My thetford C263 toilet fan has stopped working. The fan blades aren't seized. All the lights on the control board are fine. There is between 5 and 6 volts at the fan connector at the back of the control panel and I suspect it's a 12V fan so 6V may not be enough to turn it. I have yet to con check the wires to the fan but I think they will be ok. Before I spend out on a new control board, has anyone else seen the same problem? Thanks.