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Posts: 10 | Thanked: 0 times | Joined on Oct 2010
#1
Hi, yesterday I've disconnected my fully-charged n900 from my PC (I heard strange noise in pc speakers when connected).

Then wake up in morning and battery was dead! (below "safe" level - had to charge it up with desktop battery charger).

Now my investigation stopped at the point when I've found that turned off n900 eats ~230mA is that possible ?

Could anyone check battery current when his n900 is turned off, please? I've used standard multimeter and crocodiles.
 
Posts: 10 | Thanked: 0 times | Joined on Oct 2010
#2
I've found that battery runs warm (40 Celcius) even when phone is switched off.. that's definitively a short-circuit somewhere.

My guess was USB port but seems USB works ok (connects to pc, charging). Any ideas before I'll go to nearest nokia care ?
 
Posts: 1,680 | Thanked: 3,685 times | Joined on Jan 2011
#3
Put the multimeter away son...

Obviously you have installed somthing that is causing massive amounts of wake ups and stopping the phone going into standby. You have two choices.

1. a. Figure out how to use Powertop, top, ps, kill, apt-get remove.
b. Diagnose fault and rectify.

2. Backup your contacts and just reflash that mthfckr. Watch what you install next time around.


If you search for 'powertop' in powersearch you will find lots of threads of people attempting to 'hand hold' people through diagnosing the fault...it NEVER turns out well. (unless your name is switch_, but he had some prior linux knowledge.)
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N900: One of God's own prototypes. A high-powered mutant of some kind never even considered for mass production. Too weird to live, and too rare to die.
 
icebox's Avatar
Posts: 282 | Thanked: 120 times | Joined on Nov 2007
#4
If by off you mean TURNED OFF (not stand by) than the above advice is useless.

Maybe the battery it self could be the cause.

OTOH, humor me, how do you measure your power usage (between what points, etc?
 
Posts: 10 | Thanked: 0 times | Joined on Oct 2010
#5
Originally Posted by vi_ View Post
Put the multimeter away son...

Obviously you have installed somthing that is causing massive amounts of wake ups and stopping the phone going into standby. You have two choices.

1. a. Figure out how to use Powertop, top, ps, kill, apt-get remove.
b. Diagnose fault and rectify.

2. Backup your contacts and just reflash that mthfckr. Watch what you install next time around.

Forrgot to mention.. I've reflashed that b**ch at the very first step (full reflash = kernel, rootfs etc). Still same thing..
 
Posts: 10 | Thanked: 0 times | Joined on Oct 2010
#6
Originally Posted by icebox View Post
Maybe the battery it self could be the cause.
Battery is ok, works perfectly on my alt-phone (nokia c6) more even battery from that phone also deploys after 4hrs of use in n900. Both are BL-5J batts

Originally Posted by icebox View Post
OTOH, humor me, how do you measure your power usage (between what points, etc?
Pinned in between battery and device. I've used 3 crocodiles, some wires and made a man-in-the-middle checks on every of 3 lines. (+) was 250mA, (-) obviously -250mA, and 3rd lines gaves 0 - it's some kind of data line or battery check or sth, nvm.

Thx for giving a shot. Other thoughts someone ?

Tomorrow I'm sending it to nokiacare.

Last edited by gravisrs; 2011-05-17 at 17:31.
 
Posts: 1,680 | Thanked: 3,685 times | Joined on Jan 2011
#7
So you were measuring a discharge of half an amp? Wtf, why wasn't it on fire?
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N900: One of God's own prototypes. A high-powered mutant of some kind never even considered for mass production. Too weird to live, and too rare to die.
 
Posts: 10 | Thanked: 0 times | Joined on Oct 2010
#8
Quarter Amp actually, but yes, it boils my eggs in my pocket
 
ndi's Avatar
Posts: 2,050 | Thanked: 1,425 times | Joined on Dec 2009 @ Bucharest
#9
A watt. Had that happen to me too, left in pocket with recaller stuck. Munched the battery from decent to near-dead in an hour. It was not on fire because the battery (and phone) can deal with 0.5C without any issues, I have discharged the battery in 2 hours several times. That's 600 mA at 4V, two and a half watts.

Kind of explains the weight, doesn't it. It must have a cool heat sink in there

Seriously though, I was worried, battery sensor said 48. Or 52. Don't remember, I was quite busy powering down and blowing on the device with keyboard open and back cover removed. Still works.

Oh, overclocking helps.
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N900 dead and Nokia no longer replaces them. Thanks for all the fish.

Keep the forums clean: use "Thanks" button instead of the thank you post.
 
Posts: 10 | Thanked: 0 times | Joined on Oct 2010
#10
Ok got another thought. Tested my friend's n900 with multimeter and found the "bug". His n900 takes 230mA just for 1 second after powering up (phone turned off, we're talking about connecting the battery to turned off phone). Mine stays in that "stage" forever. Seems like some low-level boot sequence (POST?) fails and powers something that shouldn't be powered all the time.

I'll post a reason from nokia care (if they give me some info what was wrong).
 
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