Ok guys I have a minnkota 3 bank charger, some how I'm getting a feed back on the negative side to my plug for my trolling motor. I unhooked all 3 banks and it goes away. When i plug in the trolling motor i hear a slight pop, even though the trolling motor is off. My meter shows 12 volts from the negative post on the battery to the neg on the plug????? and from the positive post to the neg plug. What am i missing???? Im thinking problems inside the onboard charger.