I realize we don't have the same model, but it seems to be similar issues. Had a problem with the motor wires breaking, perhaps its that? I have a dual extruder and changed the wires from the second extruder, both at the motor and on the board to figure that out. Mine also appears to be a heat issue, although it reads the heat just fine. I haven't been able to figure out if it's a thermistor or if it's the heating element directly (have the latter on the way) but I'll find out by the end of next week.