Mechanical Key

Turn the key toward the rear of the vehicle to unlock and toward the front of the vehicle to lock.
If you lock the door with the key, all doors lock automatically. From the driver's door, turn the key to the right once to unlock the driver's door, and once more within 4 seconds to unlock all doors.
When the doors are unlocked, they can be opened by pulling the door handle.
When closing a door, push the door with your hand. Make sure the doors are securely closed.
✽ NOTICE
You can set the system to the central door unlock mode (unlock all doors by turning the key to the right once). If you want to use this function, perform the following steps:
Changing the unlock mode (two-stage unlock mode ↔ central door unlock mode)
The unlock mode alternates each time the lock and unlock buttons on the remote key (or smart key) are pressed simultaneously for 4 seconds or more. The hazard warning lights flash four times to indicate the mode change is complete.
Test yourself
A quick Hyundai Tucson LM quiz: every answer comes with an explanation and a link to the manual page.