What does the oil pressure sending unit do on an Kaw 25(Toro model 74245)? The reason I'm asking is I just bought this unit and found the wire that is suppose to go to the sender disconnected. It ran fine disconnected, I reconnected it, it still runs fine. I guess if it is a normally open switch that closes and shorts something to ground upon losing oil pressure this would make sense. Can anyone tell me how this particular unit functions?