine
compartment, stop the engine placing
the ignition switch to the LOCK/OFF
position or remove the ignition key.

6-36
Battery Sensor Deactivation
ODN8A069204
[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.
-Ther

e is a malfunction with the ISG
system.
- The battery is weak.
-The brake vacuum pr

essure 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 Driving