While rewiring my boat for bilge pumps and hi water alarms, I discovered the boat uses white as the hot sometimes. I found the trim tabs are reversed from Port and Stbd. The Previous wire that was feeding the 4 amp bilge pump and the stern 20 amp bilge pump were wired in parallel and fed from a 15 amp breaker and had #16 gauge wire coming off of the breaker. When either float was closed both pumps operated. Now I know why the pumps were triping the breaker and the wires have turned black from over heating. The auto pilot has #16 feeding the auto pilot system and they used both wires so it could carry the amps to the auto pilot. I am going with the correct wire size and use tinned wire. I know that sometimes it is cheaper to run wire to a switch and have black going out from the breaker and use the white coming back and then off to the load. When ever wiring a boat make sure you understand that colors of wire can be black and white, black and red or now the new color is red and yellow. I am not bad mouthing the Blackman Electricians or Blackman boats Co. or a previous boat owner. Sometimes you do what is needed to make things work. Just letting people know that you never know what someone has done to the boat after it come from the factory. Sure glad I did not short out my auto pilot, trim tabs or anything else. I now need to go through the Volvo panel and verify all compn ets are clean and tight. Just having fun accomplishing things on my boat. Great feeling when you find out something is wrong and you can make it better.