You will need a shop with a tech 2 scan tool (usually the dealer), or an AC repair shop to diagnose those 4 items. I'm sure there's a way to test with a multi-meter, which may be what the AC shop would do, but I can't tell you how. Sorry

 

That really sucks...I try to avoid all shops.. well I guess I'll do some more research and keep trying. Thanks for your help.

 

Yah, I avoid all shops too, but that's why I have my own Tech 2 and factory service manual. I don't trust shops.

 

It doesn't really seem like your issue to me but my '03 was starting to run hotter than normal from the fans not coming on. My problem was actually a battery with low voltage. I cannot remember the voltage spec but our cars have a power save mode that doesn't give any notification it's turned on. One of the things the car will cut power to in order to save the volts are the cooling fans.
No codes, no lights, nothing.
The compressor diode should be in the underhood fuse panel and won't be the problem. It's only there to stop voltage spikes from damaging the pcm.

Without doing any diagnostics your problem sounds like a defective a/c pressure/cycling switch. Buy acdelco for anything electrical on our cars. Nothing is better for them.

 

Thanks for your response. I'm going to look into that part and try a battery from a different car.... Thanks for bringing this back to life.!

 

So to confirm this switch may be causing my cooling fans to not turn on which causes my ac not to blow cold? My ac compressor clutch is engaging when I turn the a/c on

 

It is possible that the switch would stop the fans from turning on yes. If the car never overheats or runs hotter than mid gauge I'd say the fans are coming on just not when you've got the hood up or parked idling. Unless the t-stat is stuck wide open or missing.

 

The temp Guage never goes above the half by much and I think the t Stat has been replaced with a 185... Not for sure though. I have driven the car and then checked the fans and they haven't came on so I'm not for sure if they are coming on...

 

If the temp gauge goes just above half I'd try a good battery with 12.6 volts or better, make sure the connections are clean and tight and see how that goes. Normal temp for these things is half or less. It sounds identical to the issue my car had. But I rarely turn the a/c on so I can't say it's not a separate a/c issue as well.

 

Yeah I'll try another battery to see if that resolves my issue... Thanks