I have a new 3 bank Pro Mariner Pro Sport 20 charger and it is throwing a default code .My two trolling motor batteries are up from by the charger and the starting battery is in the back on my pontoon boat.It is ain the slip and I can not get to the wires under it to check.I believe it is the wires to the starting battery maybe, Can it just disconnect the one bank and will it still work on the trolling batteries?
I know I need to pull it out of the slip and check the wires , Just trying to charge the two up front for now. Maybe it is because the backbattery is at least 25 feet it is to long for it to charge ?

Switch that battery with one of the others and that should tell you if it’s the battery . But to answer your question, I’ve unhooked one battery off my 4 bank before for a couple of weeks. I had no issues.

Thanks what I am going to do .

I called their tec department and they said to hook two leads on one battery and one on another and it would work. Bingo it works.
At first I tried just leaving one un hooked and it still threw a code . They said it would if not connected.