96 Suburban AC not working

[87Skier]

So I've had my Suburban for a year now and I figure I should fix my AC even though summer is almost over.

Some background: First, I don't work on AC systems much and don't have a lot of prior experience with them. Second, I don't know when the last time it worked was. Third, the suburban has rear AC (not sure if that changes anything).

When I got it I thought I would check out an electrical issue, so I turned on the AC and jumped the pressure switch on the passenger side of the suburban, the compressor kicked on and clutch engaged properly. I immediately disconnected it to prevent damaging the compressor. Next, I thought it might just be low on R-134a so I used my left over recharge kit on the suburban. When I hooked it up and starting charging my system, the compressor kicks on. As soon as I released the trigger, the compressor would turn off.

I'm not really sure where to go from here. Is my system leaking? Do I have a bad switch?

Thanks