I have a ProMariner ProSport 12 onboard charger that charges my 2 trolling motor batteries (24v Setup). Recently, I charged them and took the boat out the following weekend. The battery indicator on my Minn Kota remote showed them to have almost no charge. The next day, I removed both batteries and topped them off with distilled water (both were quite low). I checked the charge on these and one was very low and the other was fully charged. I then put them back in my console and hooked everything back up. I plugged up the charged and checked the status a few minutes later. The Battery Bank Trouble Status had Battery 2 lit up. The Trouble shooting reference says this could mean the following: Reverse Polarity, Poor Connections, Battery Too Low to Charge, or Blown Fuse(s). I checked polarity and everything was hooked up correctly. I am almost 100% sure my connections were good because I used a wire wheel on my drill and cleaned every connection before hooking everything back up. I checked all fuses and they were not blown. So, with one of the batteries being low to begin with, I figured it was bad. The battery charger and batteries were purchased at the same time back in 2017. I went and purchased 2 new batteries and hooked everything back up. I plugged in the charged to check status and I am still getting the same Battery Bank Trouble of Battery 2. Has anyone had any issues like this? I wonder if my charger is bad and not charging battery 2? Any tips anyone can share? Thanks in advance.
Definitely check the wires, they can look good and not be good like Tanks suggested.
Maybe swap the charger leads to opposite batteries and see if the fault stays on the same bank\batt. Try it on one batt at a time, switching leads… standard process of elimination type troubleshooting. Also, to check the charger itself, check to see that voltage is going over ~13.3vdc to the battery on charge while actively charging.
And maybe to help others later, never add water to a dead or low charged battery. Always add water after a charge. Then rest it 12 hours and charge again. Always wear eye protection opening batteries.
Fishing Nerd
“No bar, no pinball machines, no bowling alleys, just pool… nothing else.”
No reason to separate the batteries from their series wiring. It is suggested to keep the trolling motor itself unplugged (or trip your breaker) while charging though.
Yes the 2 bank charger should have 2 sets of leads. I suggested swapping the leads to see if the fault follows as a second step in troubleshooting.
Fishing Nerd
“No bar, no pinball machines, no bowling alleys, just pool… nothing else.”
Update: I hooked up my multimeter to both batteries while charger off and while charger on. Battery Leads for Battery 1 is the only one sending out any power. Looks like there is an issue with the leads on Battery 2. I swapped leads on batteries and got the same results.
Going to pull the charger out and try and troubleshoot later this week.
Sucks but unless its a fuse/wiring issue in the charger leads, you’ll likely just have to replace the charger. They are typically epoxy poured and sealed for marine applications, so even changing a minor electronic component is next to impossible. Good news is you’ve found the problem, now you can fix it!
Fishing Nerd
“No bar, no pinball machines, no bowling alleys, just pool… nothing else.”
