So recently I upgraded my prusa I3 with a jhead from anycubic, the problem is the thermistor is reading atemp of 357 even when it is turned off. I have tried to get the right settings in the Marlin firmware by changing the temp_sensor in the configuration.h file but none of the settings worked. Can any one help me solve this problem? Do I need to create a new thermistor table, am I missing something obvious?