Just as a friendly warning to all those who encounter a similar problem, if you plug a fan connector into the extruder temp slot on ur board…I don’t know, cus ur dumb enough not to snap a pic of the board b4 u yank out all the connections (definitely not me :P)… it will give you a reading, my 40mm fan gave me a solid reading of 129C. After racking my brain for hours on why my thermistor would only give that one reading (and a few replacement thermistors later D: ), I figured out that they where just plugged in wrong.
Hope this helps someone out there
I did the same thing. I never replaced any parts though. Just kept messing with it and eventually figured it out.
@Kevin_Danger_Powers lucky you, broke 3 thermistors while probing them with multimeter. And they each take a week to get here 
oh well, got it figured out now!
I unplugged the fan from the board once, forgot I did it, and spent three days – off and on – trying to figure out which software settings to change to get it to run again. doh
@allanGEE lol. It happens.