My freezer is way too cold, refrigerator is freezing food and temp readings on front panel are not accurate.

Freezer Fridge
Set temp. 0 37
Display read. 21 37
Actual temp. -15 46

The temps vary quite a bit throughout the day. Currently the refrigerator side is close to normal but foods will sometimes freeze. I can see ice build up inside the hole behind the ice maker where the wires come through. I’ve cleaned the vents and coils on the back of the fridge and already replaced the defrost sensor and the front panel. The panel was only replaced because several of the lcd segments were failing on the old panel. Temperatures displayed on the new panel are consistent with what the old panel had been showing. I have a replacement temp sensor for the freezer but haven’t been able to determine its location.

I’m hoping someone here can help me narrow down what parts I should try replacing next and also I need to know where I can find the tech sheet for this model. Whatever would tell me what all of the diagnostic codes mean when in service mode on the front panel and chart that tells me what the ohm readings should be for the sensors at specific temperatures.

Andy