Bordercollie wrote:
Most likely that you blew a fuse when you cut through the two wires going to the fan. Fuse is likely to be located in the power panel or in the house battery compartment. You should have a cheap Harbor Freight multimeter or equivalent for checking battery voltage at the two cut wires or other connections and for monitoring your house batteries voltage levels. You can also use meter's Ohm settings to check for good/poor electrical connections. Any RV'er needs to learn to monitor and maintain batteries, connections and electrolyte levels.
Maybe I'm not understanding his post, but it sounds to me that he is not trying to get power to the fan, (which he disconnected) but he has no 12V power for lights etc., unless he is connected to his home's 110/120V power.