Only 3 green/yellow flashes then nothing

My core had been working fine. I have only used the tinker app and not loaded my own code. Changed location and so did a long press on the MODE button to reset to to factory so I could easily change wifi settings.

I didn’t get the slow blue flash during the long press, and also didn’t get the fast blue flash after 10 seconds. Flashing seemed to stop.

Now i get nothing. Pressing the reset button only see a light green (maybe its same as the yellow flash). But it only flashes 3 times, then nothing. I will work through the ‘only yellow flashing’ to see if that helps.

I tried the following

Try holding down both buttons on the core, and release the reset button. Keep holding the other button as it flashes yellow, and keep holding it until the core starts fast flashing white, then release the mode button. When your core resets, it should be slow blinking blue and in listening mode

but I never see the flashing white, posted another video.

My guess is that your RGB LED is showing the R and G, but not the B. Your factory reset rapid “white” flashing happens, except it’s yellow (R+G), and after reboot the Core is probably in listening mode trying to flash blue, but it’s not actually turning the LED on.

Try to confirm this for us—go ahead and try SmartConfig or USB Wi-Fi credentials and see if you get flashing green and then breathing green instead of cyan.

Since you say it used to work fine, if you hold down the RGB LED, the blue LED might get a better connection and come on.

Try those things and post your results here—obviously if your Core is defective, we’ll replace it. Get in touch with me at with any concerns.

Ahh, yes your right. Probing the LEDs blue terminal with my oscilloscope i see it pulsing… let me play around with it some more.

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So playing some more, definitely something terminal with the core… I can connect over USB, and enter credentials, these appear to be accepted correctly. I can read the core id.

As mentioned, probing with my scope I see the blue terminal of the LED pulse immediately after reset (so it is seemingly the blue LED blown, not a dry joint).

Core is only able to get as far as flashing green, does not connect to cloud and cannot get to cyan flashing. I know the credentials and internet I’m using are fine as I can follow the exact procedure and my other core connects perfectly.

Makes me think I somehow fried it… For kicks I may check the SPI, to see if it appears the CC3000 is damaged too…