Xperia Z wont boot and vibrates 3 times continiously while showing red notification led

[AFill4]

My Xperia Z shut down unexpectedly and hasn't turned back on. When I plug it into the wall charger, the phone vibrates once, the led turns on red, and after a few seconds, the phone vibrates three times. After that, the led turns off and the cycle starts over again. After reading a few threads hinting a problem with the battery, I opened the phone up and removed the battery. When I plug the phone into the wall charger without the battery inserted, the red led turns on, and the screen light up with the sony logo. After a few seconds the phone turns itself off again and the cycle starts over. However, when I plug it into my computer (late 2013 21 inch iMac) the screen doesn't turn on and the led lights up blue. When I try to boot it into fastboot mode, nothing happens and the phone still won't start.

Would anybody have encountered the same problem and have some solutions for it?

[Thommo]

Try performing a system repair using PC Companion as this will often fix issues - 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 on screen 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

[AFill4]

Hi, thank you for your reply.

The problem is that my phone will not start up at all, no matter which mode I try to boot it into, and it is therefore not recognisable by any pc software.

It will always go into the vibration loop I mentionned earlier, except if I remove the battery. If I do that, when connected the phone to the computer, the led will simply light up blue and nothing happens.

[Thommo · Accepted solution]

Then you need to either return your device to the place of purchase or contact Xperia care http://www.sonymobile.com/global-en/support/contact-us/

[AFill4]

Ok thank you