manmetdehamer
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Joined: Sat Dec 22, 2012 8:42 pm

Raspberry Pi not booting wierd voltage reading

Sat Dec 22, 2012 8:46 pm

Today i was playing some video's using my raspberry.
when suddenly it stopped working. I pulled the power and put it back in.
But now its not booting anymore. The red light lights up the green one is faint.

I tried another charger and reformated the sd card, this dint solve it.
I used a multi meter to check t1 > t2 and for some reason its reading 8 volt ><
While the samsung charger im using from my samsung phone im using says 5v 1a max.

Anyone has an idea to what could be causing this, and even better howto solve it?

cnt
Posts: 60
Joined: Wed Sep 26, 2012 4:42 am

Re: Raspberry Pi not booting wierd voltage reading

Sat Dec 22, 2012 9:02 pm

the only thing that could cause that is a bad power supply. I have no idea how tolerant the rpi is to over voltage but that is not a good sign :(

manmetdehamer
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Joined: Sat Dec 22, 2012 8:42 pm

Re: Raspberry Pi not booting wierd voltage reading

Sat Dec 22, 2012 9:05 pm

i have tried 3 of our phone chargers here in our house:
my samsung= reading 7.9v
and 2 htc chargers both reading 7.9v

wth is happening all these chargers say output 5v 1 a

dknute
Posts: 57
Joined: Thu Nov 08, 2012 9:05 pm

Re: Raspberry Pi not booting wierd voltage reading

Sat Dec 22, 2012 9:14 pm

Replace the battery in your meter :)

As for Pi not booting, the faint light of green LED is usually an indication it wants to boot but something is not right with the SD card (or the image on it). Do you have another card to try with?

manmetdehamer
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Joined: Sat Dec 22, 2012 8:42 pm

Re: Raspberry Pi not booting wierd voltage reading

Sat Dec 22, 2012 9:49 pm

i just tried using another sd card and the same thing happens :(

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redhawk
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Re: Raspberry Pi not booting wierd voltage reading

Sat Dec 22, 2012 9:58 pm

It's unlikely you're reading 8volts the PI has a 5.8v(??) transient suppresser to prevent the output voltage getting too high.
If you're using an analogue voltmeter you should change the battery as one of the posters suggested or use a digital voltmeter instead.

Richard S.

manmetdehamer
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Re: Raspberry Pi not booting wierd voltage reading

Sat Dec 22, 2012 10:07 pm

Ok the battery in my voltage meter was indeed dying... it started to leak replaced it and now the voltage reading is 4.88v but still the faint green led :(

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mahjongg
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Re: Raspberry Pi not booting wierd voltage reading

Sat Dec 22, 2012 10:14 pm

dknute wrote:Replace the battery in your meter :)

As for Pi not booting, the faint light of green LED is usually an indication it wants to boot but something is not right with the SD card (or the image on it). Do you have another card to try with?
err. no! the faint light is caused by the built in pullup of the GPIO started as input on reset, when no code has run to initialise it as an output.
Therefore it means absolutely nothing, other than no code has ran yet!

I see that the tip to replace the battery was already given, that was my first thought too. I'm sure your supplies do not all output 8V!

When not doing (being able to do) a clean shutdown, its possible (but not likely) that open buffers on the SD card were written to the flash in the card, and that can corrupt the card contents!

Wipe the card completely clean, so that the cards logic is reset, and install the OS again.

manmetdehamer
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Joined: Sat Dec 22, 2012 8:42 pm

Re: Raspberry Pi not booting wierd voltage reading

Sat Dec 22, 2012 10:51 pm

hmm did a full wipe and reimaged the sdcard.
Still no joy

drgeoff
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Re: Raspberry Pi not booting wierd voltage reading

Sun Dec 23, 2012 12:36 am

redhawk wrote:If you're using an analogue voltmeter you should change the battery as one of the posters suggested or use a digital voltmeter instead.

Richard S.
Except in very rare cases, an analogue meter does not use a battery when measuring voltage or current. The battery is only in circuit on the resistance ranges.

manmetdehamer
Posts: 7
Joined: Sat Dec 22, 2012 8:42 pm

Re: Raspberry Pi not booting wierd voltage reading

Sun Dec 23, 2012 7:35 am

well changing the battery worked for my digital meter. but even with another sdcard or newly formatted one iets still bot booting

manmetdehamer
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Joined: Sat Dec 22, 2012 8:42 pm

Re: Raspberry Pi not booting wierd voltage reading

Sun Dec 23, 2012 9:27 am

I just powered the pi over the gpio pins as a test.
Still the same result. Red light and faint green one.

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