Another visitor from the future to say this fix worked. (reversing the fan cable temporarily). It’s the middle one for those unaware. My models started printing awful & melty on one side - turned out the parts fan stopped working.
The weird thing is that usually the printer won’t let you print or do anything if the part fan has issues - but in this instance it’s like the issue is not detected.
I’m so confused I have a brand new p1p and the fan stopped working. I reversed it so the cables face upwards and it works fine now. So confused.
After the cover dropped off and un-plugged
the parts fan, I connected the fan with the wires facing up, because it appear to fit that way, but the wires go down or nothing happens.
I had the part fan on 2 of my 4 P1S units stop working - explains my print quality issues! I did get it fixed, here’s how:
note: I’m an EE by training, and really don’t like the “flip it around” concept while it’s powered on.
The issue seems to be some sticky / gunked-up pins. I fixed it on both of mine with this process:
Confirm the issue:
1: Confirm issue by attempting to turn on the part fan. It should not turn on.
2: Try turning on other fans to confirm it’s just a part fan issue. The other fans should work
The Fix
3. POWER OFF YOUR PRINTER
5. Inspect fan for something stuck in the blades. It should be easy to move the fan with your fingers.
6. Remove the connecter but kinda wiggle/jiggle it as you do remove it.
7. Inspect the connector and socket for debris. Could clean up with contact cleaner or gently fix bent pins
8. Plug in connector with wires up instead of down - this is a mechanical thing to clean up pins and unstick anything that’s stuck
9. Remove connector, and plug in with wires down
10. Power up your printer and repeat checks 1, 2 to see if your fan is working.
If it doesn’t work the first time, try again. Please don’t flip plugs around while it’s powered on, that’s asking for trouble!
Worked for me. Thanks for figuring that out.
What the heck, I had this issue. Found this and it’s worked. Thank you so much for posting this
This worked for me so far as well
I am having an issue with the AUX fan myself. I tried these tricks and i couldn’t bring it back. I am on the latest firmware 01.09.01.00 and I have tried other new AUX fans with no success.
Does anyone have any other tips?
This worked for me today…all was working after p1p to p1s upgrade and then randomly the front fascia was ripped off. Randomly got the error in the app.
So stoked this worked.
This also worked for me. 
thanks. problem will fixed when i change rotation of fan connector
Worked here, too. It’s been driving me nuts since the printer first arrived about a month ago.
Hi
The trick is not compatible with p2s
I’m stuck with this error since I change the extruder-connection-board