Upload doesen't work: Arduino Mega 2560

Hello everyone,

I have a problem with my Arduino Mega 2560. Uploading of any code doesn't work. I tried the easiest one "Blink" and also a lot of other examples. When I try to upload the code first the L light blink twice. Then the TX RX lights blink once or twice and then the L light is on constantly.

I tried all the stuff from the list in the troubleshooting guide (only the cable I wasn't able to change because I don't have another one at the moment)

By the way: I bought the board a half year ago and it worked well. I toke it with me on a flight to the USA one month ago. So it was in my baggage. After that I tried to use it yesterday and it didn't work.It didn't look like it has any demage.

So I think maybe the cold temperatuer in the airplain's baggage area could have destroyed anything. --> Any Idea what could have been happened?

Or did anyone else have had the same problem and can may help me? Even if you can post me an old forum entry you would help me a lot.

Thank you very much.


What didn’t work? Did the IDE (arduino software) give an error? (What was it? Copy and paste.) Did the board just not function correctly? In what way?

It sounds like your cable and arduino work. Did you make sure you have the correct board and serial port selected?

Did you upload any custom code the last time you had it working correctly? I'm seeing almost exactly what you described on my Mega 2650 but in my case the error is caused by a sketch I uploaded tying up the serial connection and preventing anything else from being uploaded.

PS. If anyone out there knows of a way the clear out a bad sketch please let me know.


When I tried I take the original code from the IDE Examples. Nothing customized.

The IDE doesn't give any error. You see how it compile the code if I press on the upload button. Then it shows "uploading to board" and nothing happens. Thats also the time when the RX TX lights went off and the L light get on for all the time.

I choose the correct board and the correct COM port. I rechecked it in the hardware manageer and even change the port there. But nothing work at all. I deactivated my firewall for a while, it also not work.

@bucpatr: I thought of anything like that to--> kind of old code. But I cant find a way to get it away. The 1-10 seconds wait with reset I tried to.

Maybe something has been damaged at the flight or when they have X-rayed it.

What could I do if the board get any kind of radio chock and some parts of the bootloader storage has been deleted? --> or anything simiular.

If anyone has any other idea or soltion how to solve the problem I would be very happy!