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Front hot end fan not working


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Posted · Front hot end fan not working



Recently the ultimaker pro bundle (printer + filter + material station) that our lab is running has started acting up, this is becuase of a the hot end front fan not spinning causing heat creep and material jam.
I have disassembled the print head's front cover and removed the fan. I have tested both the fan by connecting to 5v, it spins, and the connector on the printhead with a multimeter, outputs 5.1V. But when i plug the fan in it doesnt work, does anyone know how to fix it?


Thank you

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    Posted · Front hot end fan not working

    Often it's the printhead cable that is loose for these types of things so check that first as it is so easy and trivial to do so (takes a minute once you find the hex tool).  The cable along the bowden is constantly pulling upward and it can gradually pull the cable out.  Keep in mind that the cable is held in by a clip so don't just try to pull it out without squeezing the clip thing.  Instructions:




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    Posted · Front hot end fan not working

    That sucks.  Here's the relevant schematics of the PCB in the print head.  The SDA/SCL signals come from the cable.  I guess I'd try one last thing - if the side fans work or if you can dim and brighten the "frame" lights form the maintenance menu then then the problem is in the print head as you can see.  If all 3 things are broken then it's more likely a problem at the other end of that cable you checked.


    Most likely it's the PCB in the print head.  You can order another one.  You might not see it in the website store of your reseller but it's definitely available.  And if your unit is still under warranty it should be free.


    It's most likely the transistor Q1.  If it were me I'd just short out tp1 to ground so the fan is simply always on.  Annoying but at least the printer will start working again.






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    Posted · Front hot end fan not working

    Ugh, that sucks. This seems like a hardware problem.

    Then it's better to reach out to our support experts.
    Especially if your printer arrived dead on arrival. 

    You can create a ticket here to reach out to our support experts: 


    Good luck! 🤞 I hope you get unstuck soon. 

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    Posted · Front hot end fan not working

    there connector must have come loose dor the fan, I recrimped the wire with a new connector and it is workin now.

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