user71689: I have an Arduino Uno and Mega, but when I connect them to a computer with the USB they came with, there is no green light near the reset button that illuminates.
On the Uno board the pin 13 continuously flashes with red light while on the Mega board the R17 and R18 both illuminate red light but no flashing.
How do I know if the boards work or are damaged?

user85940: Did you try to connect to the computer and upload a blank sketch or a blink sketch...
If the program complies and uploads successfully it is alive.
But you will have to check IO, ADC and other features separately.

71689: <p>I have an Arduino Uno and Mega, but when I connect them to a computer with the USB they came with, there is no green light near the reset button that illuminates.</p>
<p>On the Uno board the pin 13 continuously flashes with red light while on the Mega board the R17 and R18 both illuminate red light but no flashing.</p>
<p>How do I know if the boards work or are damaged?</p>
 85940: <p>Did you try to connect to the computer and upload a blank sketch or a blink sketch...
If the program complies and uploads successfully it is alive.
But you will have to check IO, ADC and other features separately.</p>
