Thanks for the GCode, i did try it in different print but its still doing a random layer shift in one of the pause (i print more than 2 colors these days). I tried different technique while changing filament (via machine or studio or waiting longer or even not changing the color at the pause) but yeah, Bambu need to fix their software i guess.
Obviously, they might not care too much here with manual color change during a pause since they sell the AMS which doesnt have layer shift 
Turns out my loading problem was manuel AND software 
First, I need to hold the filament IN (pushing a little) until the machine reach 250 degrees or it won’t “grab” on it.
THEN, i need to have my APP (iOS) open on the filament tab while doing the LOAD and tap the DONE button when its loaded or it wont Resume the print (after clicking resume on the printer)… at least thats what i need to do on my side. So, yeah, a bit of time waste when printing a lot of models with 3-4 color layers like im doing right now
I still do have the money for the AMS yet…
I am the proud owner of an AMS and use it in the Backup Mode (Spool failover) not for color change and guess what happend every time it changed the spool? Yes , Layer shift. I will now check the points discussed here. I had the new option “step loss recovery” not activated. I will now check the points discussed here. Very useful for a beginner like me
Thanks for the info! If you can test that, it would be great!
I borrowed an AMS yesterday so I’ll test it with Color Change this weekend too
6 Failovers are spot on (no layer stifts) after new option “step loss recovery” enabled. When it happend there might have been a mechanical problem as the possible source, blocking spools in the AMS. The transportsystem of the AMS must have a good grip on the rim of the spools (the rim must be FLAT and no sharp brims from the moulding of the spool, sharp edges will ruin the rubber rollers over time) and MUST NOT wobble. The spools I used when it happend woble so much that they occasionally block the AMS. When the filament is pulled tight, over time the outer sides of the spool started bending out and occasionally blocked in the AMS. Bambu mentiones to use their spools, but i did not realise its implication. Good solid Spools and the AMS is really your friend and willing helper .
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Nice!
I’ll test the Recovery Option and make sure to check the spools for the AMS. Im kinda surprise about the “rolling system” for the AMS since it cost quite a lot imo and a lot of people are saying that its not the best and can easily block.
I’m having this problem. Turning on step recovery didn’t help. I know this is an old thread, but was a solution found?
For me it was solved with the firmware version 1.03.x. The layer shift because of the firmware error was around 1 mm. I could estimate the size of yours, but seems to be more than 1 mm. So I think it’s another problem.
Mine was solved suddenly
Hy everyone. Does the problem have been solved ? I have the same problem but an calibration does not work.
i am having the same issue no matter what i do. it has ruined so many prints.
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Im having the same Issue, the Layershift only happens on the first color change, consquent ones don’t cause a shift.
I see the issue is coming back.
Don’t had it anymore when enabling “recovery from step loss” in the options
My problem is solved. Support contacted me. Please check the 4 screws on the back that are used to tension the belt.
I had 2 screws loose on the right side !!!.
Follow the steps in this guide and the problem should be solved!!
The 4 screws do NOT be loose !!!
On mine the issue was ptfe tubes worn through.
PTFE tubes: good comment, when I gradually get more visible layers I check all the tubes these days and usually they need replacing. This has probably also prevented the shifting layers in the recent past. I think in my cases the initial cause was friction in the tubes or filaments getting stuck during spooling. The filaments I use often have a severely bent or jammed end of the filament in the spool and the head jerks when the filament is pulled out of the empty spool. I now also cut the end of the filament as close to the spool as possible to prevent the head from jerking during failover. I believe that in my layershift problems in the past it was always a mechanical obstruction to the filament flow, as the individual layer visibility usually had increased some time before it happened.
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I had originally had the same issue and tried everything as stated above. Then I had found with my stock P1P that the PTFE tube was both worn as well as the attachment point to the head cable were not equal.
When my head would go back to purge position the hose/cable system would bind and start my print offset. Once the PTFE tube was changed and the hose/Cable balanced out everything printed correctly.
With the PTFE tubes being very affordable and easy to replace it’s a no brainer to replace these when you notice them starting to wear.
I just had this issue and my PTFE tubes are just fine… These printers just suck at resuming like every other printer does when it comes to starting after a pause
before reading and hoping to find a solution I just want to say I thought I was doing something wrong causing the layer shift and now see this is a known problem, at least I hope so. I also cant even think about the amount of filament I have thrown in the garbage because of this problem. My one color prints are absolutely flawless so there is something wrong with the color change, first color, first level. Wonder if there is a shift change when second color, first level? etc?
I’ve only had my P1S since December and been seeing a shift in the X-Y axis when the printer is paused and resumed.
But on 2 occasions, I had an even worse effect: Once when at the beginning of the print, the head moved from front right to the rubbing area and the nozzle was too low so it scratched the whole plate (totally new).
And then it even did the whole rubbing ON the plate itself instead of the back!!!
I have to say that I am very disappointed… I opened a ticket 10 days ago and still no answer.
When I got the printer, I ran out of filament, so I changed and continued and it was perfect. I then made an update (don’t remember what the previous one was) and started seeing these weird behaviors. Currently have the latest: 01.05.02.00 (latest version).
Also checked the screw at the back, they are tight, PTFE tube moves freely and “Auto-recovery from step loss” has no influence…