I’ve seen a number of threads on this issue, but have never seen a resolution. I have 5 A1s, and 3 A1 Mini’s, all with AMS Lite. Most of the A1Ms have over 5K hours, most of the A1s have over 2500 hrs.
All but two new A1’s have at least 1 slot of the AMS that will not work, and will always throw a “Filament Failure to Feed” error. If I run a single color print, that slot will work. If I do multi-color, that slot will not work or will “fail to feed” every single color change. Happens with PLA, PETG, PLA Silk, PLA Pro.
I have tried everything. New PTFE tubes. New extruder, new filament sensor, new hotend. PTFE support brackers from makersworld. Turned off tangle detection. Tried all of these at once so nearly everything was brand new, still same problem. This is not a “jammed filament” or “filament is the wrong size” or “maybe the AMS Is too far from the A1 and you need to move it closer” kind of problem.
This is obviously an AMS problem. And a chronic problem. And is repeated across almost every single A1 I own. Is this a circuit board problem in AMS? Is this a mechanics issue? What parts need to be replaced? Do I need a new AMS all together? It’s extremely frustrating to have all these A1’s with AMS’s and all but 2 can’t be used with 4 colors. One of them only has two slots working. I have not engaged Bambu support yet, mainly because it takes weeks and weeks to get any progress with all the back and forth.
This sounds like a warranty issue. My son and I just hooked us his new Christmas toy - AMS lite to his a1m and we got this error on slot 2 on the second, yes second ever print with the AMS lite. It was great until it didn’t work major disappointment
It’s absolutely a warranty issue. However… If you’ve ever dealt with Bambu support, you’d understand why i haven’t bothered engaging. It’s weeks and weeks of back and forth of “did you plug the machine in” (wait 2-3 days for a response), “okay, is it powered on” (wait 2-3 days for a response). They are friendly and eventually get to solving the issue, but its too slow of a process. Compound that by having issues with 6 machines, so that’s 6 different tickets.
Went ahead and submitted 6 warranty claims. As expected, the demands and requirements from Bambu to support the failed hardware is absolutely ridiculous. Multiple videos, proof of what i use and how i use it, etc. Absolute insanity.. I spent over $2K in the Bambu store in 2025 on replacement parts, which I should have done claims for, but because of how poorly they run their support structure it just makes more sense to eat it. This will be no different i’m afraid, however its a $69 part to fix it, times 6.
Quick update. These components only have a 3 month warranty. Bambu will not be covering any of these defective parts.
Support tells me that these components wear out due to “variations in filament diameters”. They recommend taking the entire feeding units apart and stripping them down and cleaning each part individually every 2-3 spools of filament that go through them. If you’ve never done this tear down, it is extremely tedious and very challenging to reassemble correctly.
Almost $500 to fix my 6 printers. Looks like I will begin to shop other brands for my next printer purchases.
Let me put it this way: depending on your country of residence, you could, of course, take the next step. More precisely, it also depends on which payment service provider you used. Have the money paid for the AMS order frozen retroactively. This means that no one will be able to access the money until the case has been resolved.
However, it is impossible to give a general recommendation because it depends so much on which country you live in and which payment service provider you use. Nevertheless, something like this often achieves great results.
The question is whether you want to put yourself through the stress. Also, in most cases, it is then no longer possible to do business with the company afterwards.
Just as an example, such a regulation from Bambu is invalid in the EU. (legal guarantee)
Did you pay via PayPal? That could be a possibility. You have 180 days to do so. It varies from case to case, but PayPal does sometimes take action. It would be worth finding, though. As I said, this is just a suggestion. You would first need to check whether PayPal would accept the case at all.
Credit card companies such as Visa and Mastercard also offer this service in some cases, but mainly in cases of actual fraud, and you would have to submit a request first.
I have one A1 with an AMS Lite. I power the A1 off when I’m not using it. When I power the unit on and send a job from Bambu Studio or Bambu Handy, the first print on any given spool (1, 2, 3, OR 4) will fail with “Unable to feed filament into the extruder.”
The solve has been to wind the spool back and remove the filament completely from the AMS Lite, snip off a few inches of filament, and push it back in until the AMS Lite grabs it. Usually at that point, but not always, the print will resume and that spool will not have any more trouble… until the next time I power the printer off and back on.
Today I stumbled onto an easier fix for the feed problem. I noticed that the AMS Lite will grab the filament and push for the first inches or feet or however long it takes until the filament reaches the end of the PTFE tube where the four tubes enter the extruder assembly. This is where the filament visibly stops and the AMS Lite retracts and feeds a few times before declaring that it can’t feed. Out of mild desperation to restart a print without snipping and re-feeding filament, I grabbed the springy plastic piece between the bottom of the four bowden tubes and the extruder gear, and gently pushed it straight down until the spring was fully compressed and nothing was “floating” up in the air - see photo. With the rectangular plastic piece held down, presumably shortening the path for the filament to reach the extruder gear, I hit the resume button on the A1’s screen. The filament grabbed without a problem and my print began!
TLDR: I think the joint where our four bowden tubes connect to the extruder is the culprit. Pushing it down and having the A1 continue a print seems to work. Can’t hurt to try it!
It seems I cannot add a photo directly to this post, and I can’t include actual links, so please paste this link into your browser and remove the two spaces I added in order to see a photo of what I’m trying to describe:
Bambu didn’t want me to start a new similar topic. I bought another A1 combo in November 2025. It has never worked. It prints fine but it can’t load filament without me physically pushing it.
It’s “snagging” on something between the hub and the extruder. I can feel it when I manually push filament in. The AMS tries a few times then errors out.
Also, I can’t get the hub off. All my other A1 and A1 minis, I just pry on the right side and the hub pops off. With this one the right side comes up but the left side is still firmly attached and I don’t want to break it.
I opened a ticket and sent a photo that clearly shows my AMS Lite is mounted on top of the machine with Bambu’s own mount design. Support replied that the AMS is too far away from the printer and that’s why the hub is leaning to the right. I guess they didn’t look at the photo.
Then they closed the ticket and called it Resolved.
I can’t print multicolor unless I help it load every filament change. That’s not feasible. I wonder if anyone has had this issue and resolved it. I turned off the Tangle Detection but that doesn’t help because it doesn’t have enough force to push past whatever is blocking it.
May I ask a silly question? Why not do the obvious: Request to return the device? Freeze the payment?
I mean, it’s not always necessary to bring out the big guns, but if you delay for too long, you’ll miss your opportunity. I mean, if you bought a new car that turned out to be broken, you wouldn’t just say, ‘Oh well, I’ll wait and see.’ There’s no need to escalate things, though I would apply a little more pressure.
As mentioned, if that’s the case that the device never worked and it is not a user error.
It’s a good start that you’re asking in the forum.
Cant speak to most of the rest but this is my experience as well, the newest revision of the A1 ships with a hub VERY firmly attached. It has me a little worried too. Try to get it off though, because your issue lies underneath almost certainly.
Yeah, I didn’t want to say that I’m thinking of disputing the charge. It took Bambu Support several weeks just to come back with an absurd answer. I had another ticket open on my P1S and they kept sending responses that were in no way relevant to the issue. LOL.
Any clue why I can’t get the hub out? It might be as simple as a piece of filament but I can’t get it off.
Edit: It came off. Felt like it was glued on the left side so i just went for it.
The hub is clear. I started a print. It made it to the extruder but on the third try, so the problem isn’t solved.
Same problem, although I carefully pried off the top, sliding the tweezer around it. It was not an easy pop off like bambu video. I added the AMS Lite last night and only one color would work. Thinking there was a clog I removed the hot end and nozzle and cleaned everything well. No change. Now I’m unable to pull out ANY of the tubes which I think is caused by the “teeth washers” inside that grip the tubes. Can’t push the tubes through, either, they are stuck. Did not have this problem with the single spool – which now can’t used used either. It’s dead in the water now until I figure out how to get the tubes out. Sigh.
I just got a A1 / AMS Lite combo in January and now having this issue as well in the last 2 days. My A2 slot keeps saying failure to feed. Sounds like I’m having the same issue.
I was wondering since it’s only happening in multicolor prints if it’s software related. Because when I check the filament during the error, it moves freely, and when I hit resume - the printer doesn’t attempt to do anything and the AMS motors aren’t even attempting to push filament to the extruder for another try.
major disappointment