Xperia Z wierd shut down problem~

[Kelvin12]

I got a serious wired problem with my xperia z.

It started last week, with the simcard disconnect and I have to reconnected a couple times.

Then, today it just just down without any apparent reasons. When it's off i try to turn it on again, and it come to the sony logo a couple sec later it shut down. Sometimes it does make it on to the homescreen and shuts down after like 5-10 sconds.. Some times it doesn't make it to the homescreen and just shuts down.

Also, I notice the back is very hot. Is it a battery problem?

Any solutions? I have been using this phone fine for like since I bought it and these things just happen suddenly..

Please help.

This phone is using everything stock. 

Android~ 4.3 (as the update hasn't been release in my country yet)
Buil number 10.4.1.B.101

[_alexdon_]

Did you try to use the phone in safe mode?

http://talk.sonymobile.com/t5/FAQ/How-to-boot-your-phone-into-safe-mode/m-p/348008

[Kelvin12]

Yes, even when I reboot to safe mode, the phone can't even boot up..  It automatically shuts down after the "xperia" word came out when booting.. Some times it make it to the home page but then it shuts down after a couple of seconds.. basically..

Please help. =( Anybody!!

[Kelvin12]

This is the battery picture from my phone after the sudden weird shutdown problem.... As u can see, there is a weird hiatus of out no where.. and after rebooting, the battery percentage is reduced tremendously.. like 20-30%

And also, after I restart my phone from the weird shutdown.. The wifi connection password which I was connected to was removed..  Don't know if this info helps at all... but.... this is all the symptoms of my phone..

[_alexdon_]

Download SUS and repair:

http://www.sonymobile.com/gb/tools/update-service/

[Dimgalad_PT]

It looks similar to my problem... Any advice? Still have got no luck with normal restores and stuff...

[_alexdon_]

Stop by a sony service if a repair with SUS does not help.

[Kelvin12]

I found the cause of the problem.. Just by turning off the stamina mode, the phone is back and kicking. Just without the stamina mode. Probably you can try to force stop and relauch the stamina mode process. I could be bothered anyway. My phone's battery is more than sufficient. take care.. good luck to all having similiar problems

[Dimgalad_PT]

Thing is... i DONT have the stamina mode turned on... This is the thread very similar to my problem, @alexdon

[_alexdon_]

I see that.You can reset stamina like this: first disable it,after go to settings-apps-all-eco mode controller,force stop and clear data.Restart your device and enable stamina.