Been dealing with a problem with my 3d printer, the Prusa i3MK3s that I have been running for the last couple of years. Up until recently, it has been running very well – solid prints, reliable operation, no major issues. In recent months, I did have an issue with bed adhesion to the removable build plate, but that was resolved with a surface treatment.
However, as of last week, I started having a new issue. The printer starts correctly, calibrates the level, and then starts printing. Everything runs fine, until the end of the first layer, at which point the printer immediately freezes with a “printer crash” – even though nothing is there. After a bit of screen flickering, it then changes to a “TMC driver overtemp” error and forces a reboot. As a result, I have been unable to successfully print anything for several days.
Initially, I thought (due to the screen flicker) it was a power issue, perhaps the outlet or surge protector wasn’t providing enough power. I had relocated the printer before the error started, so hoped that was all it was. However, once I moved it back, the problem continued. Next thought was that perhaps a wire got caught/cut/broken during a recent filament clog clearing. When filament gets stuck in the extruder, I tend to have to disassemble the extruder module, and some of the wires are rather awkwardly placed, tending to be pinched between pieces.
That doesn’t appear to be the case however, since when I disassembled the extruder assembly again, and ultimately ran a full self-test on the printer, it came up with a failure on the bed surface fan – on closer inspection I found that one of the wires to the fan had broken. As a result, I am now waiting for replacement parts, and then will have to deal with the re-installation of that fan. Not a pleasant prospect, since it run along the cable bundle all the way back to the main control board and requires removing quite a few screws and ties.
Hopefully, this is the overall cause of the issue – a simple short circuit due to the broken wire. This may also explain my occasional issue with “Temperature Overrun” errors, which seem to randomly affect my prints. Ongoing theory here is a problem with the bed heater coming loose or disconnected, but it is possible it was just the fan failing a while ago.
Repairs should be underway tonight, will update if that resolves the issue – or if a new one is then discovered.
