2003 Maxum 4200 electric engine hatch

[StenGem]

For some reason, even though hooked up to shore power, all 3 batteries went dead. Electric engine hatch will not operate. Recharged battery controlling dash switches. Still does not operate. Is there a way to manually open main hatch?
Without hatch fully open, I cannot get to port and starboard batteries to recharge. Any advice welcome! 516 658-6099 or StenGem@aol.com