I have a 36v MinnKota Maxxum. 3 12v batteries ran in a series being charged by a MinnKota MK3150D. My first issue began when I noticed a drastic loss of power in the trolling motor. I traced it back to one of the batteries. Found out it had a NEGATIVE charge. The previous owner was actually charging the battery that ended up reversing polarity on a separate single bank charger and had the cranking battery in a series with 2 of the TM batteries. I thought the single bank charger went bad(I was told by the guy at the battery store) and fried my battery. I replaced the battery and was fine for a couple months(probably one or two outings) until the battery I just replaced reversed polarity like the last one and also fried another battery in the series(it's reading 170v.) PLEASE HELP! I can't afford to pay for diagnostics. I'm thinking that I had a bad connection between these two batteries in the series. Would that cause them to do this? Does how I have them hooked up to the charger interfere with them running in a series?
Also found this junk wired between the 2 batteries in question under shrink wrap.
My current plan is to replace all 3 batteries and all cables/connections but my boat is basically useless until I can afford to do this.
Thank you for your help.
