Carrier 7300 supply temp

Good afternoon fellow truckers!

I got a 2016 carrier 7300x4 with 7xxx hours on it, amazing condition and still works perfectly but as of last week I noticed that when I check my gauges, the supply air temp bounces all over the place. It'll show -10 all the way to -60 in two or three seconds and just bounce all over the place. I spoke with a carrier rep and he said I have to replace the whole display unit which doesn't seem right to me when it could be as simple as a sensor.

Has anybody went through this before or possibly have any ideas? I'm thinking the supply air temp sensor is bad and just needs to be replaced