I'll start by saying that I probably shorted something to cause this.
I noticed this behavior the next morning after spilling some water next to it. I didn't think any got on it through the holes in its case, but I'm thinking I may be wrong about that.
Now the green ACT light blinks 4 times in sequence when plugged in.
Raspberry Pi model B 512mb running headless piCore player
- Removed the SD card that was in it and successfully booted another Pi up with that card.
- Re-imaged another (previously tested) SD card with Win32diskimager with a fresh copy of a previously tested Raspbian image.
- Placed the Pi on 3 other power supplies. All previously tested to work on this and other Pi's.
- Verified that the voltage between TP1 and TP2 is approximately 4.93vdc.
- Tried it with nothing plugged in besides SD card and power.
- Tried the card with Raspbian on it hooked up to HDMI - no signal getting to the display.
- Left it on and blinking for an hour - normal temperature when I checked it.
I don't see any visually obvious discolorations or other failures.
Is there anything else I can check or do with it before tossing it?