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: Engine Room Under Cover Repair procedures
Removal and Installation
1.
Loosen the mounting clip and bolt and then remove the under cover (A).
Tightening torque:
7.8 ~ 11.7N.m (0.8 ~1.2kgf.m, 5.7 ~ 8.6 lb-ft)
2.
Install in the reverse order of removal. ...
Hyundai Sonata LF 2014-2019 Service Manual: Exhaust Manifold Repair procedures
Removal and Installation
1.
Remove the engine cover.
2.
Disconnect the battery negative terminal.
3.
Remove the air cleaner assembly. (Intake And Exhaust System - "Air Cleaner")
4.
Remove the front muffler. (Intake And Exhaust System - "Muffler")
5.
Remove the intercooler inlet ...