I have a 97 Mazda and I notice that the air compressor never shuts off unless I turn the A/C off. I have checked the relay and it is fine. What other control is keeping the compressor clutch from releasing?
Maybe the clutch itself is bad. I’m sure there are other possibilities. I suggest you take the car to a shop with the necessary equipment and expertise to correctly diagnose and repair the problem. I do not consider automotive AC to be a DIY thing.
That’s how the A/C works. Turn the A/C on and the compressor clutch engages. Turn the A/C off and the compressor clutch disengages.