XZ1 repeatly restarting

[Meandthem]

My Xperia XZ1 has occasionally apparently restarted on its own but today it has happened more times than I can count  What is the problem? 

[Qatrium]

@Meandthem

Might be a 3rd party app acting up. Start troubleshooting by restarting your phone into safe mode, this will disable all installed 3rd party apps. If the problem is resolved then one of your installed apps is causing this issue and you have to figure out which one. Start by uninstalling those apps you installed recently.

If this doesn't help, perform a software repair using Xperia Companion. This will do a clean installation of the latest firmware and will also wipe your internal memory. Don't forget to backup using Xperia Companion, but preferably without adding apps or settings to the backup.

Follow the steps given in blue links, and keep us updated.

[wpeterw123]

My XZ1 does exactly the same as your phone and I have had lots of discussions about it with my supplier. I have sent it back about 5 times and each time it came back with the same problem. Now they say they won't take it back again so I sent it to Sony to finally get to the bottom of this and guess what, it still has the same fault. All of what you have told is not worth the time or effort doing as when my phone came back from Sony I hadn't even loaded my sim card ,memory card or any third party apps and it still does it. Everytime I get phone back everyone just says no fault found which is obviously rubbish. I personally do not think they check phones rigorously enough or the problem would be found and it would be too expensive for them to replace faulty phones. Anyway my conclusion is nothing WILL be done by Sony so we either have to just suffer it or chuck an expensive handset in the bin and vote by our feet and NOT buy another Sony phone EVER. So if Sony looks at these posts they will get the message.