Did you already check fpr power "in" and "out" of the switch? 
well i have power on the acc wire. now that ive thought about the relay might be bad too.there is a red wire that should have 12v when still plugged into the switch terminal and switch set to on, but nothing is there. i was going to switch out the swotch with one my brother had but i guess he doesnt have that system anymore. the compressor works with direct power and when i switch the switch to on there is a draw on the system (volt gauge drops). hopefully i can get an answer from them soon. then i can move onto the tank.
