I have 1xP1P, 1xP1S and 4xX1C all with AMS. I print 24/7 PETG from Aurapol (Same base material as Prusament).
Yesterday I had 4 different AMS units with a faulty filament sensor (when you remove the spool, the AMS stay white). I had 1 filament sensor dying few months ago and I changed it without issue, but 4 in the same day on 4 different AMS (All Printer/AMS have been baught in few weeks appart so it should not be a batch problem)… Pretty strange.
I tried to blow air in the hole, and poke arround with some filament but no luck, I will replace them.
Could be from filament yes, however it is likely due more to the tension on the extruder being to high. The sensor is just a hall sensor which is a microswitch with is subjected to clogging, gumming and the like.
I changed all the feeding part and sensors that where faulty and problem came back.
First I switched to eSUN PETG for few weeks: no issues at all. Then I went back to Aurapol PETG as I love its look (I print about 60kg / month) and ALL AMS slots (24 in total !!!) have the filament sensor issue (staying White when no filament).
I try to understand what is the issue and why it is only with Aurapol PETG. I tried a different Aurapol PETG color but same issue…
Does someone has an idea what could be the root cause of that ?
When you replaced all the sensors did you find broken filament in all/any of them? If you still have the ones you took out I would inspect them very closely and see if there is broken filament in there. My best guess is the Aurapol PETG has gotten damp and brittle and is breaking off right where the sensor is. Statistically I think you’d have a better chance of winning the lottery TWICE than 24 filament sensors all failing at the same time.
I have inspected all the filament sensor and they look SPOTLESS. I see visible mark on the rotating metal piece, but the rest of it is very clean.
However, inside the feeding mechanism there is a loot of some kind of goo, it looks like a kind of gel mixed with particules… I will take detailled pictures next time I change one, I have 7 sensor left to change.
I think the answer is obvious. The filament is the cause. Why is the next question. The AMS is trying to tell you that it isn’t fond of that filament brand.
I am struggling with the same issue. 3 AMS and 6 dead sensors with white lights stuck on. I print a lot of clear PETG (Bambu or Sunlu) as well as black PETG of the same brands. 99% plastic spools so a tiny bit of cardboard ones. I’ve taken one AMS completely apart, blown air, looks for clogs, switched which ports they are connected to without success.
OP, did you manage to clean off the goo and fix the sensor? I will take one down to the individual parts today I guess.
