Fixing, recycling or repurposing a damaged Arduino

I have a damaged Arduino Uno (I suspect I did something stupid like trying to drive a DC motor from it): it is detected when I connect it to the computer but I cannot push anything to it (programmer is not responding) and it fails the loopback test. According to the support docs,, "If it [loopback test] fails, your board is damaged beyond economical repair and should be replaced."

I am curious if there is any way of fixing, recycling or repurposing either the full board or some of its components - I don't like things going to waste. I have a bunch of other working boards (two Uno R3s, as well as some Raspberry Pis and ESP32).

If anything, I'd be happy to do a surface soldering exercise, especially if it's something like a voltage regulator.

What have people done with their damaged Arduinos and are there any tips for going beyond the loopback test to diagnose the problem?

  1. How is your board recognised? As an Uno or as a 'generic' serial device?
  2. Be aware the the loopback test does not seem to work with clones that don't have the 16U2 TTL-to-USB converter; so that test might not be the holy grail.
  3. If the board has the DIP version of the 328P, you can remove it and run the loopback test again.
  4. With the 328P removed, use an external power supply (7V to 12V) connected to Vin and test the 5V output
  5. If (3) passes, you can either use the board as a TTL-to-USB.
  6. If (3) and (4) are OK, you can buy a new 328P, insert it and burn the bootloader.
  1. The board is recognized as Uno: Arduino Uno, VID: 2341, PID: 0043, SN: 55834323933351A012A2

  2. How do I know if it's a clone or proper Arduino? Here is the picture:

  1. I have removed the 328P and tried the loopback test - it still didn't work (nothing echoed in the serial console)

  2. With an external power supply, I read 5V from the 5V output, but there is barely any voltage from the 3.3V output.

It's a clone by the looks of it; compare it with an image of a real one

But it has the 16U2 (the square chip next to the USB connector); the fact that it's recognised as Uno also indicates that.

My conclusions are that at least the 16U2 is not working properly and that the 3.3V regulator is also gone. I would not be inclined to fix it but if I was , that's what I would start fixing. If the board works after that, it might be unreliable as one can't judge if the 328P is dying a slow death.

Final conclusion: throw it away.

Thanks - replacing the 16U2 is way above my rudimentary soldering skillset so I agree with the "toss it" assessment - I'll bring it to the local electronic waste drop-off when pandemic permits.

FWIW I realized it doesn't have the Arduino name/logo so it's a bona-fide clone.

If the 16U2 is shot, you can cut the traces it has with D0/D1 and use an external USB/Serial adapter (FTDI Basic) for serial downloading.

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