I ahve a 93 astro van. last year the a/c worked no problem. I went to chcarge the system and the compressor is not locking. I know there is a plug to the compressor and i checked for power and there is no power there as i have the ac on max as i tried to charge the system. Now i know there is a a/c relay and fuse where would that might be so i can check it cause under the dash all i see is a a/c-heat circuit breaker.
If the system is empty it will not run till you get some stuff in there and bring up the pressure. You may have to jump the pressure switch if it's stubborn, as it's hard to get anything to fill with the compressor not turning.