No ground fault receptacles on a '79 Prowler - I owned one. The power panel in the bedroom has two branches port & starboard. You lost one. Open the cover of the panel with rig unplugged then unscrew each wire and use a wire brush to clean the wire strands and a sharp point ice pick to scratch out the white powder in the holes the wire fits onto. Push-on push-off breakers can het weak. Try them all if any feel soft use KLIXON TOGGLE BREAKERS which are available online. Search Google eBay or Amazon. Take your time and make a project out of the electricals. Replace the power cord if the copper wire strands look purple or brown. Don'tcha just love the push in pull out hookup cord storage? The green & white prowler with jalousie windows was my third RV.