Hello. A month ago, I bought a K2 with CFS. This is my first 3D printer. About two weeks ago, the printer started throwing various errors while working with CFS (CM2789-y, FS2843, FR2851, CY2577, TR2852, CM2789-x, 2766, FR2865, FO2845). I removed the CFS and installed filament on the side of the printer. The errors stopped appearing, but I had trouble changing the filament. After pressing “retract,” I can’t eject it. I have to heat the extruder to the appropriate temperature and manually eject the filament by clicking on the screen several times. I also can’t perform cutter calibration. The blue LED is also constantly on. Today, I disconnected the filament sensor and checked it. I don’t see anything wrong. Should I contact Creality about a replacement?
To answer your first question: yes, contact Creality for a warranty replacement if your printer is new. Be aware that they will almost certainly ask you to attempt troubleshooting or a repair before they ship a replacement part.
In the meantime, here are some troubleshooting steps you did not mention trying.
As you noted, the sensor light is lit. Your error message and your photo clearly point to the same issue: the “Material Break Detection Light” is on. That indicates something is blocking the sensor. Filament is what it is designed to detect, but dust and debris can block it as well. That light must be cleared before you can proceed with further diagnostics.
You didn’t mention which K2 model you have, but here is the service video for the K2 Plus detection module as a reference:
- Power off the printer.
Carefully disconnect the connector from the PCB, then remove the two hex nuts and inspect the interior for visible debris. Start by using tweezers to remove anything you can see. An air duster can be used afterward, but be careful not to blow contaminants deeper into the assembly. This is easiest and safest to do with the extruder removed and worked on at a table.
Once you’ve performed the cleaning, if the blue light remains on, include that detail in your warranty request to Creality. It will help reduce back-and-forth with tech support and speed up the resolution.
Mine came with spare parts that also included the sensor.
The printer is a basic K2 Combo model (260x260mm build volume). I disassembled the extruder again. I used a lint-free cloth and isopropyl alcohol. I cleaned the sensor slot, but unfortunately, that didn’t help.
I see that even if I had to buy it myself, this part is cheap: https://www.amazon.pl/wykrywania-filamentu-Creality-akcesorium-ekstruderów/dp/B0F8HW7WT2?ref_=ast_sto_dp
Yes, it is cheap which makes it a viable option to simply replace it as a diagnostic step. If it were a $50 component, I might have to think about it but after going through the amount of work you already went through, $25 is probably time and money well spent and if it isn’t the issue, at least you have a spare, or you can do as I do, return it to Amazon.