Ok I am at a bit of a loss. My blower fan only operates on high on my 03 discovery. I replaced the resistor module with a new one from Rock auto, didn't fix it. I ordered a new resistor that I read could fix the old one, soldered it in and it did not fix it. I had a spare head unit I swapped in, that did not fix it. I also installed a new fan motor just because.. Any ideas what else it could be?