Thermistor issues after update
I have a MK3, been great for years, zero issue. I updated the firmware to the latest and tried to print something and it failed, Thermal Error, something like that, the alarm for it is insane btw. So I assumed that after all these years the thermistor had failed, I did the selftes thing and it stopped on the Heater/Thermistor not connected. So I replaced the thermistor. Before I bundled up the wires I did a self test and all was ok, passed every test. Bundled up the wires nice and neat like in the assembly instructions. Turn it on, self test fails. same message Heater/Thermistor not connected...
wires are all checked, took everything very carefully out and out it all back, read some post somewhere about a firmware issue and thermistors, but flashing back to previous firmware didn't do anything either. same message no matter what I do. I did the calibration thing for the hotend and it fails and said thermal error, once it said thermal runaway (but it hadn't even started to heat)
of course this was the first time anyone asked me to print them something, I was like sure, I can print anything...I was printing just fine till three days ago...
any help out there for the old MK3?
RE: Thermistor issues after update
nothing, nobody knows how to fix this...geez can someone from Prusa help?
RE: Thermistor issues after update
It's a little hard to tell what's going on from your description. Did it ever work with the new thermistor? Like when you ran the self test, did it heat all the way up without an error or was it just a test for electrical connection?
Have you tried reinstalling the firmware and factory resetting the machine, then rerunning the thermal model calibration? That's what they told me to do when I had a similar problem. If that doesn't work, try installing the old firmware and factory resetting the machine, and run the thermal model calibration again.
When that didn't work, the only thing that fixed it for me was replacing the EINSY Rambo board.
It's easy to short the thermistor or heater when cleaning the hotend with pliers so my guess is I caused minor electrical damage at some point and the new firmware somehow triggered the problem. Maybe by detecting the problem, but then I don't know why downgrading and resetting didn't fix it. Maybe the new firmware somehow pushed the boundaries of the electronics in a way that would normally be fine but turned the minor damage into permanent damage.
I hope you find a fix!
RE: Thermistor issues after update
I have the same issue… After the 3.14.0 update (or 3.14.1, I’m not sure now because I’m doing a calibration and don’t want to stop it), I’m experiencing the same problem. When I heat up the nozzle, it goes crazy at around 170°C–215°C, then starts screaming and displays “THERMAL ANOMALY.” I never had this problem before. I tried to contact Prusa, and they asked me to check the electronics with a multimeter. Unfortunately, I don’t have one. I also tried replacing the electronics in the extruder, but it didn’t help at all… same issue. I will try downgrading the firmware to see if it helps. The next step is probably a new RAMBo PCB, I guess… video with the problem... https://www.youtube.com/shorts/2JVy15ReCh8
RE: Thermistor issues after update
I had same thermistor error after the 3.14 update and replaced the thermistor just to find one of the power cables on the bed was cut half way through so i replaced that as well and no more thermistor error. Now I have a Y axis crash detected but all the tests are fine and prints the first layer calibration fine. Only when I try to print something else do i get a Y axis crash.
RE: Thermistor issues after update
I had same thermistor error after the 3.14 update and replaced the thermistor just to find one of the power cables on the bed was cut half way through so i replaced that as well and no more thermistor error. Now I have a Y axis crash detected but all the tests are fine and prints the first layer calibration fine. Only when I try to print something else do i get a Y axis crash.
RE: Thermistor issues after update
I just started getting the Thermal Anomaly and another thermal error (can't remember which) on my old i3 mk3s after upgrading to 3.14.1. Everything was perfect before that, on 3.9 or something. I've run all the calibrations, and everything passes, every time. But, when I go to print, it heats up to the necessary temperature, then throws the Thermal Anomaly error, and I'm stuck. I tried to reseat the hotend connections, but that didn't help. I finally tried preheating, then sending the print, and it seems to be working. I've started getting Y crashes, too, since the update, and fuzzy bits of filament sticking up in one place on both PLA and PETG prints (worse on PETG). Before the update, I'd never had trouble with either type of filament, in over 4 years of printing. When I disable Crash Detection, I don't get the fuzzies, and, if I don't get any thermal issues, it prints just fine. I wasted half a spool of Prusament PLA getting to this point, from non-recoverable thermal errors. I'm running smaller prints right now, to see how things go, before I tackle anything like the 65 hour monstrosity I promised a friend.
RE: Thermistor issues after update
Well, this is great. 20+ hours in, and I'm suddenly getting the Thermal Errors again. I've checked the stats in PrusaLink. The bed is +/- .3 degrees C, and the hotend is +/- .4 degrees C. It'll throw that error within a minute of resuming printing. (I have to shut if off, then turn it back on again to resume.) It does it every single time I resume. Always between 214.7 and 215.3 degrees C, for Prusament PLA. Since I can't send a gcode command to ignore this, I'm stuck abandoning this big print. I think it's ridiculous that PrusaLink and PrusaConnect don't have gcode terminal functionality.