So I was having those problems with my WiFi card and finally got my board back. Everything was working great except my fan 0 radial fan was not running. I wiggled the cables a little and the fan started. After a while i came back and noticed it was not running again. I tried plugging it into the fan 1 and the same thing happened. I did not learn enough form that and tried fan 2. So there was a short in the fan, and if my research is right, I fried the mosfets. Just to verify on the DuetWiFI these would be the PMV40UN2's correct. TR1, TR9, and TR5. If that is correct, I am guessing that these would work as a replacement -> https://www.digikey.com/product-detail/en/nexperia-usa-inc/PMV40UN2R/1727-1900-1-ND/5056345?utm_adgroup=Semiconductor%20Modules&gclid=EAIaIQobChMI8cmY7eKo2AIVz7XACh3iTAD_EAAYASAAEgIFKvD_BwE
I will also get a 862d+ 2 in 1 SMD Soldering Reworking Station.
It has been a while since the air force when i worked on things like this.
I have DuetWiFI v1.01
Yes that's the correct part. Are you sure that you tried the mosfets - have you tried another fan?
Yeah I tried another fan, I saw the pins ark in the connector the I used fan2