Prusa MK4 + MMU3 – “Head heater thermistor wiring damage” error after firmware update
Subject: Prusa MK4 + MMU3 – “Head heater thermistor wiring damage” error after firmware update
Hello,
I have a problem with my Prusa MK4 and MMU3. After updating the firmware to version 6.2.6 (MMU 3.0.3), I started getting the following error when changing filament:
Head heater thermistor wiring damage
I have checked all cables and connections — everything is fine. The printer works perfectly when printing with one filament.
The issue only happens during filament change. When the MMU changes filament, the nozzle temperature first goes to 205 °C, then up to 220 °C, and at that moment the error appears. The temperature quickly drops to around 213–215 °C, just before loading the new filament.
It looks like the printer detects a temperature spike during filament change and triggers a false “thermistor wiring damage” error.
How can I fix this issue? It only started after the firmware update. Before that, everything worked fine with multi-material printing.i try downgrate but allso not helsp now its broken on first change :/pleas helsp
Hi You can see on video when it's stopped, one layer mmu3 working but on second get error. Please help I think it's error by software like you see , I don't know why temperature on second go 200 ten immediately go too 220 but heater give grow. Meeting time printer stopped. I waited for your help.