I live in Connecticut, and don't dry camp much, but do have to worry about "power outage related winter shelter". I have made up a 10 foot extension cord (7 pin male to female extension) so that I can power the trailer, using the TV without having to be in the towing position. The only pins I've used are the 12v battery, and the ground and ICC markers,
Might be a cheap easy fix for a recharge in the brush.
Steve & Jan, Ava & Emma (Mini Schnauzers):
2016 F350 Lariat 4X4 Powerstroke CC/SB "PULLTOY V"
2013 Alpine 3535RE "MAGIC CARPET IV"
Proud Navy Vet!