I have a 2008 Mazda 3, and during the winter, we had a few warm, wet days, and I tried using the AC, and it wasn't blowing cold. So now that spring has sprung, I'm looking to get this fixed up. So far I've checked that the clutch is spinning when AC is enabled, not not spinning when AC is turned off inside the car. There aren't any grinding noises.
I bought a can of the refrigerant, (AC Pro), and I hooked that up to the low pressure port, but it shows that the pressure is already in the "Red Zone", which based on my reading means, either the compressor isn't actually working, or I have too much refrigerant, which seems unlikely since I've never added any.
Before I take this to a mechanic, I'm wondering if there is anything else I can check.