Dvd loading but will not play - Farenheit DVD34 Car DVD Player

When you mean that the DVD is loading , does it mean that the file is detected and reading . If so please check if the format is recognised by the player. if not try another DVD.
Next if this an old set try to use a cleaner and clean the head.
If this does not clear the fault you will have to open the set and check for the RF from the head , digital processing and drive output. hope this helps, Good day