Norcold NR740BB thermistor problem?

RazMaTaz

We purchased a T@B in 2015 with the above model 110V AC/12V DC refrigerator.  We turn it on and it works fine, but it will shut off at some point and we have to "tap" on the little knob inside the freezer and it will come back on.   We've done it time and time again.  Anyone else have this problem?  Is it relatively easy to replace that part if that is the problem?   Thanks for any help.