When parked with engine still running, we inadvertently turned on A/C to high. Within a minute we smelled an electrical fire and disconnected the battery. We had it towed to Mercedes Benz. They disassembled the floor board on the drivers side and found all the wiring melted. Mercedes claimed it was Winnebago wiring that caused the problem ( The metal plates that cover the wiring arced and melted the wiring ). We then had it towed to our storage unit where the Progressive Insurance adjustor inspected the damage and denied the claim stating it was Winnebago that caused the problem. He agreed with Mercedes that it was Winnebago's problem. Towed to Winnebago service center and they said it was Mercedes wiring that melted and denied responsibility.