I would still check the battery. When I had my 2007 Cardinal, I couldn't get my slide back in after being hooked up to shore power for several days. The slide out and landing jacks run off of the battery. I took it to the dealership and they replaced the battery and everything was fine. Just a thought, although I am not an expert with electrical stuff. Perhaps someone else will chime in.
2015 Rockwood 8329SS TT
2004 Chevy 2500HD D/A 4X4 CC SB
Andersen Weight Distribution hitch