How to recover photon with only dim blue LED on D7 [Solved]


I have looked through the other threads from last year and have tried all the suggested approaches to get into dfu-util mode but none works. I believe that the 2 photons I have which are in this state were loaded with system firmware 0.6.2. They have been operating normally when removed from their circuit board to be upgraded. Any hacks to get these 2 talking.

Disaster – 2 Photons damaged
Photon is not connecting to the cloud - breathing green after cyan breathing for 2 second

Just to clarify, you have tried this already (since that’s what is usually referenced when dim blue LED comes up)?

AFAIK, this does not require you to put the device into DFU Mode.

Electron Solid dim blue D7 LED - Unresponsive
Do I have corrupted bootloader?

Nope - had not seen/found this thread. This removes the need for a JTAG programmer by using another photon. So the issue is a corrupted bootloader. I will try this now. Thanks @ScruffR


I have seen instances where this “Norwegian Blue” approach didn’t help, but using a JTAG programmer did. So it might not always work but it’s definetly worth a try.


Worked like a dream on both of them - no longer 2 dead parrots!


Never seen this before.

I wonder how many of the Photons with dimly lit D7 LED’s that I threw away could have been repaired with this method.


I think this is a ‘feature’ that has fixed in the later than 0.6.2 system firmware. At least, these 2 photons plus 1 with keys issues were all from a batch of this era that I was going back to the field to update to 0.7.0.



I can tell you that this “feature” is still a part of the deviceOS as of 1.4.0 as I have one of these that I will need to now physically retrieve.

Thanks, Chip


You have a dead parrot - a Norwegian Blue?



Yes, an Electron LTE running deviceOS@1.4.0. It got into a low battery state and is now unresponsive and shows the dim blue D7 led.



So clearly the brownout condition can still cause the issue - time to break out the instructions above to revive said dead parrot.


Yes, problem is that the parrot is about 200 miles as the crow (parrot?) flies so it is a bit of a pain.