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A/C issue in 99 Silverado

I have an issue with my 99 Chevy Silverado with the AC. A couple of weeks ago when it got warm, I put on my A/C. The button lights up, but the compressor will not kick in. I read my repair manual and it said to take the plug out and bypass it with a paper clip. I did this and the compressor kicked on, but not cold. Once I took the wire out, it quit working. I went and bought some Freon (with the valve) and tested the pressure. I bypassed the plug again and the pressure was in the green “good”, but when the compressor cycled, the pressure dropped. Well I put in the smallest amount of Freon, and the pressure went up to 55, which was barely in the yellow “alert” (next stage is red). The compressor kicks in off and on now while plugged in, but no cold air. I appears that I may have been low on Freon, but I am afraid to add more Freon since I am already in the higher pressure are. Anyone have a clue?

Put the gauge on it without the truck running. What is the pressure?

Start the truck, jumper the switch, set everything to max cool/fan. Where does the pressure go when the compressor kicks on?

You can search this site for 100 threads on A/C recharging. Somewhere in the there more than one person is usually saying that you just need to take it to a shop and have someone fix it. If you need to add refrigerant then you have a leak. You can’t fix that on your own and you’re not supposed to vent those refrigerants to the atmosphere.

The other thing about using a pro is that you can have other problems in the system (as you obviously do, even if it is just a switch) and someone with the right training and equipment has to evaluate it.