I'm in need of some explanation as my Pi is acting weird (to my limited knowledge at least)

It will only boot when i suply it with 5v/GND through the 3.3/GND GPIOs.

  • The pi boots when i connect 5v to the 3.3v pin (with only the yellow led blinking, nothing on the red, and gives the little thunder icon on its raspbian desktop)

  • It boots normally with the expected behavior on both leds (and no thunder icon) when i connect both the micro usb charger and the second power supply to the 3.3v+GND.

  • Tried two different micro usb power supplies alone, nothing, they only light the red led (no yellow led blinking). Tried 5v+gnd (from a 16x relay board) to the 5v+GND, nothing.

  • The 5v power i am connecting is from this Powered 16x Relay board (stack exchange link)

  • It's a relatively new setup (a month old) and it's been working ok till today that i disconnected the power from the relay module to reboot it.

Have i fried something?
I imagined the micro USB might be damaged, but how would that explain the fact that i need to power it through the 3.3 and not the 5v?
How can i make it boot with just its official power supply again?

  • 1
    Probably. The Foundation says "Under no circumstances should a power source be connected to the 3.3V pins". See Raspberry Pi Power Limitations
    – Milliways
    Commented Apr 21, 2017 at 2:54
  • @Milliways is the module supposed to act as a powersource? is it normal that its pins read out 5v? Check the link i provided on me asking how to connect the 16relay module. It was the only way to get it to work.
    – krasatos
    Commented Apr 21, 2017 at 7:43
  • It is not feasible to check all the hardware and the link does not point to any module. You stated "The pi boots when i connect 5v to the 3.3v pin" and "suply it with 5v/GND through the 3.3/GND". I suggest you disconnect everything to make sure your Pi works, DO NOT connect power to ANYTHING except the USB power port. If you have already asked a question, you should modify the original. I was only responding to this question.
    – Milliways
    Commented Apr 21, 2017 at 8:47
  • Thanks for your reply @Milliways, Check the 3rd bullet on my question: When i connect ONLY usb, i get just red led on and no boot
    – krasatos
    Commented Apr 21, 2017 at 8:51
  • In this case your Pi is probably dead! There are other possibilities, blown polyfuse (try in 24 hours) or SD Card problems.
    – Milliways
    Commented Apr 21, 2017 at 8:54


Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Browse other questions tagged or ask your own question.