See also:

Why didn’t my air bag go off in a collision? (Inflation and non-inflation conditions of the air bag)
There are many types of accidents in which the air bag would not be expected to provide additional protection. These include rear impacts, second or third collisions in multiple impact accidents, ...

High Mounted Stop Light
If the light bulb is not operating, have the vehicle checked by an authorized Hyundai dealer. ...

Replacing the battery
When the transmitter's battery begins to get weak, it may take several pushes on the button to lock or unlock the doors, and the LED will not light. Replace the battery as soon as possible. B ...