Failed firmware upgrade - can't revert  

New Member

I have a MK3S which I recently attempted to upgrade with the MMU2S kit. After completing assembly, I attempted to upgrade the firmware (Prusaslicer 2.2.0 on Ubuntu, also tried Windows 7). The flash went just fine to approximately 50% (100% written and 100% verified according to the display on the LCD) and then fails, with the "External SPI flash W25X20CL not responding" error. This error now presents every time I start up the printer. I have attempted to re-flash with various other windows and Linux machines, always failing at the same point. I have found this article and attempted to flash with the LCD cables disconnected with no difference in outcome. I have also attempted the factory reset procedure to bring back my MK3S firmware and try from a blank slate, however that instantly produces the aforementioned error.

I have gone over every troubleshooting step I can find, the printer is an MK3S that was ordered in May and was working quite well before this firmware attempt. Are there any other troubleshooting steps to try?


Posted : 14/09/2020 10:38 pm
Eminent Member

Sounds like your printer would still be under warranty, best contact Prusa and see if you can get a replacement board
Posted : 21/09/2020 12:18 pm
Noble Member

This means your flash chip (where languages are stored) may not be working. If not under warranty and/or you can live with English only, you can ignore it and continue using the printer. 

If under warranty, contact PR and they will probably replace the board.

Posted : 21/09/2020 2:27 pm

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