Dead batteries fix
Yep, battery cut off switches worked for us. Same problem you had with both coach and chassis batteries going dead after storing the RV for only two weeks.
I installed a "knife" style cut off on the chassis battery and I trip the breaker on the house batteries. The breaker is located just to the left of the batteries.
Push the button and a "flag" pops out disconnecting the batteries. Easy.
Zero problems since cutting off the batteries during storage now.
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