Air Conditioning does not work

I have a 2000 Nissan Xterra, 2WD, V6 with about 89,000 miles. The air conditioner works about half of the time. When it works, it is ice cold. When it doesn't, it blows warm air. So I know it is not a freon leak. It is pretty much random when it works and when it doesn't, although I believe it works more often when moving then when stopped. However, it will often go warm when driving, and it will sometimes blow ice cold when stopped. It doesn't matter whether it is really hot or cool outside. Toggling the a/c switch doesn't really help either. Turning the A/c off, waiting a few minutes, and turning it back on works sometimes, and sometimes not. Basically, it is pretty random when it does and does not work. Any ideas what the problem might be? Thank you.

In addition to the facts I described, I forgot to mention that often times the a/c will work for like 10 minutes straight, then stop for a few minutes, and then start working again, without touching the a/c button or fan selection switch. And vice versa--sometimes I will turn it on and it won't work, and then all of a sudden cold air starts coming out without touching anything. I figured that might rule out the switch being the problem.

If you ran a hit wire to fuse and it worked, then it sounds like the hot wire on fuse is not hot.

Mine is fixed but thanks

I pulled four wire plug out on top of bottle and tried to unplug the plug at compressor and couldn't get it out, so I put four wire plug back in and cranked it and turned on A/C and it was working good and still is.

Air Conditioning problem
2000 Nissan Xterra 6 cyl Two Wheel Drive Automatic

The A/C cools good when the outside air is cool and when the engine is run for the first time. After it has been shut off, the A/C doesn't cool during hot weather. I checked the low side pressure with one of those R-134 cans with the gauge and it's running at 60psi at idling speed. The pressure goes down to about 40psi with increased RPM's. Sometimes after driving for a long period, the air might begin to cool off. That's about it. Please help.