The TPMS Malfunction Indicator will illuminate after it blinks for approximately one minute when there is a problem with the Tire Pressure Monitoring System.
Have the system checked by an authorized HYUNDAI dealer as soon as possible.
NOTICE
If there is a malfunction with the TPMS, the Low Tire Pressure Position Telltale will not be displayed even though the vehicle has an under-inflated tire.
NOTICE
The TPMS Malfunction Indicator may illuminate after blinking for one minute if the vehicle is near electric power supply cables or radio transmitters such as police stations, government and public offices, broadcasting stations, military installations, airports, transmitting towers, etc.
Additionally, the TPMS Malfunction Indicator may illuminate if snow chains are used or electronic devices such as computers, chargers, remote starters, navigation, etc. This may interfere with normal operation of the TPMS.
Hyundai Sonata LF 2014-2019 Service Manual: Relay Box (Passenger Compartment) Repair procedures
Fuse Inspection
1.
Be sure there is no play in the fuse holders, and that the fuses are held securely.
2.
Are the fuse capacities for each circuit correct?
3.
Are there any blown fuses?
If a fuse is to be replaced, be sure to use a new fuse of the
same capacity. ...
Hyundai Sonata LF 2014-2019 Service Manual: Curtain Airbag (CAB) Module Description and Operation
Description
Curtain airbags are installed inside the headliner (LH and
RH) and protect the driver and passenger from danger when side crash
occurs. The SRSCM determines deployment of curtain airbag by using side
impact sensor (SIS) signal.
Never attempt to measure the ...