Random print failures, display shows "MINTEMP fixed", and "please restart"  

RE: Random print failures, display shows "MINTEMP fixed", and "please restart"

Posted by: @jeff-f5

I just got this yesterday on my MK3S. I had a fairly large print going, an 11 hour print that is a large circle that takes a lot of area. I checked it periodically, and somewhere around the the 7 hour mark it stopped, and had the Mintemp Fixed Please Restart error showing. I started the print again.

After about a couple hours, it stopped with the same error. At this point I Googled for information and saw talk about thermistors and wiring. I tried to wiggle the wires, but I could not get the reading to go to zero. They kept showing a steady measurement.

So I started the print again. Once again, after a couple hours, it stopped with the error again...in EXACTLY THE SAME SPOT of the print as the previous time.

So I'm really confused about what the issue is. How could it error at the same exact point of the print?

I have to correct myself...I just rechecked, tooke the heatbed off, and I see if I jiggle the thermistor wire, the reading goes zero. So, do I have to replace the whole thermistor?

RE: Random print failures, display shows "MINTEMP fixed", and "please restart"

@jeff-f5

Hi Jeff,  
I would replace the wire between the Thermistor and the einsy rambo, making soldered joints on the underside of the heatbed and inside the einsy rambo case so that the joinet are not on the section of cable that flexes. 

I would insulate the joints with heat shrink tubing or insulating tape so that the wires don't short to each other or to the printer components, and I would carry on using the printer, then I would obtain a replacement thermistor for use at a later time, so that i had one in stock. 
If you order from Prusa, the replacement thermistor usually comes with a piece of heat resistant 'Kapton'tape and a piece of aluminised tape to  secure the new thermistor to the heatbed

regards Joan

RE: Random print failures, display shows "MINTEMP fixed", and "please restart"

Thanks, I chatted with support afterwards. I decided to order a new thermistor and replace mine.

RE: Random print failures, display shows "MINTEMP fixed", and "please restart"

no problems Jeff, why not consider fitting the new part and repairing the old part for future spare, 
I would use wire like this for preference...

https://www.componentshop.co.uk/24awg-silicone-cable-wire.html

this is much more likely to survive repeated flexing!  note the Thermistor is not polarity conscious!

RE: Random print failures, display shows "MINTEMP fixed", and "please restart"

@joantabb

I actually ordered 2, one for a spare. 😉