Arduino Uno - weird buzzing sound - repair

Yesterday I fried my Arduino Uno, it's still powering on when i plug it in the computer but it wasn't recognizing it. So i took my multimeter and i found that the MSS1P3L diode which is near the DC power supply was broken. So i replaced it and now my computer is able to sends scripts to the arduino, but it still making a weird buzzing sound.

Have you any idea which component might be still broken ? ( I assume that if i'm still able to send data to the arduino, it's not the AMTEL chip).


The only components generally associated with audible noise are capacitors and inductors. A capacitor might make noise if an oscillating signal was fed through it but I would not expect that to happen unless your power supply was not properly filtered. You could press a pencil eraser against each component to see if you can dampen the sound. That should identify the vibrating component.

The regulator is also probably trashed, and maybe the LM358 opamp. Those are usually what dies. The buzzing is likely occurring because one of those failed parts is failing to a near short, and so drawing a lot more current than it normally would (resulting in more ripple current in a cap, causing it to sing - it could also be a cap or inductor in the power supply that you're connecting to it)- you can test the "failed to near-short" theory by touching the suspect parts while it's running - if this is what's happening, the part in question will be hot to the touch. Both parts are cheap to replace.

For the 358, you can carefully cut the pins on one side, or melt solder and lift the pin, then when it's only held by one side you can rest the iron on the other side (adding solder here can help get them all melted at once and get it off pretty easy. With the regulator, you do the same to the pins, and then get the tab last. Flux ("no clean gel flux" is the term to use on amazon/ebay, typically sold in a syringe for easy application) is very helpful for SMD rework, and one tube lasts a very long time.