avrdude stk500_getsync() not in sync resp=0x00

Using Arduino IDE 1.x
1

Hello, im having problem with Arduino uno when uploading a sketch.
I get avrdude stk500_getsync() not in sync resp=0x00

Nothing in connected to the arduino, i've tried everything. The correct drivers and port are selected, tried pressing reset before uploading, rebooting the machine. I swapped the ATMega328 from another arduino uno and same error. (The ATMega from the broken arduino works in the second arduino). So it's not the bootloader.

I've been using the broken arduino in a RC Car and im using 18v to power an Hbridge and the ground used in the Hbridge is the arduino's.
RX and TX leds don't blink when trying to upload.
Could that fried the board? If it's not the ATMega, what could be fried? Anyway to check it?

Thanks!

2

I think your UART IC might burnout. When you connected just check any IC get heating up.