Yeah, no. If the temperature displayed on the unit is correct and you’ve verified the reading with a separate thermometer then it is not the temperature probe.
It’s not called “ohming out”, it’s called a continuity test, or sometimes ringing out, but ringing out is reserved for long cable runs usually, or that thing audio engineers do to prevent feedback. Checking for resistance is related to a continuity test.
Anyways, it’s easy enough to check if the relay is sticking on, all you do is check to see if the coil is deenergized when the set point has been reached, and you think the control signal should be low ie if the desired temp has been reached the coil for the relay should not be receiving power anymore. If it’s deenergized and the contacts are still closed then the relay is sticking closed. It is also a very easy replacement, and cheap if that’s the case. The other thing that could be wrong is that the little transistor, which is the “switch” for the relay might have failed, which is also easy to test for, or the resistor that pulls the gate (transistor gate) low could be bad.
Worst case scenario is that the output pin on the micro controller is malfunctioning. Also easy to check for if you follow the trace back from the gate on that transistor. Should be “low” when the compressor should be off.
Is it what I asked you what was in the pic I posted a few posts back?
