Need help getting old printer running again
I will try to keep this concise as my issue is probably lengthy to describe.
Purchased new I3 MK3/S when old i3 MK2/S began giving me some problems. The new MK3/S is wonderful!
Everything was fine with the old printer until it recommended updating the firmware. I couldn't find the precise firmware for the MK2/S, so I went with what seemed like the closest thing which was the update for an MK2.5. In hindsight this was obviously the wrong thing to do. Once installed, my old printer gives an error message when I try to configure or start a print. It indicates the hot end left fan is not installed correctly. This is wrong since nothing has changed and the fan spins fine. I communicated with Prusa and followed the directions in the links to ensure there were no connection issues. Believing that my problems were possibly associated with my installing the wrong firmware, I followed the process for restoring the default settings. However, even after doing this, my display still shows the firmware version as MK2.5. As I research this more, I see that the fan(s) in my printer are different that what is used in the later models. Specifically, my fans have only two leads (black/red) and the later machines have three. I have a theory that the fans with three leads allow the later firmware versions check the fan speed. If my MK2.5 firmware is looking for a three lead fan (which doesn't exist in my printer), maybe that is the reason for the error message? Also, when I went through the process of restoring the defaults, why does the display still show the printer running MK2.5?
Any help would be greatly appreciated.
RE: Need help getting old printer running again
for the MK2.5s it montiors the fan speed, and since you don't have the correct fan (the fan would have an extra yellow wire for the RPM sensor) it will pop up that error. Now you have 2 options. You mentioned that you had issues with updating the firmware, are you using the 13a version from this?
https://www.prusa3d.com/downloads/firmware/prusa3d_fw_3_2_3_MK2_MK2MMU.zip
You can reflash the firmware and then do a factory reset to clear the board, but this will also clear your first layer setting, so you might want to write it down if you already set it. You can reset the printer by following this guide.
https://help.prusa3d.com/article/factory-reset-mk2s-mk2-5s-mk3s_2216
If it will not downgrade, the other option is to go into the settings in the printer and turn off the fan sensor in the settings. If you scroll down in the list you should see "fan monitor" and switch that off.
Shane (AKA FromPrusa)
RE: Need help getting old printer running again
Same Old Shane,
Your information has been extremely helpful. I have made great progress toward getting my MK2/S running again. Specifically, I was able to flash to the older firmware that seems appropriate for my printer. The fans now indicate OK during the self check. I have been working with the calibrations, but it seems that after every problem that is solved, a new one arises. I finally got to the point of printing an object that I have printed before. Even though I have printed this object successfully from an SD in the past, I now get the message that the file is incomplete. Any more wisdom to help me through this?