Recently, I turned my AC on in my truck and it blew hot air. I initially thought that it needed Freon but the pressure looks good on the low side and when I try to add more freon, it will not take any. After doing some preliminary checking, this is what I have found:

1. When I hit the AC button, the compressor does spin but I do not hear it engage. If I turn the AC button off, the compressor stops spinning but again there is no noise.
2. Pressure on the low side seems to be adequate (30 to 35 psi) or at lease adequate enough where I should get some cooling effect.
3. I do not have a gauge to test pressure on the high side so I am not sure what it is.
4. When trying to add Freon, the system will not take any and the can does not even get cold.

Could this possibly be a bad pressure switch or would a bad pressure switch prevent the compressor from spinning?

Any other ideas as to what I should check or should I just take it to a mechanic?


I am thinking about just changing the pressure switch to see what happens since that seems like an easy fix.