2023 HYUNDAI SONATA key battery

04
4-19
LCD Display Messages
Shift to P or N to start engine
(for smart key system)
This warning message is displayed if
you try to start the engine with the shift
button not in the P (Park) or N (Neutral) position.
Information
You can start the engine with the shift
button in the N (Neutral) position. But, for
your safety, we recommend that you start
the engine with the shift button in the P (Park) position.
Shift to P (for smart key system)
This message is displayed if you try to
turn off the engine without the shift
button in P (Park) position.
If this occurs, the Engine Start/Stop
button turns to the ACC position (If you
press the Engine Start/Stop button once
more, it will turn to the ON position).
Low key battery
(for smart key system)
This warning message is displayed if the
battery of the smart key is discharged
while changing the Engine Start/Stop
button to the OFF position.
Press brake pedal to start engine
(for smart key system)
This warning message is displayed if the
Engine Start/Stop button changes to
the ACC position twice by pressing the
button repeatedly without depressing
the brake pedal.
You can start the vehicle by depressing
the brake pedal and then pressing the
Engine Start/Stop button. 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.

05
5-5
Trunk unlocking
To unlock the trunk :
1. Press and hold the Trunk Unlock button (3) on the remote key for more than one second.
2. The hazard warning lights will blink two times and the trunk will be
unlocked.
3. Once the trunk is opened and then closed, the trunk will automatically
re-lock after 30 seconds.
Information
The word “HOLD” is written on the
button to inform you that you must press
and hold the button for more than one second.
Panic button (4)
Press and hold the Panic button (4) for
more than one second. The horn sounds
and hazard warning lights flash for about 30 seconds.
To cancel the panic mode, press any
button on the remote key.
Start-up
For information, refer to the “Key
Ignition Switch” section in chapter 6.
NOTICE
To prevent damaging the remote key: • Keep the remote key away from
water or any liquid and fire. Internal
circuits may malfunction if the inside
of the remote key gets damp (from
liquids or moisture) or if it is heated.
This can exclude the remote key from
being covered under warranty.
• Avoid dropping or throwing the
remote key.
• Protect the remote key from extreme
temperatures. Mechanical key
OIG046004
If the remote key does not operate
normally, you can lock or unlock the
driver’s door by using the mechanical
key.
To unfold the mechanical key, press the
release button on the remote.
To return the key to its stored position,
press the release button and fold the key
back into the remote.
Remote key precautions
The remote key will not work if any of the
following occur: • The key is in the ignition switch.
• You exceed the operating distance
limit (about 30 m [90 feet]).
• The remote key battery is weak.
• Other vehicles or objects may be blocking the signal.
• The weather is extremely cold.
• The remote key is close to a radio
transmitter such as a radio station or
an airport which can interfere with
normal operation of the remote key.
If the remote key does not work
correctly, open and close the door
with the mechanical key. If you have a
problem with the remote key contact an
authorized HYUNDAI dealer.

Convenience Features
5-6
If the remote key is in close proximity to
your mobile phone, the signal could be
blocked by your mobile phone’s normal
operational signals. This is specifically
relevant when the phone is active such
as making and receiving calls, text
messaging, and/or sending/receiving emails.
When possible, avoid placing the remote
key and your mobile phone in the same
location such as a pants or jacket pocket
in order to avoid interference between
the two devices.
Information
This device complies with Industry Canada RSS-210 standard.
Operation is subject to the following three conditions: 1. This device may not cause harmful
interference.
2. This device must accept any
interference received, including
interference that may cause undesired operation.
3. Changes or modifications not expressly
approved by the party responsible
for compliance could void the user’s authority to operate the device.
NOTICE
Keep the remote key away from
electromagnetic materials that block
electromagnetic waves to the key
surface. Battery replacement
OPD046002
If the remote key is not working properly,
try replacing the battery with a new one.
Battery Type: CR2032
To replace the battery:
1. Insert a slim tool into the slot and gently pry open the cover.
2. Using a screw driver, remove the battery cover.
3. Remove the old battery and insert the new battery. Make sure the battery
position is correct.
4. Reinstall the battery cover and key
cover in the reverse order of removal.
If you suspect your remote key might
have sustained some damage, or you feel
your remote key is not working correctly
contact an authorized HYUNDAI dealer.

05
5 -7
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.
IC WARNING
This device complies with Industry
Canada licence-exempt RSS
standard(s).
Operation is subject to the following
two conditions: (1) this device may not
cause interference, and (2) this device
must accept any interference, including
interference that may cause undesired
operation of the device.
Smart Key (if equipped)
„„Type A
ODN8059006
„„Type B
ODN8059007
Your HYUNDAI uses a smart key, which
you can use to lock or unlock a door (and
trunk) and even start the engine even just
carrying the key.
(1) Door Lock
(2) Door Unlock
(3) Trunk Open
(4) Panic
(5) Remote Smart Parking Assist (rearward)
(6) Remote Smart Parking Assist (forward)
(7) Remote Start

05
5-13
Information
This device complies with Industry Canada RSS-210 standard.
Operation is subject to the following three conditions: 1. This device may not cause harmful
interference.
2. This device must accept any
interference received, including
interference that may cause undesired operation.
3. Changes or modifications not expressly
approved by the party responsible
for compliance could void the user’s authority to operate the device.
NOTICE
Keep the smart key away from
electromagnetic materials that blocks
electromagnetic waves to the key
surface.
NOTICE
Always have the smart key with you
when leaving the vehicle. If the smart
key is left near the vehicle, the vehicle
battery may be discharged. Battery replacement
OFE048009
ODN8059266
If the Smart Key is not working properly,
try replacing the battery with a new one.
Battery Type: CR2032
To replace the battery:
1. Remove the mechanical key.
2. Use a slim tool to pry open the rear cover of the smart key.
3. Remove the old battery and insert the new battery. Make sure the battery
position is correct.
4. Reinstall the rear cover of the smart
key.
If you suspect your smart key might have
sustained some damage, or you feel
your smart key is not working correctly,
contact an authorized HYUNDAI dealer.

Convenience Features
5-14
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 regulation.
IC WARNING
This device complies with Industry
Canada licence-exempt RSS
standard(s).
Operation is subject to the following
two conditions: (1) this device may not
cause interference, and (2) this device
must accept any interference, including
interference that may cause undesired
operation of the device.
Immobilizer System
The immobilizer system protects your
vehicle from theft. If an improperly
coded key (or other device) is used, the
engine’s fuel system is disabled.
When the ignition switch is placed in
the ON position, the immobilizer system
indicator should come on briefly, then
go off. If the indicator starts to blink, the
system does not recognize the coding
of the key. Turn the ignition switch to
the LOCK/OFF position, then turn the
ignition switch to the ON position again.
In some circumstances, the vehicle may
not recognize your smart key if another
smart key device is nearby or a metal
object such as a key chain is causing
interference with the smart key.
If this occurs, your vehicle may not
start. Remove any metal objects or
additional keys near the smart key before
attempting to start the vehicle again.
If the system repeatedly does not
recognize the coding of the key, it is
recommended that you contact your
HYUNDAI dealer.
Do not attempt to alter this system
or add other devices to it. Electrical
problems could result that may make
your vehicle inoperable.
WARNING
In order to prevent theft of your
vehicle, do not leave spare keys
anywhere in your vehicle. Your
immobilizer password is a customer
unique password and should be kept
confidential.
NOTICE
The transponder in your key is an
important part of the immobilizer
system. It is designed to give years
of trouble-free service, however you
should avoid exposure to moisture,
static electricity and rough handling.
Immobilizer system malfunction could
occur.

05
5-17
In case of an emergency
ODN8059291
If the electrical power door lock switch
is not operating (ex. dead car battery)
the only way to lock the door(s) is
with the mechanical key from the out -
side key hole.
Doors without an outside key hole can be locked as follows:
1. Open the door.
2. Insert the key into the emergency door lock hole and turn the key horizontally to lock.
3. Close the door securely.
i Information
If the electrical power to door lock
switch is not operating (ex. dead car
battery) and the trunk is closed, you
will not be able to open the trunk until
power is restored.
Operating Door Locks from
Inside the Vehicle
With the door handle
ODN8059012
Front door
If the inner door handle is pulled when
the door is locked, the door will unlock and open.
Rear door
If the inner door handle is pulled once
when the door is locked, the door will unlock.If the inner door handle is pulled
once more, the door will open.

05
5-53
Inside the vehicle
When you can not unlock the trunk due
to battery discharge or other reasons,
you can unlock the trunk inside the
vehicle.
ODN8059045L
Open the cable cover(1) under the rear
seat with a mechanical key and pull the
cable (2) for unlocking the trunk.
The cable is firmly fixed so it may hard to
pull. Therefore, please use a tool such as
a screwdriver to assist in pulling the loop
for the emergency release.
Smart Trunk with Auto Open (if equipped)
ODN8059046L
On a vehicle equipped with a smart key, the trunk can be opened using the Smart
Trunk with Auto Open system. How to use the Smart Trunk with
Auto Open
The trunk can be opened with no-touch
activation satisfying all the conditions
below.
• After 15 seconds when all doors are
closed and locked
• Positioned in the detecting area for more than 3 seconds.
Information
• The Smart Trunk with Auto Open does not operate when:
- The smart key is detected within 15 seconds after the doors are closed and locked, and is continuously detected.
- The smart key is detected within 15 seconds after the doors are closed and locked, and within 1.5m (60inches)
from the front door handles. (for
vehicles equipped with Welcome Light)
- A door is not locked or closed.
- The smart key is in the vehicle.
1. Setting
To activate the Smart Trunk with Auto
Open, go to User Settings Mode and
select Smart Trunk on the LCD display.
For more information, refer to the “LCD
Display” section in this chapter. If your
vehicle is equipped with additional
navigation, please refer to the
infotainment system manual separately supplied.