N810 power on issue and the temperature theory
 

I'm not sure if this is old news or not, but it seems to be working...

I recall reading somewhere, I think it was a blog, but it could have been a post here - a theory that the temperature was the cause of the power on issue. At first I thought that was a pretty dumb conclusion and it didn't really seem logical. I'm definitely not one to believe something simply because someone wrote it. I don't think the blog had any evidence to prove the theory so I didn't think much of the post and passed it over fairly quickly.

However, I've recently reflashed my N810 twice, something that has required plenty of restarts. In my effort to try to bypass the annoyance of not being able to get my N810 to turn back on for at least 5 mins after turning it off (every single time), I said what the heck, I'll give the temp thing a try. So when my N810 stopped turning on, I sat it near a poorly insulated window (there were wild winds last night and air was pouring in) for about a minute, picked it up, hit the power button and viola. I was pretty surprised, but just one test wasn't going to prove anything to me.

I repeated the same steps of not being able to get it to turn on, leaving it by the window for a minute or two, then having it turn on the first try after it had the chance to cool way down several times. Again today I took advantage of the very cold weather outside, and after shutting my N810 down due to it locking up, I tried to get it to turn back on which was a no go. I ran outside, set it for one minute or less on a tablet, came back out and turned it on without a problem. It seems like it is becoming apparent that temperature is the deciding factor of whether or not it will turn back on, but why?

Apparently the N810 (and maybe the other tablets) have a temp sensor in them. Maybe the N810 is designed to not be able to turn on if it is too hot, but that threshold was erroneously set too low, or changed by some other factor.

What does everyone thing about this? Has anyone else had success with the temp theory?

Re: N810 power on issue and the temperature theory
 

Just install
* internal-temp
from http://nitapps.com/
and record internal temps every sec before it goes off and it goes on back to see if it counts.

Another problem is electronics, electronic parts and platine.
I don't suggest you to use hair-dryer with cold and hot blow
to see how it can influence electronics inside, as not to let you damage your tablet.

So record temps first looking for any relation.

Darius

N810 (and probably other Nokia tablets) also have an internal temperature sensor. Because tablets generate very little heat when idle, you can use this sensor to measure ambient temperature. internal-temp is a command-line tool to read the sensor.

[user@nokia ~]$ internal-temp
23.25C

Download here.

Re: N810 power on issue and the temperature theory
 

Is there any way for it to start checking temps as soon as it can after it boots?

Re: N810 power on issue and the temperature theory
 

N810's max allowed temperature is 80C

[user@nokia ~]$ cat /sys/devices/platform/i2c_omap.1/i2c-1/1-0048/temp1_crit
80000

I doubt you are exceeding it.

Re: N810 power on issue and the temperature theory
 

Is it possible that somewhere along the line that number is being modified of effected by some other factor? Maybe it is the first thing to be checked before a full power on, and something goes wrong in that process.

Re: N810 power on issue and the temperature theory
 

No. Nokia has already stated that it's a race condition.

Re: N810 power on issue and the temperature theory
 

Race condition?

Re: N810 power on issue and the temperature theory
 

Re: N810 power on issue and the temperature theory
 

I see, is that all we know so far? I didn't know Nokia had even acknowledged the problem. Is there anyway that temp is a factor in that race? It seems so apparent that temperature is effecting its ability to turn on... is it just coincidence?

Re: N810 power on issue and the temperature theory
 

Yes, you should've seen mention of the bugzilla bug several times in several of the power on threads here. :)

Yes, temp can affect race conditions, no, it doesn't have anything to do with the temperature sensor.