2008 (58) Volvo FH13 520 Fridge

Hi guys, anyone help? My fridge which is located above and behind passenger seat has turned from a fridge into a freezer! The front panel controls have stopped working and cannot turn it off or on. When l turn the ignition it comes on but seems to be stuck in freeze mode. I replaced the circuit board for the front panel controls to no avail and that’s where l’m at.
Any advise would grateful be appreciated