If one of the sensors was at fault it should bring up a fault code.
E1, E2 or E3.
There is one sensor in the fridge and 2 in the freezer.
The exploded view would suggest the freezer air sensor is at the bottom right side.
There is another sensor attached to the evaporator, the defrost sensor.
The freezer fan will run for a short time when the door is closed.
It will then run once the appliance has reached -18 deg C on the evaporator sensor.
If your compressor is running all the time then it would suggest a system fault, compressor, lack of gas or even a blockage in the system.
If it's switching on and off it would suggest a sensor fault.
Hope this helps
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