How to check the layer fans (BCN3D Sigmax)


Allen key 2mm
Philips screwdriver


Layer fans are key to ensure the best quality on your prints, especially when printing PLA, which requires fast cooling when it's printed. Malfunctioning layer fans could lead to overheating issues, more noticeable layers, and overall bad printing quality. 


The layer fan only turns on when the printer is working on a gcode. 

Tip: If you want to check the layer fans function, print this file:

Layer Fans.gcode

You can print it as a regular gcode, simply load it in an SD card and select it to print. 


If the layer fan is not working, follow these steps:

1. Turn off the printer and unplug it from the power outlet.



2. Take out the printhead connection cover and check the connection of the fan in the extruder board.  screw-iconx2 M3 12mm



2. Make sure that the hotend flat cable is well connected by following the instructions in this article: How to check flat cable connections (BCN3D Sigmax)


3. Clean the fans, they should turn smoothly. Check if they have debris stuck around their axles and they are free of dust. You can use a pair of tweezers and dust them with air to clean them. 


4. If the fans still don't work, swap the fans from one head to the other and see if the issue moves to the other side or not. If the problem moves, the fan will need to be replaced. If not, you'll have to replace the extruder board. 

How to replace the Layer Fan (BCN3D Sigmax)

How to replace the Extruder Board (BCN3D Sigmax)



Forum community 

Repair didn’t go as planned? Check out our forum community for troubleshooting help.


It's important to keep your printer in good shape to make the most out of it. In this chart, you can find a list of the extruder maintenance procedures and how frequently these should be done. Maintenance Plan


bcn3d-recycle  Take your e-waste to a certified recycler. Check how we do it in BCN3D.


Parts   Buy these parts
cooler-fan-bcn3d Sigma/Sigmax Layer Fan

SKU 10916


Extruder board

SKU 16100



check flat cable ES

check mainboard fuse ES


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