need help! 2012 Itasca Reyo not charging house batteries

follow up: rather than chase gremlins I ended up running a new wire to the small terminal on the solenoid. I made sure it was a switched power circuit and not a constant power one. I used a wire going from the hydraulic reservoir solenoid for the jacks, which one terminal is hot when key is on, and ran it a couple feet over to the isolator small terminal and now it charges just fine