I am using simplify3d and have been printing successfully for several weeks. Today my printer stopped mid-print due to a max temp error. I looked at the temperature plot an there was a huge spike out of no where. My thermister does not appear damaged. Any clue as to whats happening? Now when I go to print the error occurs before the skirt is even finished. Everything was purchased from vicious by the way. Thanks in advance!
If you have not changed anything in the firmware (in terms of thermal runaway or thermistor settings, probably a damaged thermistor wire or it’s connection to RAMPS.I always have spare thermistor and hot end cartridges in times like this 
Well if I am going to have to replace the thermister and hot end should I look for an upgrade? Does anyone have experience with the E3d V6 hotend? It would be nice to mess around with the exotic materials.
It sounds like your thermistor wire might have broken somewhere. Check the resistance, if it is 0 then the wire broke, it should be near 100kohm. Should be a simple fix. If the thermistor did die, they are about $1 to replace.
yep, thermistors in Amazon are dime a dozen.