LED D7 and nothing more


I need help. I got my photon and after first setup everything works fine. Photon is connected to the cloud and log data.
I flash my photon with the following example code:


I ran my photon in this setup:

After running out of battery. My photon is dead. Only LED D7 is on after plugin in USB. Photon is not connected to the cloud and is not responding anymore. I measured voltage between GND and 3v3, it’s 3.7V.

I tryed to bring him in safe mode but without success.

I press RST and SETUP buttons.
released RST and still push SETUP
after few seconds LED flashes Magenta
after few additional seconds LED flashes yellow

Does anyone can help me?

Thank you.

You need to release the SETUP button after it flashes magenta: https://docs.particle.io/guide/getting-started/modes/photon/#safe-mode

There are several threads about this topic and it’s still under investigation for the root cause.
Could you pull an image of your firmware before getting the device running again?

dfu-util -d 2b04:d006 -a 0 -s 0x8000000:0x100000 -U photon_backup.bin

@BDub might like to know about this

Possible threads:

This one is mainly for the Electron but might still be interesting to read

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This would be bad, since it’s max 3.6V on that pin and normally the regulator keeps it at 3.3V.

The fact that your bootloader is still running is encouraging.

If you can put it in blinking yellow (DFU mode) again and run scruff’s command above that would be a helpful first start. Please email me the backup image with a link to this thread.

I will try this… what battery did you use and does it have a protection circuit?

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Thank you for the fast replies!

This is how I measured 3.7 V: https://www.youtube.com/watch?v=g67M2AeC8Q8

And here is how my RGB LED flashes after I hold the buttons: https://www.youtube.com/watch?v=MlYhWRO71Cg

I’m not really sure if I’m bring my photon into DFU mode because the LED flashes in different frequencies compared to https://docs.particle.io/guide/getting-started/modes/photon/#dfu-mode-device-firmware-upgrade-

I running this battery pack (1200 mAh): https://shop.pimoroni.com/products/lipo-battery-pack it has a short circuit protection.

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Hi @BDub,

can you double check if I get my photon in DFU mode by having a short look at this video:


I’m not sure about the frequency of the flashing LED.

thank you very much.

I would recommend plugging the photon into a breadboard instead. That sequence is definitely weird

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thank you @kennethlimcp but this makes no difference. :frowning:

It seems that I can’t get this Photon into DFU mode in order to process @BDub suggestions.

That “color code” looks as if there was some issue with the power supply.
If you’ve got an oszilloscope, could you look at the 3v3 voltage?
Also check for any shorts on pins and make sure the housing of the P0 isn’t somehow dinted (which could short some of the covered components).

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thank you very much for your help.

But I got a new one now :slight_smile:

So what do you guys think? was this situation a stupid one time mistake or shall I take care in general not running out of battery?

That would be a good starting point :wink:

The root cause for that problem is not yet fully found/understood so no cure other than avoiding the circumstances leading up to it.

I fix this problem with the “particle cloud login” and then run the “particle device doctor”.
That command in the terminal try to update the system firmware.