Shorted fan, now Duet 2 Wifi is unresponsive

[TokeDK]

While fixing something my hotend, the parts cooling fan wires came loose and shorted somehow, I saw a small spark for a millisecond and afterwards the board was unresponsive and never connected to WiFi again.

I've tried following the guide here ("What to do if your Duet won't respond")

The DIAG light is constantly on, so is 3.3v, 5v and the light between reset and USB. I've not been able to reset or erase the firmware following the guide and the port doesn't show up on my MacBook (using SerialTools and Terminal).

I've completely disconnected the board from the 3D printer, checked the fuses and that the reset button isn't pressed in...

Is it dead? I read something about fixing a shorted fan somewhere on here?..

[dc42]

@tokedk does anything on the board get hot? Specifically, the WiFi module, SD card socket, main processor, or 3.3V regulator?

[TokeDK]

@dc42 Yes the main processor gets quite hot (probably 50c within 30 seconds) while the other components stay cool.

[Phaedrux]

That's not a good sign. It seems like you've shorted VIN to one of the lower voltage rails and shocked the CPU.

[TokeDK]

@phaedrux So the board is likely dead?

[Phaedrux]

If you're unable to get a bossa port to show up it's very likely dead. The hot CPU is a pretty good indication as well. If you're handy with hot air rework or know someone who is, you could possibly replace the CPU.

[TokeDK]

@phaedrux Thanks for the help. I've ordered a new Duet board, can't live without it