Printing along fine, and suddenly I get extruder failed to feed errors.
Cleaned out the extruder, still failed. Ordered a new extruder, complete, plugged it in, still fails to load. 0700-8007-143301 error. Changed out the head, still fails.
I can see the filament go into the extruder. The extruder “filament present” indicator lights up. Printer retracts filament. it does this 3 times and fails.
I’m very frustrated. HELP PLEASE!
Look in the buffer, rotate the magnet that’s in it.
Could it be the filament sensor in the print head? I did not experience it myslef but remember that a broken filament sensor is/was difficult to troubleshoot.
When feeding filament manually, does the Filament indicator in Studio, Bambu Handy show a loaded filamemt? If not, it is likely the sensor.
The sensor was replaced with the extruder assembly, it all comes as one.
Buffer? Magnet? Could you expound on your idea sir?
Also yes, I see it when auto-fed and manual fed. The filament indicator comes on.
are you using an ams?
if not disregard
If so the buffer is the little box that the ptfe tube from the AMS goes into, and is connected out to the print head.
Inside is a hall sensor. It is a magnetic sensor. reports have it that if you rotate the magnet it can solve your issue. The magnet is in the “plunger” looking end of the spring thats visible.
So it is not the filament sensor. But @johnfcooley seems to have nailed it (as always 
):
Not always, just with coffee.
I so relate to that sentiment
Magnet rotated. Nada.
If I pull off the AMS feed tube from the head as I do a load filament, it trips the sensor, the head pulls a piece of loose filament in, and then shoves it back out.
So you are using an AMS.
How are your PTFE tubes? How long have you had it and have you ever replaced any?
I replaced the PFTE tube from the head to the AMS unit today, thinking that may be it. Nope.
There are 5 more. They wear out too.
Mhm. Just checked further issues with that error and remebered the trouble I had when I did not cut the PTFE ends perfectly straight and sharp or failed to push them in fully. I can’t remember the error message I had though. Fortunately though, it is an easy check (unless it is the PTFE’s in the AMS but then I’d expect a single position to be affected first).
Another user reported the spring in the buffer being bent/caught can also result in this error.
There are a few more troubles with the AMS that I experienced, but they usually result in a motor overload error. Except maybe filament being caught in the AMS switch itself. Can’t remember the error message though.
I’ve had this error, always was PTFE related, or the one time I had a sliver of filament stuck in the top of the extruder. OP has swapped so isn’t that. Goes all the way then pulls back. Seems like it feels too much resistance. Worn PTFE can cause that as well. I swap mine inside the AMS about every 6 months. More if I decide to run GF through it.
Well, it just suddenly works. Maybe something was hung up in the AMS, but it doesn’t explain why it wouldn’t take a 10’ chunk of filament I was feeding by hand at the extruder head.
Anyway, seems that I am operational at the moment.
Posititve thougths saved the day. I was OOOOHHHHMMMMing in your direction.
Glad it’s working.