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New RPi seems not to work

Former Member

I have recently got an RPi, downloaded the Raspian OS, put the image on an SD card with WinImager and plugged in.

I use an USB power supply ( 5V 1A) and connected to a TV. I just wanted to see it all boot up before I got a suitable keyboard,

network connection, etc. Much to my disappointment, I saw nothing. I checked the voltage at TP1, and that appears OK ( 4.8V),

the power light is on and some chips appear to get warm.

Can anyone please suggest what to check to determine if I have a dud RPi or if I have done something incorrectly?

 

John

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  • in reply to johnbeetem

    Thank you for these suggestions.

    I went through the list in the troubleshooting guide, and wrote to the card using dd rather than WinImager. But, was not able to get anything out of the RPi.

    I did try a different card ( all were 4GB), but whether either of them was on the list, I am not sure.

    I found it a little difficult to get sufficient ID to be sure. Certainly the file structure seems to be OK, and all the files mentioned in the discussions seem present. Oh and I also tried archlinux.

    John

  • in reply to Former Member

    I have now had some time to look at this.

    I was able to locate a power supply with a current indicator. This made it clear that the board was not functioning.

    On the board, the red power light was on, all other lights off.

    The measured values were as follows -

    Voltage@TP1( +5V) = 4.92V; ( implies that the fuse is not damaged)

    Voltage( +2.5V @C15) = 2.48V;

    Voltage( +1.8V@C9) = 1.8V;

    Current( total in ) = 0.17A. ( This should be at least 0.7A from what I can gather from the discussions.)

    ( Component designators from the schematic, 17Apr2012)

    Clearly, this is most likely the current for the peripheral circuit, and the CPU is not drawing current. No amount of fiddling with the rest is going to help.

    I think this is unambiguous evidence for a faulty board.

    Thank you to everyone who offered help.

  • in reply to Former Member

    This begs the Question....Is there other faulty boards out there?

  • in reply to Former Member

    All good.

     

    It was his SD Card (verbatim 4gb sdhc class 4 - sd k04g - 1009ww5282b).  Can someone please add this to the problem list on the wiki.

     

    Fergus

  • in reply to Former Member

    I was able to locate a power supply with a current indicator. This made it clear that the board was not functioning.

    How so ?

     

    Current( total in ) = 0.17A. ( This should be at least 0.7A from what I can gather from the discussions.)

    No, When booted a model B uses approx 450mA plus whatever your peripherals require. Stress the GPU and you may use more.

     

    Clearly, this is most likely the current for the peripheral circuit, and the CPU is not drawing current. No amount of fiddling with the rest is going to help.

    My fully functional R-Pi with all peripherals connected draws ~75mA when I install a deliberately erased sd card. So I'm not sure what, if anything, it tells you.

    Yes, you may have a faulty Pi, or sd cards that are somehow incompatible, or an issue with writing the image etc. It's hard to tell.

     

    However, unless you can acquire a known working sd card with an image on it that's been proven to work in another Pi I don't know if it's possible to definately say it's faulty - yet.

  • in reply to Former Member

    It appears that I was a little hasty in my conclusion.