Phone keeps shutting off suddenly. Runs without an issue in safemode.

[newfett22]

I am beyond frusterated. My phone (Xperia T) keeps suddenly shutting off whenever I try to do anything. When I power it back on it generally shuts itself down again. It will run for about 6 hours max without doing this.. but only if I hardly use it. I can't figure out why. I used PC Companion and made sure that everything was up-to-date. I am running it in safemode at the moment, which so far has prevented it from turning itself off. My phone seemed to have developed this issue among others such as apps crashing, mainly Messages.. after the last System Update. It's as if it can't handle it.  

Things I've tried:

- Factory reset : this did nothing.

- PC Companion software update : this also did nothing.

- Shut down and power up in safemode: this seems to help. It hasn't hut itself down as of yet.

- Removing it from it's phone case : I did this because the phone usually seems a little too warm whenever it shuts down. I thought maybe it was an overheating issue.. but running it caseless did nothing helpful.

Possible issues:

- Phone is overheating? Or thinks that it's overheating?

- It's having issues running the newest update? Like it's overwhelming the phone and causing it to crash?

- It's a battery issue? I'll admit that I'm hard on the phone.. it rarely gets powered off (charges everynight while turned on). 

Any input is helpful! And if anyone knows how to downgrade to an OLDER version of Android (this is what I was hoping would happen when I did the Factory reset) let me know!! 

[Thommo · Accepted solution]

Have you tried performing a system repair as this will often fix issues, This is not the same as an update or factory reset - This will factory reset your phone

Switch off your phone and unplug from Pc (Hold volume up and power for around 10 seconds)
Start PC Companion and select Support zone then Update my phone/tablet then in Blue Repair my phone/tablet and follow the onscreen instructions - When prompted connect your phone still switched off holding volume down or back button - This should start the repair or reformat process

If you are using Windows 8/8.1 or a 64bit operating system then adjust the settings for PC Companion and run in compatibility mode and chose Windows 7 or XP

[newfett22]

I'll give that a try. It said I need 80% battery, so I have to let my phone charge a bit more. I'll let you know if it works! Thanks for the help. 

[newfett22]

Seems to have worked! Phone is running better than it has in 6 months! I redownloaded some of my important apps that I'd lost during this whole process, I had about 4 downloading at one time - this heated up my phone.. but it never shut itself off! Couldn't be happier! I'll post an update if anything changes.