For proper maintenance, safety, and maximum fuel economy, you must always maintain recommended tire inflation pressures and stay within the load limits and weight distribution recommended for your vehicle.
All specifications (sizes and pressures) can be found on a label attached to the driver’s side center pillar.
Hyundai Sonata LF 2014-2019 Service Manual: Seat Belt Buckle Switch (BS) Repair procedures
Removal
1.
Disconnect the battery negative cable, and wait for at least three minutes before beginning work.
2.
Remove the front seat assembly.
(Refer to Body - "Front Seat Assembly")
3.
Loosen the seat belt buckle mounting bolt and remove the seat belt buckle switch (A).
Installation
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Hyundai Sonata LF 2014-2019 Owners Manual: 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 90 feet [30 m]).
The remote key battery is weak.
Other vehicles or objects may be blocking the signal.
The weather is extremely cold.
The remote key is ...