hello hoping to get some help with an electrical issue. i bought a 2006 starcraft antigua 215sso and everything works when i have it plugged in. but when it isnt plugged the only thing that works is the slide out.... no interior lights. i use to have a pop up and you could switch it from converter to battery. the antigua does this automatically or atleast thats how i understand it from the manual. or am i missing something? this is my second camper im assuming lights. heater should work off the battery? any help would be greatly appreciated