Undefined LED behavior (imp002)

My Imp flashes the status LED in a pattern I don’t see in the list of ledcodes nor the blinkup guide. When I turn on the power, it flashes red and green fast. Then it alternates long red and short green for a while, it is never off. Finally, the LED settles at solid red. The device is connected, and blinkup works. This didn’t happen before I moved the breakout board from the buck converter I got from SmartMaker, to my DC-DC isolated power supply.
Does anybody know what the Imp is trying to indicate?

It sounds like your LED circuit is connected incorrectly.

I don’t think it is, it’s a simple circuit that’s easy to verify. I noticed now that if I cycle the power off for one second, the LED starts flashing normally, and eventually turns off.

It does sound like the imp is maybe browning out and resetting. The fact that this only happened when you moved to your power supply is suspicious too - got a circuit diagram/part numbers/etc?