Could it be that 12V is just too much for it to handle? Because I had 2 of the arduinos and both were connected to the 12V, so when I switch to the other one, I could not solve the problem.
I solved this problem before using trail an error (by pluging in the usb and 12V together and removing one of them) but recently, something blew on one of the boards as shown on the photo. I had no idea what it is.
Could it be that the problem is with the LCD display? I am planning to buy an arduino UNO-R3 but not sure if that would fix it.
