JPU571

I'm having the same issue with this board on current marlin.

YouTubers are setting this up and it's working for them. Maybe bug in this marlin version?

So basically, it works for you on another board, with an external component.

My fan isnt turning on at all. Even with temp change.

That did not work either. Guess I'm going back to fan being always on for a while.

This guy says to use FAN1_PIN for the hotend fan and in his video it works. https://www.youtube.com/watch?v=4xtsJ-3-c_U

This guy reconfigured the E1 pin to be the auto-fan for E0 to perform this task. I'm about to try this now. https://www.youtube.com/watch?v=KFLSpp5ClUY&t=731s

This works.. but only after I found that I had a bad connection to my fan.. bad connection was caused by me extending the cables [ Ender Extender ] and...

moved everything back to FAN1_PIN and it works as expected for me, after cabling issue was resolved. Fan activates at 50C, turns off at 49C.