Make this adjustment before you start driving and while the day/night lever is in the day position.
Pull the day/night lever towards you to reduce glare from the headlights of the vehicles behind you during night driving.
Remember that you lose some rearview clarity in the night position.
Hyundai Elantra AD (2016-2020) Service Manual: Fuel Tank Pressure Sensor (FTPS) Description and Operation
Description
Fuel Tank Pressure Sensor (FTPS) is a component of the
evaporative emission control system and is installed on the fuel tank,
the fuel pump, or the canister. It checks the purge control solenoid
valve operation and detects a leakage of the system. ...
Hyundai Elantra AD (2016-2020) Owners Manual: SRS Care
The SRS is virtually maintenancefree and there are no parts you can safely service
by yourself. If the SRS air bag warning light does not illuminate when the ignition
switch is in the ON position, or continuously remains on, have your vehicle immediately
inspected by an authorized HYUNDAI deal ...