2023 HYUNDAI SONATA check engine

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
s ta rt
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.

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.
ODN8A079022
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).

Emergency Situations
7-6
If your temperature gauge indicates
overheating, you experience a loss of
power, or hear loud pinging or knocking,
the engine may be overheating. If this
happens, you should:
1. Pull off the road and stop as soon as it
is safe to do so.
2. Place the shift button in P (Park) and set the parking brake. If the air
conditioning is ON, turn it OFF.
3. If engine coolant is running out under the vehicle or steam is coming out
from the hood, stop the engine. Do
not open the hood until the coolant
has stopped running or the steaming
has stopped. If there is no visible
loss of engine coolant and no steam,
leave the engine running and check
to be sure the engine cooling fan is
operating. If the fan is not running,
turn the engine off.
WARNING
While the engine is running,
keep hands, clothing and tools
away from the moving parts
such as the cooling fan and
drive belt to prevent serious
injury.
4. Check for coolant leaking from the
radiator, hoses or under the vehicle. (If the air conditioning had been in use, it
is normal for cold water to be draining
from it when you stop.)
5. If engine coolant is leaking out, stop the engine immediately and call the
nearest authorized HYUNDAI dealer
for assistance.
If the engIne overheats

07
7-7
WARNING
Your vehicle is equipped
with a pressurized coolant
reserve tank. NEVER remove
the engine coolant reservoir
tank/radiator cap or the drain plug while the engine and
radiator are HOT. Hot coolant
and steam may blow out under
pressure, causing serious
injury.
Turn the engine off and wait until the
engine cools down. Use extreme care
when removing the engine coolant
reservoir tank/radiator cap. Wrap
a towel or thick rag around it, and
turn it counterclockwise slowly to
release some of the pressure from the
system. Step back while the pressure is
released.
When you are sure all the pressure has
been released, continue turning the cap
counterclockwise to remove it.
6. If you cannot find the cause of the overheating, wait until the engine
temperature has returned to normal.
Then, if coolant has been lost,
carefully add coolant to the reservoir
to bring the fluid level in the reservoir
up to the halfway mark.
7. Proceed with caution, keeping alert
for further signs of overheating. If
overheating happens again, call
an authorized HYUNDAI dealer for
assistance.
NOTICE
• Serious loss of coolant indicates a
leak in the cooling system and we
recommend the system be checked
by an authorized HYUNDAI dealer.
• When the engine overheats from
low engine coolant, suddenly adding
engine coolant may cause cracks
in the engine. To prevent damage,
add engine coolant slowly in small
quantities.
• If there is overheating, park your
vehicle in a safe place and do not
turn off the engine until the cooling
fan stops. The engine might get stuck
due to sudden increase of water
temperature.
• Turn off the engine if the cooling fan
does not rotate.

Emergency Situations
7-8
ODN8079002
ODN8049030L
(1) Low Tire Pressure / TPMS Malfunction
Indicator Lamp
(2) Low Tire Pressure / Tire Pressure Monitor / TPMS Malfunction Display
(shown on the cluster LCD display)
Check Tire Pressure
ODN8049022L
• You can check the tire pressure in the
Assist mode on the cluster.
Refer to the “LCD Display Mode”
section in chapter 4.
• A “Drive to display” message will
appear for the first few minutes of
driving after initial engine start up.
If the tire pressure is not displayed
after a few minutes of driving, check
the tire pressures.
• The displayed tire pressure values may
differ from those measured with a tire
pressure gauge.
• You can change the tire pressure unit
in the User Settings mode on the
cluster.
- psi, kpa, bar ( Refer to the “User
Settings Mode” section in chapter 4 ).
Tire Pressure MoniToring sysTeM (TPMs) (if equiPPed)

07
7-9
Tire Pressure Monitoring System
WARNING
Over-inflation or under-inflation can
reduce tire life, adversely affect vehicle
handling, and lead to sudden tire failure
that may cause loss of vehicle control
resulting in an accident.
Each tire, including the spare (if
provided), should be checked monthly
when cold and inflated to the inflation
pressure recommended by the vehicle
manufacturer on the vehicle placard
or tire inflation pressure label. If your
vehicle has tires of a different size than
the size indicated on the vehicle placard
or tire inflation pressure label, you should
determine the proper tire inflation
pressure for those tires.
As an added safety feature, your
vehicle has been equipped with a tire
pressure monitoring system (TPMS)
that illuminates a low tire pressure
telltale when one or more of your tires is
significantly under-inflated. Accordingly,
when the low tire pressure telltale
illuminates, you should stop and check
your tires as soon as possible, and inflate
them to the proper pressure. Driving on
a significantly under-inflated tire causes
the tire to overheat and can lead to tire
failure.
Under-inflation also reduces fuel
efficiency and tire tread life, and may
affect the vehicle’s handling and
stopping ability.
Please note that the TPMS is not a
substitute for proper tire maintenance,
and it is the driver’s responsibility to
maintain correct tire pressure, even if
under-inflation has not reached the level
to trigger illumination of the TPMS low
tire pressure telltale.
Your vehicle has also been equipped with
a TPMS malfunction indicator to indicate
when the system is not operating
properly. The TPMS malfunction
indicator is combined with the low
tire pressure telltale. When the system
detects a malfunction, the telltale will
flash for approximately one minute and
then remain continuously illuminated.
This sequence will continue upon
subsequent vehicle start-ups as long as
the malfunction exists.
When the malfunction indicator is
illuminated, the system may not be able
to detect or signal low tire pressure as
intended. TPMS malfunctions may occur
for a variety of reasons, including the
installation of replacement or alternate
tires or wheels on the vehicle that
prevent the TPMS from functioning
properly.
Always check the TPMS malfunction
telltale after replacing one or more tires
or wheels on your vehicle to ensure that
the replacement or alternate tires and
wheels allow the TPMS to continue to
function properly.
NOTICE
If any of the below happens, have
the system checked by an authorized
HYUNDAI dealer.
1. The Low Tire Pressure TPMS Malfunction Indicator does not
illuminate for 3 seconds when the
ignition switch is placed to the ON position or engine is running.
2. The TPMS Malfunction Indicator remains illuminated after blinking for
approximately 1 minute.
3. The Low Tire Pressure LCD display remains illuminated

Emergency Situations
7-22
SYMPTOM
PROBABLE CAUSE
Starter won’t function
Engine turns over but will not start
Engine misfires
Engine overheats
Engine stops while driving driving
Fuel consumption is excessive
Brake pedal is spongy
Braking power is insufficient
Steering wheel is heavy
Steering wheel shakes
Steering wheel pulls to one side while driving
Vehicle pulls to one side while braking
Tire wear is abnormal
Charge warning light comes on while driving
Wipers, horn or lights won’t funciton
Battery discharge is excessive
Ignition circuit faulty O O Ignition coil or condensor faulty O O O
Distributor faulty O
Alternator belt loose O O O O O Check fuses, bulbs or wiring O
Brake dragging O O
Shift lever not positioned in
"P" or "N" range O
Frequent driving in lower gear O
Air intrusion into brake lines O
Brake fluid insufficient O
Brake disc and pads wet O O
Brake pad wear O O
Wheel alignment incorrect O O O O O O Wheel balance incorrect O O
Tire pressure incorrect
(too low or high) O O O O
Tire size incorrect O

Engine Compartment .................................................................................... 8-3
Maintenance Services ................................................................................... 8-5
Owner’s Responsibility ............................................................................................ 8-5
Owner Maintenance Precautions ............................................................................ 8-5
Owner Maintenance ...................................................................................... 8-6
Owner Maintenance Schedule ................................................................................ 8-6
Scheduled Maintenance Services ................................................................ 8-8
Maintenance Schedule (Smartstream G1.6 T-GDI) ................................................8-8
Maintenance Schedule (Smartstream G2.5 GDI) ..................................................8-12
Maintenance Schedule (Smartstream G2.5 T-GDI) ...............................................8-16
Explanation of Scheduled Maintenance Items ..........................................8-20
Engine Oil ..................................................................................................... 8-23
Checking the Engine Oil Level ............................................................................... 8-23
Checking the Engine Oil and Filter ....................................................................... 8-25
Engine Coolant ............................................................................................. 8-26
Checking the Engine Coolant Level ...................................................................... 8-26
Changing Engine Coolant ...................................................................................... 8-28
Brake Fluid .................................................................................................... 8-29
Checking the Brake Fluid Level ............................................................................. 8-29
Washer Fluid ................................................................................................. 8-30
Checking the Washer Fluid Level .......................................................................... 8-30
Air Cleaner ..................................................................................................... 8-31
Filter Replacement .................................................................................................. 8-31
Climate Control Air Filter ............................................................................. 8-33
Filter Inspection...................................................................................................... 8-33
Filter Replacement ................................................................................................. 8-33
Wiper Blades ................................................................................................ 8-34
Blade Inspection .................................................................................................... 8-34
Blade Replacement ................................................................................................ 8-34
Battery .......................................................................................................... 8-36
For Best Battery Service ........................................................................................ 8-36
Battery Recharging ................................................................................................ 8-37
Reset Features ........................................................................................................ 8-37
8. Maintenance
8