I just had a very frustrating experience with this issue. Called for repair and they changed out the control board, charging me $750. This did not fix the issue and the repair person disappeared. Didn't return calls. Didn't come back when promised. Sigh. After reading thru several threads on this, I decided to try just replacing the thermistor that's part of the evap cover instead of buying the whole thing. I found part W10316760 on Amazon for under $10. Figured I might as well try. Turns out it worked to fix things. So it appears the whole thing can be fixed by just replacing the thermistor. I gather that KA wants you to change out the whole cover/fan/harness, but if it's just the thermistor, what are the odds that it's different than a normal one? Will see how this holds up over time, but for now I'm glad I didn't spend any more money than I already have dealing with a shady repair person.