duet 2 failure diagnosis

Shinomori

Hi,
I have a railcore with a duet 2 wifi, a duetx5, and paneldue 7i. I had a print failure last night that broke my BLTouch off the printer. The wires then touched and stuck to the hot end block melting all the wires. I don't see any other wires with any damage. The printer will not power back on even with the BLTouch disconnected. I get a blue light on the VIN light, but the screen doesn't turn on and I can't see the printer on the network. Clearly something is not right. All my fuses seem to be intact. Where would I start to diagnose what is wrong?

Thanks!

droftarts

@shinomori as BLTouch is supplied by 5V and has a couple of ground wires, I’d expect 5V has shorted to GND. Disconnect the BLTouch wiring from the Duet. If that doesn’t help, possibly the 5V regulator has failed. Take a good picture of the Duet board and post it here, so we can check for failed components.

Ian

Shinomori

@droftarts
Thanks.

I unplugged the bltouch and still nothing. Here is a picture with everything unplugged for a clear picture.
Drive link

Iterare

@shinomori

U3 in the bottom right that handles generating 5V looks fried. But it's hard to see if that's the only thing. good news is the the regulator producing 3.3V looks fine so the logic should be intact. Other components that U3 interacts with might also be shot(hard to tell from just the picture). you'll either have to de-solder and replace u3 (and maybe replace some of the others) and hope everything else is fine or try and source another board. Somebody else might know if you have any other options.

Shinomori

@iterare
Dang it! I was afraid of that.

Oh well. Time to save up for a new board.

I appreciate the insight. It's good to know how to proceed. Thanks

droftarts

@shinomori I'd think that U3 has taken the hit for the team, and is worth replacing. If you can't repair it yourself, and there's no one local, try the list of community repairers here: https://forum.duet3d.com/topic/13875/community-repairs

Ian