Not sure what happened. I’ve read a bunch of other threads that they were able to bring them back to life (grounding D4-7, forcing it back into DFU mode). No luck so far.
Several of them mention some way of fixing this with a JTAG, but I don’t have the board for that.
Anyone know of any other things to try?
What happened prior to this dim blue led symptom?
Do you have another Photon?
Wish I knew. I didn’t boot it for a couple weeks while waiting for some parts. I was surprised to not see it boot when hooking everything back up. Unfortunately, it’s the only one I have.
What happens if you hold on the MODE/SETUP button before powering on?
Same thing. Just the single dim D7 LED.
Not sure if @rickkas7 can help and see it this can be replaced?
You should create a support ticket at https://particle.io/support and include a link to this post.