1999 Maxum SCR41, Inverter alarm going off while under power, starb eng gauge reads 16 V, Port 14. alarm on inverter reading 16.2. got back to port shut her down. a week later. gene and Starb eng wont turn over, Port started. as soon as it started the inverter alarm went off. I tested going into the inverter 16.2 with engine running, turn Port engine off 13.1, turn engine back on alarm comes back on, same high voltage. tested from batteries while engine on. Battery 1 reads 13.1, Batt 2 reads 16.5, turn engine off 14.1 from Batt 2. There is what looks like a power distribution bar that the red cable go to from each battery. 5 posts marked A1&2 and B1,2,3, with the port engine on I get a reading on post A1 - 17 V, that goes to my port alternator, A2 - 5 v goes to my Starb alternator , B1 - 16.3 goes to Battery 2, B2 post I get a reading of 16.3 goes to Batt 2 and B3 gets goes to one of my house Batt. Cause of over charge I need help with.