PI 2 undervoltage warning

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132110
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PI 2 undervoltage warning

Post by 132110 » Wed Feb 24, 2016 11:17 am

Hi,

on my Raspi 2, red led is always off. I have meassured voltage before fuse and it's a bit more then 5V, and after fuse it's 4.50 with nothing connected but microsd. Also, i did try another power supply and few other cables - red led is still off.

I bought Rasbarry Pi 2, Power Supply 5.25V/2A and SanDisk 8GB NOOBS micro SD but was unaware of led meanings till yesterday.

Rpi does work, but there are problem from time to time with networking or i just have to reboot it.

Order ID: 132110
Date Ordered: 29/01/2016

Any advice?

Best regards

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Jake
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Re: PI 2 undervoltage warning

Post by Jake » Thu Feb 25, 2016 5:46 pm

Hi,

I would suggest the undervolt warning is caused by the power supply (not the Raspberry Pi). Have you tried it with an alternative power supply and cable that can definitely supply 2A?

-- Jake
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BMS Doug
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Re: PI 2 undervoltage warning

Post by BMS Doug » Fri Feb 26, 2016 9:52 am

Do you see a small rainbow square in the top right corner of the screen when using the Pi? (This is the low voltage indicator).

I'm inclined to think that your Power LED is broken, if you can use the Pi at all it should be on.

The drop from Just over 5V to about 4.5V is to be expected, the polyfuse in normal operation will have a volt drop of about half a volt.
http://elinux.org/Polyfuses_explained
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132110
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Re: PI 2 undervoltage warning

Post by 132110 » Fri Feb 26, 2016 2:57 pm

Power supply i bought is this :
http://www.modmypi.com/raspberry-pi/acc ... d-cable-eu

I did try changing power supply with that from my LG G3 - it's 5V - 2A. Also, I changed cables...

Result is always the same, red power led is off, and there is rainbow square in upper right corner of my screen. :(

Can it be something wrong with the fuse ? What else can be done ?

BMS Doug
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Re: PI 2 undervoltage warning

Post by BMS Doug » Fri Feb 26, 2016 4:50 pm

Are you using a WIFI dongle or wired ethernet?
(older WIFI dongles are very power hungry)

Do you have a powered USB Hub available to test the Pi with no USB devices connected?

Is anything else connected to the Pi?
Doug.

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132110
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Re: PI 2 undervoltage warning

Post by 132110 » Sat Feb 27, 2016 8:44 pm

Hi,

undervoltage warning is happening with nothing connected but monitor(i can see rainbow square). Same thing is happening where monitor is not conneted(i can see that red led is off). Undervoltage warning is happening with wired network connected too. No USB devices are conneted.

Any clues?


Regards

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Dave
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Re: PI 2 undervoltage warning

Post by Dave » Tue Mar 01, 2016 10:05 am

If you have tried multiple power supplies, and had nothing plugged into the Pi other than a monitor and you still get the power rainbow, then I'd be inclined to say its a faulty Pi. All through that does seem a bit odd.

I'll get sales to contact you and arrange a return.
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132110
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Re: PI 2 undervoltage warning

Post by 132110 » Tue Mar 01, 2016 11:46 am

There is one more thing i didn't try to change and that is microsd card. I'll try that later today and report back...

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