Hello everyone,
I’ve been using my X1C for quite a while now — I’m currently at around 3250 hours of printing, and I just finished a big one-month production run for a client (about thirty spools of PLA, printing almost 24/7). For the past week, I’ve been regularly getting the HMS_0700-4500-0002-0003 error message related to the filament cutter being blocked. It shows up before every print.
When I manually move the small lever on the side of the print head, it’s not actually stuck, but it feels like doing that “resets” the sensor, and after that the print starts without any issue.
About ten days ago, I fully disassembled the extruder to clean it thoroughly, same for the lever magnet, so it’s definitely not a dirt or debris issue — and the error was already happening before that maintenance. Another thing: it seems to only happen when I use Bambu PLA. If I use another brand, like Machine3D, I don’t get any errors. Also, when I reboot the printer, the error goes away… until I run several prints back-to-back; usually by the third or fourth print, it comes back.
I’m considering replacing the lever with a new one. I also wanted to replace the hall sensor, but it’s not sold separately on Bambu’s website — you have to buy the whole extrusion module. Before doing that, I wanted to check whether anyone else has faced the same issue, and what solution worked for you.
Thanks in advance.
How does the cutter blade look? If it gets dull it can cause issues. That’s the first thing I would replace.
The sensor is actually in the filament sensor and that would be my next step. It has the sensor in it that tells the printer if the cutter arm is depressed:
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I’ve replaced the filament cutter, so we’ll see how it goes.
I also cleaned the lever magnet again (it was dirty), and honestly I don’t understand how the extruder gear gets dirty so fast.
I’m starting to think my belts might be wearing out.
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Well, it’s not working.
I’m trying to dry a filament and the printer keeps pausing because of this “cutter blocked” issue, even though there’s nothing in the extruder or the AMS…
I’ve ordered a new sensor, so we’ll see how it goes.
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Last update for tonight: I rebooted the printer and loaded a Machine3D filament directly into the extruder, then restarted the drying cycle… and now it works.
I honestly don’t understand anything anymore 
After ordering a new sensor, a new cutter, taking everything apart and cleaning it all a second time, I still have the exact same problem…
It’s clearly not a sensor issue anymore since it’s brand new, and it’s not a dirt issue because everything is spotless.
It might be the connection to the extruder board, but if I replace that and the problem is still there, I might as well throw the printer away and buy a new one…
Thanks Bambu. I’m going to open a ticket, but just a heads-up for new buyers: after around 3000 hours of printing, there’s no guarantee the machine will keep working properly.
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I have the exact same issue on the same printer, also 3,300 hours