Extruder Temp Fluctuating and MAXTEMP Error


My Wilson II printer has been rock solid for almost 2 years now, but lately the extruder temperature has been fluctuating while printing to the point where it gives a max temp error and stops. From reading other discussions I’m thinking a short in the thermistor wire is the most likely cause. I plan to try replacing the thermistor with a generic one from my old 3d printer, but wanted to see if anyone else had any advice to offer. Thanks in advance!


I wasn’t able to get the thermistor out of the heater block so I replaced the whole E3D V6 lite hot end with another I had from my old printer, but it’s still having the same problem. When I tell it to “PreHeat PLA” it fluctuates between 176 and 183 so I’m thinking there is still an issue. The power supply makes a buzzing noise when first turned on. I think it’s just a bearing, but I’m going to try replacing the power supply to make sure. Assuming that doesn’t fix it I will try replacing the Arduino shield. Anyone have any other ideas what it might be or how to go about narrowing down the problem? Thanks!


Tried replacing the hotend, power supply, and Arduino, but still had the same problem. I swapped out the PICA for a RAMPS and the extruder temp holds steady. Now I’m confident that the PICA board is bad. Not sure what to replace it with. Looks like the PICAs have been out of stock for a while.