1810-24G stuck in self-test (J9803A)

[mhs093]

 From what I can see, the 1810-24G switch that I have is stuck in self-test mode, or isn't completing the boot sequence. When I plug it in, all of the LEDs (port and power) light as usual, then all of the port LEDs go out but the Power, Fault, and Locator LEDs stay lit, and the switch doesn't pass any network traffic. I've tried the factory reset instructions, however it always ends with the same symptom as described above. It never gets any further.

I've tried to warranty it, but HP support is not cooperating and is refusing to honor the lifetime warranty becuase I cannot find the invoice from several years ago. Is there anything else I can try before I toss it?