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.
Tires and Wheels
Recommended Cold Tire Inflation PressuresHyundai Elantra AD (2016-2020) Service Manual: Components and Components Location
Components
1. Rear seat back assembly [LH]2. Rear seat back assembly [RH]3. Rear back armrest4. Rear seat cushion assembly
...
Hyundai Elantra AD (2016-2020) Owners Manual: Engine Start/Stop Button. Starting the engine
Whenever the front door is opened, the Engine Start/Stop button will illuminate
and will go off 30 seconds after the door is closed.
WARNING
To reduce risk of serious injury or death, NEVER allow children or any person
who is unfamiliar with the vehicle to touch the Engine Start/Stop button ...