I'm afraid that you are going to need a mobile RV tech, as all the 12 volt systems have been exposed to 24 volts, and you need someone who will know what to look for. Most of the boards may have a fuse that has popped, but finding them and changing them will be a challenge. If you have to replace the boards, it is going to be expensive. Some of the things that may be affected are; fridge, hot water heater, TV antenna amp, slide out controls, if you have any, converter/charger, and the leveling system. Best of luck, and please let us know how things turn out.