I bought a Raspberry Pi over a year ago but only just tried to get it working this week but it will not boot. The red light is on and voltage is fine. When I plug in my SD card reader the blue light on the reader lights up so it is being seen by the Raspberry Pi.

Problem Description

Instead of mucking about, I have bought a Raspberry Pi 2. The Pi 2 when powered up has the red light and the green light on full - no blinking but my SD card reader has no blue light. I checked the voltage and I am seeing 5.33 volts.

As an aside, when I first switch the Pi 2 on the blue light on my SD card reader flashes on briefly then goes black.

  • 2
    Rpi boots from the sd card slot in it not from SD card reader. As long as you're getting red light, your power system is alright. Nov 5 '15 at 13:58

Problem Outcome (question now closed)

I bought a RP2 bundle from RS Components but unfortunately they included a standard size SD card so I assumed (wrongly) that I could boot from a SD card reader. I have since purchased a micro SD card and downloaded NOOBS from the Raspberry Pi website. MY RP2 is now working. Thank-you to everyone who responded.


  • Wow. Send RS a note about that, maybe they need to indicate this more clearly to their employees or whoever puts the packages together.
    – goldilocks
    Nov 14 '15 at 19:31

It sounds a little in your question like you might be inserting SD cards with the power on. Don't do that. It won't work and nothing good will happen doing it.

Insert the SD card with the pi unplugged, then power it up. A green light on constantly on a Pi 2 indicates the card was rejected, e.g., because it is not formatted correctly. No green light on an A/B/+ means the same. Or else the hardware is broken, but this seems an unlikely coincidence on both of them.

If you are using a USB SD card adapter (e.g., because you do not have a microSD card), this cannot be used to boot the pi. You have one choice of boot device, the built-in SD card slot. Once an operating system has booted you will be able to use the USB adapter.

  • Thanks anyway but I have formatted a fresh card, downloaded NOOBS and not powered up until everything is connected. The green light is still on full but no boot. My SD card reader blue light 'on' indicator still flashes once but does not stay on permanently.
    – Alistair
    Nov 6 '15 at 11:48
  • You are referring to an external SD card reader (since there is no blue light on the pi). You are wasting your time. As dastaan pointed out 21 hours ago, you must boot from the pi's SD card slot.
    – goldilocks
    Nov 6 '15 at 11:55
  • Okay, got it - thanks. My mistake - didn't read the spec properly!
    – Alistair
    Nov 6 '15 at 14:37
  • If you have a solution to your problem, please tick the big checkmark next to the answer.
    – goldilocks
    Nov 6 '15 at 15:13

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