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Having trouble with the latest release of the firmware. On a V2 the temps keep flipping to "def" for no good reason. I can restart the machine, set the temps with the encoder, start a print off the SD card, and at some point soon after it starts printing the LCD reads "def' where the current temps should be and the heaters turn off. Can't restart the temp until a power cycle. Same happens if I heat and then try to do something like set the Z height. Also happens when printing (or doing much of anything) from the computer.

Def is cause by a thermistor interruption. One of the thermistors have either shorted (the wires touched each other) or temporarily lost connection somewhere. Check the wiring. It is not a firmware issue. The firmware just shuts down the heaters when the fault is triggered to prevent a runaway over heat.

I think this could be caused by default values in the firmware that do not take your specific setup into account. When you start the machine, what are the temps without starting any heater? Does that show some "real life" values? Like 20C for ambient temp? And if you start a heater, does the temp rise in the display? (try one by one). I think there is a safety measure in place, that if a temp does not rise within a few seconds after starting a heater, the system shuts down DEF. That would happen if you start the wrong heater because it is not configured right in your firmware (or connected differently than in a default machine).

DeltaCon wrote:I think this could be caused by default values in the firmware that do not take your specific setup into account. When you start the machine, what are the temps without starting any heater? Does that show some "real life" values? Like 20C for ambient temp? And if you start a heater, does the temp rise in the display? (try one by one). I think there is a safety measure in place, that if a temp does not rise within a few seconds after starting a heater, the system shuts down DEF. That would happen if you start the wrong heater because it is not configured right in your firmware (or connected differently than in a default machine).

Perhaps you are getting confused with a dec (decoupled) error.

joe wrote:Def is cause by a thermistor interruption. One of the thermistors have either shorted (the wires touched each other) or temporarily lost connection somewhere. Check the wiring. It is not a firmware issue. The firmware just shuts down the heaters when the fault is triggered to prevent a runaway over heat.

You were right. It is something physical, not software. Not sure what yet, but I was able to replicate the error by just fiddling with the wiring harness. it was just coincidental that I encountered the problem at the same time I changed the firmware. Thanks for the assist.