RE: Bed Thermistor - failing - MINTEMP BED - known issue?
Today, I encountered an error on my Prusa Mini for the first time. It had just finished a 2-hour print with no issues. After changing filaments and starting a new print, the error appeared immediately—very strange.
I decided to inspect the heatbed and removed the black plastic cover at the back (something I had never done before). To my surprise, I found that one of the thermistor cables was likely pinched from the factory by a screw, as seen in the pictures:
At first glance, nothing appeared broken. To be safe, I covered the exposed wire with electrical tape. Then, I measured the resistance at the thermistor connections and got 108 kΩ, which, according to the troubleshooting guide, is within the expected range.
I also checked the heatbed cables, and they measured 5.5 Ω—lower than the 6.5–7 Ω range specified in the guide. This makes me suspect that the heatbed itself may be faulty. Now I’m wondering: could the exposed thermistor cable have caused this issue?
It’s frustrating to find a factory defect like this, especially since I had never touched this part before. If you’re experiencing similar errors, it might be worth checking your thermistor and heatbed connections. Hopefully, this helps others avoid unnecessary troubleshooting!