I recently purchased a 1968 Caravel. There is not a battery hooked up. There are four 20amp circuits. Only 3 are wired. I'm guessing that the fourth circuit is for AC. Circuit one is the only circuit that works and that is a 12V circuit in the front end of the unit. The second circuit which powers the range hood fan, light over kitchen sink and roof vent fan does not work. Also the 120V general purpose circuit does not work. I have checked all fuses in the univolt system and they are all good. This AS was in a shed for the past 13 years. Does anyone have any suggestion? Thanks, Bob