Compressors used before 03 were the old pressed together style that are known to twist when you take the 4 mounting bolts out, and this pinches the O-ring. I have heard of a few instances of this losing all of the system charge, but not very likely. You have the 1 connection at teh compressor for the clutch, and the other connection at teh accumulator for the low pressure cycling switch. Unplug the low pressure switch and put a jumper wire in it and see if it kicks on. Only do it for a few seconds though in case it is low on charge so as to not burn up your compressor from running it dry.