Need AC re-charge advice. Help?

Hi. I posted this question on the vintage board yesterday. Thought I'd try here. I have a 79 280CE purchased with the AC already converted to 134. Last Summer, a home recharge and it worked fine for several months, needing a top off of 134 again in Sept. I didn't need AC until yesterday, and a recharge attempt failed as the compressor/clutch wouldn't kick in in order to suck the freon in. Tha advice I got was to bridge the connection on top of the dryer which would bypass the compressor shut off. Ok, tried that and also tried bridging the two wires to the dryer by pushing a piece of speaker wire into the female spade connections didn't cause the compressor to kick in either. What am I doing wrong? Help?