Arduino Uno - TX/RX lights dont blink upon plugging USB - Cant upload software

Hello all,

I have a relatively new problem on my hands. I cannot write software to my arduino uno, despite having power from USB and not having anything in RX pin 0.

The arduino pops up in my device manager under COM3 everytime I plug it in, however, when I first plug it in, or try to upload software, the TX/RX pins never blink, and I always get an avrdude "out of sync" error.

Any help would be much appreciated.

Got anything in Tx pin 1?

Anything different happen with your Uno recently?

Does Tools:Board and Tools:Serial Port show the right things?

The only thing different as of recent was running the Arduino Uno from a 12V project lithium ion battery.
The arduino was warm to the touch after using this type of battery for about 5 minutes... starting to get scared that something fried perhaps.

The board type and correct com port show in the tools setting.

To update, it appears the crystal clock shroud was quite hot to the touch.

Nothing is connected to either TX or RX

Sounds like something fried then. Nothing should be hot on the board except the 5V regulator if running from 12V and using lots of current.