Boot failure No lights

my rev C was running for weeks plugged in via usb
To an iPhone charger. I had a wifi dongle attached, but
Was using Ethernet for network as I hadn't gotten the wifi working.

The other day I noticed it was off yet still plugged into usb.

I tried connecting it to 5v ax adapter without wifi dongle attached. I get a brief led light
Next to the 5v port that quickly shuts off. No other leds come on ever.

It acts like a dead unit. This was running Debian that shipped with
The rev c. Should I try to get a mini sdmc with Debian image and insert
That in the sdmc slot??

I've tried all variables I can think of including known good ac adapters. Should
I get an rma process going?

Appreciating all responses on this topic,