Sorry if this has been asked in the past, but I need a little help. I have 3 batteries in my boat... one for starting/house, and 2 for the stereo. I have a perko switch and the one battery is on "1" and the 2 batteries are on "2", there is "All" of course. It's been fine for about 2 years, but recently it all quit charging and working. Can anyone draw me a diagram of the most correct way to wire these batteries in that fashion? Where I can go to "2" to listen to the radio, but then back to "1" to start the boat if those were to die. And then "All" when I'm running across the water to charge everything... thank you in advance!

Also, just to make sure I'm right, the correct way to place a 3 bank charger on this setup. I have the smart charger that monitors and services all of the batteries as they need it