Temp sensor, battery or motherboard problem?

[alvincheng]

I bought a Xperia S on March last year and used more than a year.

I have a battery monitor app in it, and know the temperature of my smartphone.

In last month, the temperature result is abnormal. Sometimes it is 65c, sometimes, -15 or 100.

But I don't feel it too cold or too hot, and I don't play games and videos.

Whatever the abnormal results, the phone automatically shut down but not reboot after a while.

When I turn it on again, it will shut down again and again, and will be normal for a certain period of time.

I did factory reset and nothing helps, but I found that it happens when I put my phone in my pocket with a passport with a plastic protection cover (see here), or putting a phone in a crowded area.

If I put it in a pocket where there are no other things, this does not happen.

So, I determine that it is due to the hardware problem.

But I would like to confirm if it is the temperature sensor, battery or motherboard problem.

Or, it is the normal reaction that I do not use it or place it appropriately.

Hope someone can answer. Thanks a lot!

[alvincheng]

I have a screenshot which can show what happened one day.

[Rickard]

Don't know if it could cause this problem but some cases has a magnet in them. Make sure you don't have any magnet near the phone when this happens.

If that's not the problem there must be some type of hardware problem in your phone but it's impossible to say what the problem is without further investigation of the phone. I suggest you contact a service location or your local Sony Xperia support (http://www.sonymobile.com/global-en/support/contact-us/).