This page outlines the procedure for diagnosing and fixing a printhead that fails to extrude.
The This first section gives a background on the parts of the printhead and to help understand how jams can occur, or you can skip to the Troubleshooting Guide.
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Remove the filament elbow and inspect for broken filament or filament runout.
Preheat the printhead and select the “load filament” command on the printer screen. Check to see if the Drive Gears are spinning. If the Drive Gears are spinning but the filament does not feed, there is a jam in the Heatbreak or the nozzle. If the Drive Gears do not spin there is an issue with the Extruder in which case contact customer support.
Remove the nozzle using guide Replace a Nozzle . With the printhead preheated, select “load filament” and help feed the filament above the printhead manually as shown in the image below, use lots of force. If filament extrudes from the HeatBlock, the nozzle was jammed and you can install a new nozzle. If the printhead does not feed filament with the nozzle removed proceed to the next step.
With the printhead preheated, the nozzle removed, and the filament elbow raised, depress the tension lever with one hand and quickly pull up hard on the filament with your other hand. If you are able to remove the filament, trim off 20cm of the filament with side cutters, and try loading the filament again. If the extruder still fails to extrude, then there is Heatbreak jam and you will need to follow guide Rebuild The Hotend or contact customer support for a new Hotend assembly which you can install with guide Replacing a Hot End .
