N900 Sporadically Heats Up and Drains Battery Quickly
 

Hello Everyone,
I've noticed this behavior occasionally from my N900. I'm using the stock battery and it's not 1 year old yet. The initial symptoms are the N900 heating up (more than usual) for no reason. It's almost like some runaway process is happening. After about 1-2 hours I'll get the double 'doin' sound alerting a critically low battery. Soon after I get alerted of the battery being too low, the unit simply dies out and shuts off.

Has anyone else experienced this? If so, any root cause?

Re: N900 Sporadically Heats Up and Drains Battery Quickly
 

I have several times had a hildon process hang, drawing 100% CPU. Phone get really warm and runs quickly through the battery.

I can switch between desktops, make phone calls and use running programs.

But I can't start any applications from shortcuts on the desktop, and not interact with any widgets. It is possible to start applications using the menu system. It's just everything on the desktop that is shown but not accessible.

Killing the runaway task - SIGKILL, not SIGTERM - seems to solve the problem.

Re: N900 Sporadically Heats Up and Drains Battery Quickly
 

When phone heats up you can start xterm and look for runaway processes with top command.

Re: N900 Sporadically Heats Up and Drains Battery Quickly
 

When I used to have wifi set to "automatically switch to wlan when available", or something like that, wifi would occasionally start using large amounts of power for no reason. hasn't happened since I turned it off.

Re: N900 Sporadically Heats Up and Drains Battery Quickly
 

Yes, all applications work. I will try to look for run away processes. I will use

$top

as slender suggested.

Re: N900 Sporadically Heats Up and Drains Battery Quickly
 

I will take a look at the wifi also. Thanks!

Re: N900 Sporadically Heats Up and Drains Battery Quickly
 

I have exactly the same problem described by Chiques, had flashed my phone also but this didn't solve the problem. My battery drains out within 4-5 hours without any use. Is this something with the processes running at that time or this is kind of a hardware issue?

Re: N900 Sporadically Heats Up and Drains Battery Quickly
 

This is normal behavior for the N900. Please undervolt, and stay away from 800MHz+.

Re: N900 Sporadically Heats Up and Drains Battery Quickly
 

in winter, I think this is a "feature".

...


sorry, I couldn't help myself.

Re: N900 Sporadically Heats Up and Drains Battery Quickly
 

I didn't get it. I have had this phone for a couple of months now and this behaviour has just starting a couple of days back. I am still in the same area so frequency change doesn't apply here.

Re: N900 Sporadically Heats Up and Drains Battery Quickly
 

He's talking about CPU overclocking. But discard it as a possibility if you didn't overclock it (or if you don't know what it is).
N900 comes with 600mhz as the stock frequency so it shouldn't be a problem.

Re: N900 Sporadically Heats Up and Drains Battery Quickly
 

It's not normal. Mine is stock too and mine last around a day so it's definately some process running in background and draining battery.
Try top in xterminal when it happens again and post the result/screenshot here. As can't say without knowing what process is doing this.

Re: N900 Sporadically Heats Up and Drains Battery Quickly
 

It's not normal, I've never had this happen to me, except where some app I've written has sat at 100% CPU.

It would be interesting to know exactly what is causing your CPU usage mind you.

Re: N900 Sporadically Heats Up and Drains Battery Quickly
 

same problem here. I ran an upgrade using the nokia package manager (don't know which packages were updated), and before finishing all packages I see a reboot happening, and on the white Nokia screen I see a message that it's upgrading something (prob. flashing). Then, after a while the icons on the desktop stopped responding, which happens also some time after rebooting the phone.

Now, I have removed all widgets from my desktop, and the unresponsive icons problem is gone, but the phone still runs through its battery much faster than before, even though no process in 'top' shows large % of CPU use..

I have had no time yet to check which packages got updated. what I did see is that dpkg.log is empty.

Any hints on what to check for in syslog?

Re: N900 Sporadically Heats Up and Drains Battery Quickly
 

Iirc there was a cron script somewhere on the forum (or you could just write one easily enough) which would record the output of ps every now and again. That would give you some indication of what's running when it shouldn't be.

Re: N900 Sporadically Heats Up and Drains Battery Quickly
 

rebooting is the only work around for me

Re: N900 Sporadically Heats Up and Drains Battery Quickly
 

maybe one should have an autokill-runaway-process-deamon like they have in Villainrom for Android... or make the n900 vibrate or bipe if it starts to get too warm

Re: N900 Sporadically Heats Up and Drains Battery Quickly
 

post the result of top here when your cpu usage is high and then we can do something about it. Most likely it will be hildon.

Re: N900 Sporadically Heats Up and Drains Battery Quickly
 

I got the same problem recently, may be about a week, as I see most of the people posting here got this problem last 1-2 months, so obviously it is something with an update of an app and unfortunatelly I do not know what I recently uptated as well. It heats up when when I connect to wifi and start using the internet, after a little the internet dies but it shows that I am still connected to the network, the battery dies shortly after. Only reboot fix is it. When I am not connected to internet the phone is working fine. Any ideas now what I can do...??? Really need to do something cause I bought the phone becuase of Skype and so without internet it is just useless for me...

Re: N900 Sporadically Heats Up and Drains Battery Quickly
 

even i experience the same.. i am running at a clock spped of 800mhz.. and my phone switches off in 4hrs.. is my N900 normal?? i dont experience any heating effect but when i use my gprs it comes for 4hrs.. help me pls..N900 is just a box if it doesnt have a net connection.. pls help..

Re: N900 Sporadically Heats Up and Drains Battery Quickly
 

Had the same symtpoms and an USB mulfunction. Official Nokia Service Center asked me 300 euros to reprair since it require mainboard replacement.

My threads:

http://talk.maemo.org/showthread.php?t=73308

http://talk.maemo.org/showthread.php?t=74127

If i were you, i'd reflash from scratch.

Re: N900 Sporadically Heats Up and Drains Battery Quickly
 

A friend of mine who also has an N900 told me, that his N900 does this too. It might have gotten wet once in his pocket. Its stock, no overclocking, nothing installed, not connected to anywhere, but a full battery dies in just 6-7 hours, even when the phone is turned off.

Re: N900 Sporadically Heats Up and Drains Battery Quickly
 

If you're using custom modified wifi driver, then it's its fault. It is a known problem that if you leave the custom wifi driver on it will suck all your battery out.

Re: N900 Sporadically Heats Up and Drains Battery Quickly
 

No custom wifi driver here at least.

Re: N900 Sporadically Heats Up and Drains Battery Quickly
 

i had the same problem appear yesterday but after i uninstalled the maemo geolocation service from microb it has worked just fine.
however the geolocation addon is persisting to reinstall itself for some odd reason. :/

Re: N900 Sporadically Heats Up and Drains Battery Quickly
 

As I see more and more people are having the same trouble... still no real answer... ok the problem again happens after connection to the internet, I am not a electronic specialist, but if the WiFi was burned or broken by getting wet or something else, it should not be working at all, right?

... and it works, it connects, it starts to transfer data, it heats up as soon as the data transfer starts and shortly after dies (the internet I mean, the conncetion is still on)... then the battery starts to drain...

so.... here we are at the problem!!!

Re: N900 Sporadically Heats Up and Drains Battery Quickly
 

Guys this is a very helpful thread! (Once again I love this site and my N900, even when the "brick" sucks, and it all is so much better than discussions.apple.com)

Here is my newbie question, if one can help: How do I figure out what processes are?

I used the $top x-terminal command, as suggested by someone above, but need a way to look things up. (Plain Googling is not very effective).

Update: for example "/usr/lib/tracker/tr" spikes up randomly interfering with music playback :( How do I figure what it is?
Thanks!