I am having trouble with my MendelMax 1.5. Just this morning I turned it on and it smoked and then nothing. It even killed my laptop...DEAD!! I have looked around and I see that one of the stepper drivers is fried. Obvious burn spots on the chip. I replaced the stepper driver and turned the machine back on. The bed temp is reading 26 degrees centigrade. But, the extruder is reading 195 degrees centigrade, and is not turned on. It should be reading the ambient temperature of 26 degrees just like the bed is. I replaced the Mega 2560 and the ramps 1.4 with new ones and it is still showing 195 with the extruder. I then replaced the thermistor and it is still doing it. I have ordered 2 sets of cards and new stepper drivers just to confirm whether or not mine are any good. The Mega 2560 took programming with no problem, so that is probably ok. Also, the full lcd display is just lighting up, no text. I have made sure that the display is selected in the script for the arduino. I have set the thermistor to 5 and the hot bed to 80 in the table, this is what they should be. I am pretty much at my wits end trying to figure this one out. It really seems that it could only be the ramps board. Please, somebody give me some suggestions as to how to solve this problem. Being the ramps and the mega are the only two boards on the machine, it seems that one of these HAS to be bad. HELP!!!
Milt