How to Fix Fried Arduino Nano/Uno/Mega





Introduction: How to Fix Fried Arduino Nano/Uno/Mega

While I was working on a project which includes an arduino I accidentally shorted it and now its dead. But it can be fixed really easily, So lets get started !

In this post I am fixing the Arduino nano if you have fried Uno or mega skip to step 7, but do read all steps once.

Step 1: Watch the Video

If you get bored of reading stuff you can watch my videos on YouTube ! Click Here

Step 2: Analyzing the Problem !

There are two ways in which you can burn your arduino

1) USB

2) External Vin pin

Step 3: USB

If you were using USB to power your arduino when it died if you flip it around you will see a black component, which is a diode and if u look closely it has a small bulge area or a spot swelled indicating it is dead which is the case for me so replacing it will fix the arduino, but before fixing it lets look at the other way you might have shorted it.

Step 4: Vin Pin

If you were using Vin pin when it died then if you flip it around you will see a small bulge area on this which is a voltage regulator replacing this will fix your issue, but in my case it works via Vin pin but not USB so I need to replace the diode so let's do it

Step 5: Components & Tools!

1) Soldering Iron

2)SMD MBR0520Tp Schottky Diode

3)AMS1117 5V

Step 6: Soldering !

I don't have SMD Schottky Diode at the movement so I will be using general purpose short key diode.

And its time for the Soldering

I have turned the legs of diode for my convenience.

and Its done !

Step 7: For Uno and Mega

Similarly if you have shorted your Arduino Uno or Mega, You need to replace 500mA Fuse(Shown in pic 2) or Voltage regulator(Shown in pic 3) which is same as nano

It will fix the issue !

Step 8: Thank You !

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Questions & Answers


Good to know! =D

Very clear instructable, thanks for sharing the information...

I recently fixed an Arduino Mega because of a blown voltage regulator (a few months ago). Thanks for putting up such a clear Instructable and video for others who may find themselves in the same situation. I hate seeing good stuff thrown away because people don't take the time to figure out what might be wrong.

Great job.

I have 2 Nano's that had blown voltage regulators. I found a package of 15 of them on Ebay for about $4.00 with free shipping. I now have 2 Nano's that are good as new. If you enlarge and look closely at the pic here, you can see the obvious bulge on the regulator. I had to use the finest tip on my soldering station, but with a magnifier it was really a pretty easy fix. Nice Instructable.

happy for you :)

Isn't the fuse on the Uno at least, resettable?

Datasheet gives it as good to 100-A, trip at 1-A typical. Normally, just letting it cool is enough.

In my experience, the diode is the most likely component to burn out. Beware confusing Vin and 5-V out if connecting a supply other than though the 2.1-mm socket

Some Uno's (or other Arduino's, for that matter) have a type of fuse called a PPTC fuse. It is just a resistor, that, when it heats up, increases resistance exponentially. As it cools, the resistance lowers. So, technically, when the PPTC "fuse" trips, there is actually a small current passing through.

It just depends on the manufacturer whether they put that type of fuse on or not.

Yes, you're right. The spec is hold at 500-mA, but as Bourns describe as "trip" at 1000-mA. The point is there is no need to replace unless you whack 100-A through the Uno. It's probably a bit more sophisticated than a PTC resistor, with a defined "knee". A cursory look at the schematic suggests that it only protects the USB supply, by which time you've probably crashed the PC.

Thank you for this post. A quick easy fix for diode replacement on Nano - Thank you.