The air intake control button’s regulate the airflow in your Hyundai. When the recirculated air option is selected, the air inside the car is recycled through the vents.
When the indicator light is off, that is called fresh mode. That means fresh outside air is coming in to the cabin.
Note about floor mode. The airflow mode selection button controls the direction of the airflow through the HVAC’s system. When the floor level mode is selected, most of the airflow is directed to the floor with a small amount of air being directed to the windshield and side window defrosters.
To get better airflow to the rear seats, adjust the front vents so the air flows around the two front passengers’ seats. You may also want to try the bilevel airflow mode which directs air towards the face and feet. Because the rear passengers have a floor level vent coming from under the front seats. All of these functions are automatically controlled by using the auto feature if equipped. You can do this by adjusting the temperature to a comfortable setting and then press auto.