Can anyone help me with this treadmill. I plugged it in and it started to work. Couple seconds in shut off and now the screen won’t turn on. When plugged in the white box I am pointing to gets really hot and nothing seems turns on. I checked the fuses both seem fine. Anyone could help thanks.

 

That appears to be the low voltage (12v?) supply to the motor control board.
Probably need to remove the whole board, noting all connections and trouble shoot it on the bench.
Max.