Xperia Z3 Plus Rebooting

[thewelder]

I have a Xperia z3 Plus E6553 Phone that just starting rebooting out of the blue, I did a factory reset thinking an app was causing it only to find that immediately after the reset it was doing it again. So i'm thinking possibly a battery issue? I just leave it rebooting  then sometimes  it starts then seems to work fine all day , Then randomly it starts rebooting in a loop for hours sometimes , very odd, any ideas how i can test the phone fully.?
TIA
Chris

[Uliwooly]

@thewelder 

This happened to me before and it was a faulty SIM card, could you remove the SIM card and see if you experience the same issue? 

[thewelder]

Hi

I actually took out the sim card and sd card yesterday hoping it would help but sadly no.

Chris

[_alexdon_]

@thewelder @Uliwooly is there a notification when it shuts down? Like battery temperature too high? 

[thewelder]

@_alexdon_ 

No. but this is strange, I used the Sony Companion software, even though it didn't detect the phone I ran the software repair and it restored the phone, which now seems to be working fine now, I don't understand why the factory reset didn't work though. Anyway all is well. 

Chris.

[_alexdon_]

@thewelder good to hear. Keep us updated.