Board is running code but not recognized by computers

My Metro Mini isn't showing up on any computers and I can't upload code.

What I've determined:

  • No messages in dmesg, no new /dev tty, nothing in lsusb.
  • The device is still running code on it. I was using it to control a bunch of external circuits and those are still functioning, so it must be running code on it.
  • When I plug in the Metro Mini the L light flashes like normal.
  • The board is a normal temperature.
  • I've spent a while reading forum posts and nothing matches my issue.
    What's going on? Is my board dead?

Was there any change or event that occurred between the last time the board was presenting a serial port and when you first noticed that it was not? For example: did you change the USB cable?

Yes, I was testing parts of my circuit/project by touching wires. I was really careful about touching the right things but maybe something shorted out on the arduino. I'd expect that the entire board would stop working instead of just the USB interface.

Make sure the USB cable is fully plugged into the board and the USB port on your computer.

Try an upload with no external components/modules/shields connected to your Mini.

Make sure the Mini is not sitting on any conductive objects (e.g., metal table, bits of wire, change) that could be shorting the contacts on the bottom of the board.