Thanks for your idea. Unfortunately, no upload is possible. I get "Programmer is not responding" errors.
This didn't surprise me, as there is no LED lit on the board. My recollection is that there is a power LED that should be on.
In any event, there's power, and the USB chip is responding, but I'm not able to get the attention of the Arduino CPU.
Is there anything else I can measure or try before we replace the board?
Thanks,
Dick