Re: electrical glitch
Your battery switch has a "common" post. That is where the +12vdc source for your helm originates. All the posts on your battery switch are +12vdc (commonly red). Just get a simple 12vdc automotive test light at your local autoparts store. Check for power from the common post to -12vdc (commonly called ground) while rotating your switch from off to 1, 2 and 1+2. You should indicate power, if not the problem is between the batteries and the switch and really easy to fix. If you do then get up under the dash and look for the +12v lead that feeds your fuse panel. It should be at least 10ga and red in color. Test it to ground with the test light and see if you have power. If you don't then locate the large black wire at the fuse panel.
Now theres and easy way and a hard way to do this next test. The easy way is to get yourself a long piece of black wire and connect one end to the -12v terminal at the battery then connect the other end to the -12v terminal at the fuse box. This is a temporary jumper that eliminates any possiblity of a problem in any of the grounds. The hard way? Ask me later.
Now, with the battery switch on check for power at the fuse box. If you have it, the problem is with the original ground (all black) wires. If the original wire person did it right, there will be a fuse on the -12vdc side and it's probably blown, you just have to find it.
If you still don't have it then the problem is with the main +12vdc circuit from the common post to the helm. Again, it's probably a blown inline fuse.
However, if reading this has given you some ideas and you want to go hunting for inline fuses then by all means, check them all and possibly save yourself a lot of time and trouble.
