Battery issue???

Well haven't been out in like a month.But try to keep batteries up.so last week 8/29/30 hooked up miink. 3 bank charger after 4 or 6 hrs 2 banks charged. bank 3 not full i unplugged. So today plugged in charger for4hrs. after 2hr bank 1 &2 full charge. bank 3 still charging . Checked bank 3 v. 12.92 Of course it had been on charge. SOO to keep this short ,9or 10 hrs later it was 12.74. you think charger is bad. les than 2yr old. Bank 3 battery is optma agm Maybe 14 /16mo. old???

swap one of the other charger leads and see if battery goes to full charge

Thankd for info will do today think the flood is bout over in n. garland {3 + in..}

i finallyhad time to work on boat. swaped leads on my m.k. charger. Seams like everything is ok? will ck. again on wed thanks for help.

Why do you unplug the battery charger. I dont have a MK charger but I hear they are really good. I have a Dual Pro and they tell you to keep it hooked up to the batteries at all times. They said doing so will help the batteries last longer in general and also hold a daily charge better.

This ^^^^^^^^