Heater resistor?

Just went through all of the above with my RR. First, I had a bad ground because of paint. Second, I had no high speed. In my case, it's the switch. I opened it up and cleaned the contacts. I still have a high speed issue, but can get it to work in-between med and high, most times. But, you have power it seems, trace down your ground, then maybe the resister.