A2L AMS Lite frequently complaining about stuck filament

I have an A2L that is 2 days out of the box. I’ve made about 5 prints with it so far, and in the last two I have run into an issue with the AMS Lite. About every 1-2 hours it complains that the filement in position 1 is stuck and pauses. In every case so far (5-6 times), the filament is free and clear and all I have to do to resolve the issue is to click the button that says “Resolved (continue…)” and it starts back up. But this means that the print that was supposed to take 16 hours is now set to complete over 24 hours after it started. I can’t be babysitting this printer constantly. My other two printers don’t have this problem.

Is there a tweakable parameter as to how “stuck” it needs to think it is before it pauses and asks for help?

I just realized while watching it, that it frequently “swaps” the filament (unload and reloads), even though it is a single color print and isn’t actually swapping the filement, just unloading the reloading the same filament.

If the AMS was working fine before and is now causing problems, I’d start by checking to see if your setup is correct:

  • Are the tubes really inserted all the way? This is one of the most common problems.
  • Make sure the tubes are cut straight, not at an angle.
  • The tubes are different lengths; make sure you’ve placed them correctly.
  • The bending radius of the tubes shouldn’t be too sharp; make sure they’re laid out properly.
  • If you used old tubes instead of new ones.

Only then would I continue with troubleshooting.

I’ve solved the problem, but am still not 100% sure what the root cause is. The spool that it was printing from (in slot 1) was nearly empty, and that was somehow causing it to think it was jammed. Swapping to a fresh spool made the problem go away, as well as the filament swapping behavior I guessed was related.

As for other issues: The tubes are just as they came out of the box, already bundled and cut to length, and were all inserted fully. None of the other spools is displaying this behavior, so I’m going to assume there’s some quirk with that nearly empty one

My A2L w/ AMS Lite is only about a week+ now and it’s been exhibiting the same quirks. 2 or 3 spools now (2 BBL, 1 FF). The tension required to set off this alarm must be pretty light cuz I’ve done the wiki troubleshooting for this error. Restart has worked a couple times without issues for awhile. I’ve also UNSPOOLED numerous feet & rolled back up (way worse looking IMA) and it runs fine until all that’s used & starts working down into factory layers of wind for a bit Have also done following other things to help:

Bought a Sunlu S4 dryer, got Bag Shield bags & vac + silica bags.

Like to know if others are having similar issues & anything that helps.

Thx ALL!!

I’ve been having the same proplem it keeps bugging out for no reason every 4-6 min even tho my spool is perfectly fine it still have 200 to 225 g left I bought a 250g one and it just won’t stop help me

Please provide a little more information.

First of all: Which adapter or spool do you use for the 250g filament? And from which company? AMS Lite, 250g only work with an adapter, depending on the manufacturer.


You’re also welcome to post a photo. You can’t do that yet because the system hasn’t classified you as a basic user, but it won’t take long: Spend 10 minutes on the forum, read a few threads and comments.

Do u have any other app we can talk on also it’s ams lite i just finished my butter fly knife but it tried to suck the spool then return it then when i click procced without doing anything it just starts normal

I don’t use any other app.


However, if English isn’t your favorite language, you could try using this tool or visit the international section of the forum:



No it’s ok but tomorrow I will try to make smh cuz I’m trying to like start learning it and this is my first 3d printer and I would like to know how to fix it

I have the same issue. With Sunlu PLA spools, when the filament gets near the end (about 100–150 g remaining), my A2L throws so many stuck filament alarms. It happens with every single spool, and it’s really annoying. I think the firmware needs to be updated, or the sensitivity needs to be adjustable by the user.

Filaments near end-of-spool are winded sharply bended so there’s more friction/drag induced on the whole filament path. Basically, check if your setup is creating conditions for anything less than the easiest path for bent filaments to reach the toolhead.

The AMS Lite has always had flaws here since A1 days esp. with the funnel placement not centered against the roll (and it not being motorized during printing), but most filaments should’ve been fine. It was particularly more notable for hard filaments like Bambu PLA-CF, Bambu PETG-CF(banned since), plus Bambu PETG Translucent of all things.