Photon getting hot and flashing SOS +1, can't flash tinker or update



I fear I may have cooked my photon. From what I gather from the docs i seem to have encountered a hard fault ( SOS +1 red light flashing), and the photon gets much hotter than I have ever noticed. So hot that it hurts to press the reset or setup buttons.

If i act fast (before it gets too hot to handle) i can get it to dfu mode, but any attempt to update or flash tinker via usb kicks back errors. For example, this is part of the error i get when trying to flash tinker;

dfu-util: Invalid DFU suffix signature
dfu-util: A valid DFU suffix will be required in a future dfu-util release!!!
Deducing device DFU version from functional descriptor length
Opening DFU capable USB device...
ID 2b04:d006
Run-time device DFU version 011a
Claiming USB DFU Interface...
Setting Alternate Setting #0 ...
Determining device status: state = dfuIDLE, status = 0
dfuIDLE, continuing
DFU mode device DFU version 011a
Device returned transfer size 4096
DfuSe interface name: "Internal Flash   "
Downloading to address = 0x080a0000, size = 3952
Download	[                         ]   0%            0 bytesdfu-util: Error during download get_status

Error writing firmware...dfu-util: 
Invalid DFU suffix signature
dfu-util: A valid DFU suffix will be required in a future dfu-util release!!!

dfu-util: Error during download get_status

I have search the forum and the docs to no avail. Any insight is greatly appreciated.


I don’t have photon. What kind of power did you add on Photon? USB, Batteries, Voltage, etc.

Can you show us wiring board.


Currently I have it only to usb and not wired up to anything, i believe that the usb supplies 5v but could be wrong. I do also have a power shield and the device reacts the same when hooked up to that.

I dont have a full circuit diagram at the ready but i can tell you that i have 7 of the circuit found in the link below as well as some simple circuits for sensors, dsb1820, a few float valves, etc.

Here is the like referenced above

I have tried almost everything i could find on the forum to no avail.



I am also unable to get the device into safe mode. As soon as it starts blinking magenta and I release the setup button it is back to the red sos+1 flashing. I can’t let the stay on for longer than a minute otherwise its too hot to handle.

Should I lose all hope and order a new one, with the hopes that i dont fry that one too?


What DFU did you type?


@jjlee32, the onboard 3.3v switching regulator is most likely damaged which is what is getting hot. This can happen with too-long or poor quality USB cables or a poor quality power supply or a combo of both. If you have a multimeter, measure the voltage on the 3V3 pin.

You can replace the regulator or power the Photon from an external 3V3 supply via the 3V3 pin.


That’s sort of where I am hung up. It says a suffix is required so I do not know what to type in.


I have tried with the stock cord and other micro USB cords i have laying around to no avail.

Would the onboard regulator be affected when the power shield is used because even when I put in on the shield it does the same sos+1


Once the regulator is damaged - which is most likely the case with your description above - changing supply or wires won’t fix that anymore. The damage has been done and the regulator needs replacing.


Is this something I can do on my own? it doesn’t look like it, based off the resistors being the type that a precise robot arm would put into place. It seems that the regulator could be buried inside the layers of the photon. Do i even attempt to locate and replace the regulator?

I have ordered a new one already, but is there anything i could have done to prevent this form happening? I have had that photon for over a year and it has taken all of the noobish abuse one of those can take but was pretty reliable until now. Could it have been a code issue is my main concern?

Thank you all for your help thus far


With a steady hand (or three ;-)), good eyesight and a good soldering iron you can replace the regulator - I’ve done it a couple of times.

Usually you won’t be able to damage the regulator by code alone.


Thanks for all of your help thus far. Is it the regulator directly above the setup button?

I dont think ill take that project on but it’d be nice to know if i ever decide to try and repair this one.


So I was without my DMM for a few days, but now i have it back.

The voltage across the 3v3 pin is still 3.3 V and the Vin pin reads ~5V when connected via usb.

Could there be another hardware fault that could be causing this issue? I want to make sure i do not make the same mistake again.