The second error, because you restarted the controller or turned off the machine caught the failure- you have a might have a ribbon cable failure. It's either partially unplugged or failing from flexing.
The first error message is one I have warned about. The ribbon cable breaks connection and is NOT immediately detected. If this happens when the current reported temp is just under the setpoint temp, then the mainboard is telling the heater to heat up faster to reach the setpoint. The problem is, again, the ribbon cable is NO longer sending current temp of the heater block back to the mainboard. This means the heater can heat the block well past the intended setpoint. Then the cable flexes from movement of the extruder head and makes contact again, sending the real current temp that is MUCH hotter than it should be and trips the safety code.
Check your ribbon cable connection and strongly suggest you either perform the safety mod or get on Raise 3D about the safety board being bundled in the not yet released filament detector kit. Even though the starting title says N1, this topic is applicable to all 3 models of printer.
viewtopic.php?f=4&t=6131&hilit=ribbon+cable Read all of it so you understand what is going on here.