2021 HYUNDAI SONATA LIMITED check engine

6-18
Good Driving Practices
• Never shift the gear from P (Park) or
N (Neutral) to any other position with
the accelerator pedal depressed.
• Never shift the gear into P (Park) when
the vehicle is in motion.
Be sure the vehicle is completely
stopped before you attempt to shift
into R (Reverse) or D (Drive).
• Do not shift the gear to N (Neutral)
when driving. Doing so may result
in an accident because of a loss of
engine braking and the transmission
could be damaged.
• While driving up or downhill, check
the gear position, indicated on the
cluster, to ensure the vehicle is
driving forward while in D (Drive), or
backward while in R (Reverse).
If y

ou drive in the opposite direction
of the selected gear, the engine will
turn off and a serious accident may
occur due to the degraded brake
performance.
• Do not drive with your foot resting
on the brake pedal. Even light, but
consistent pedal pressure can result
in the brakes overheating, brake wear
and possibly even brake failure.
• When driving in the manual shift
mode, slow down before shifting to a
lower gear. Otherwise, the lower gear
may not be engaged if the engine
rpms are outside of the allowable
range.
• Always apply the parking brake when
leaving the vehicle. Do not depend on
placing the transmission in P (Park) to
keep the vehicle from moving. •
Exercise extreme caution when
driving on a slippery surface. Be
especially careful when braking,
accelerating or shifting gears. On a
slippery surface, an abrupt change
in vehicle speed can cause the drive
wheels to lose traction and may cause
loss of vehicle control resulting in an
accident
• Optimum vehicle performance and
economy is obtained by smoothly
depressing and releasing the
accelerator.
While Driving

6-24
Parking brake warning light
Check the parking brake
warning light by placing the
ignition switch to the ON
position (do not start the
engine).
This light will be illuminated when the
parking brake is applied with the ignition
switch in the START or ON position.
If the parking brake warning light
remains on after the parking brake
is released while engine is running,
there may be a malfunction in the
brake system. Immediate attention is
necessary.
If at all possible, cease driving the vehicle
immediately. If that is not possible,
use extreme caution while operating
the vehicle and only continue to drive
the vehicle until you can reach a safe
location.
Emergency braking
If there is a problem with the brake
pedal while driving, emergency braking
is possible by pulling up and holding
the EPB switch. Braking is possible only
while you are holding the EPB switch.
However, braking distance will be longer
than normal.
WARNING
Do not operate the parking brake while
the vehicle is moving except in an
emergency situation. It could damage
the brake system and lead to a severe
accident.
Information
During emergency braking, the parking
brake warning light will illuminate to
indicate that the system is operating.
NOTICE
If you continuously notice a noise or
burning smell when the EPB is used
for emergency braking, have system
checked by an authorized HYUNDAI
dealer.
When the EPB (Electronic Parking Brake)
does not release
If the EPB does not release normally,
contact an authorized HYUNDAI dealer
by loading the vehicle on a flatbed tow
truck and have the system checked.
Auto Hold
The Auto Hold maintains the vehicle in a
standstill even though the brake pedal is
not depressed after the driver brings the
vehicle to a complete stop by depressing
the brake pedal.
To apply :
ODN8069015
1. With the driv er's door and engine
hood closed, depress the brake
pedal and then press the [AUTO
HOLD] switch. The white AUTO HOLD
indicator will come on and the system
will be in the standby position.
••CLUSTER
While Driving

6-26
In these cases, the parking brake
warning light comes on, the AUTO
HOLD indicator changes from green
to white, and a warning sound and a
message will appear to inform you that
EPB has been automatically engaged.
Before driving off again, press foot
brake pedal, check the surrounding
area near your vehicle and release
parking brake manually with the EPB
switch.
• While operating Auto Hold, you may
hear mechanical noise. However, it is
normal operating noise.
NOTICE
If the AUTO HOLD indicator changes
to yellow, the Auto Hold is not working
properly. Contact an authorized
HYUNDAI dealer.
WARNING
• Depress the accelerator pedal slowly
when you start the vehicle.
• For your safety, cancel the Auto Hold
when you drive downhill, back up the
vehicle or park the vehicle.
NOTICE
If there is a malfunction with the
driver's door or engine hood open
detection system, the Auto Hold may
not work properly.
Contact an authorized HYUNDAI dealer.
Warning messages
OTM058187L
Parking brake automatically engaged
When the EPB is applied from Auto Hold,
a warning will sound and a message will
appear.
OIK057079N
AUTO HOLD turning Off!
Press brake pedal
When the conversion from Auto Hold to
EPB is not working properly a warning
will sound and a message will appear.
When this message is displayed, the Auto
Hold and EPB may not operate. For your
safety, depress the brake pedal.
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.

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)

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.