Hyundai Sonata Hybrid 2021 Owner's Manual page 151

Convenient Features
Battery replacement
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.
5-10
Information
IC WARNING
This device complies with Industry
Canada licence-exempt RSS
standard(s).
OFE048009
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.
ODN8059266
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.