1994 Chevrolet Other auto A/C

Had bad clutch on ac compressor. Replaced compressor with clutch, drier and filter. Pulled vacuum on system. Checked ok, no apparent leaks. New high pressure switch installed. Tuned on a/c switched to high, blows fuse. Unplugged high pressure switch connector fan stays on, no problem. Turn off a/c, plug in high pressure switch and unplug low pressure connector, turn on a/c /fan stays on does not blow fuse. Turn off a/c plug in low pressure connector blows fuse. Jumper low pressure connector/turn on ac blows fuse. Has one can of freon charge