Reboot loop in Xperia ZL

[John87]

My Xperia ZL was running very good since last 3.5 years. I updated to 5.1.1  a year ago (2016).

Before 2 days on 23 Aug 17, it switched off. When I turned it on, it showed Optimizing app # of 314 (random no.) and again switched off. I did repeated this for 2 times but it switched off every time. I tried to switch it on while charging and it did switch on and completed optimizing app. As soon as I removed it from charging, after a while it switched off again.

Finally I did Factory data reset and erased Everything. On restarting, it did not show any optimizing app, but the sudden switch off issue remained as it was. It got switched off and switched on only while charging. After reading threads in sony support forums about people facing the same issue, I tried to repair the phone using PC Companion. Out of the Luck, it crashed showing some error.

Now my phone doesn't switch on. I took it to Sony Service Center and explained the engineer everything. They told me that they will do software repair with service charges but they feel that this is mother board related issue.

I have already read following Thread and its 14 pages having 140 messages.

Thread: Reboot loop in Xperia ZL after update to Lollipop

/t5/Xperia-Z-ZL-ZR/Reboot-loop-in-Xperia-ZL-after-update-to-Lollipop/td-p/992453

Now, I have following Questions:

1. Is it a software issue?
2. Is it really Motherboard issue? (as I had my Phone started on charging)
3. Is it battery issue? (My phone showed More than 90% battery every time, whether switched off and turned on multiple times while having above issue + It always had 2 day long battery life)
4. Is it lollipop related issue? Then why I can’t downgrade to KitKat? or How can I downgrade to KitKat?

Please reply as I don’t want to spend money if it’s not going to be repaired.

Plus Service Center people offered me to have some new phone against replacement with 80% price of new phone. Is it really a Sony policy or they have some glitches??

Please note that I am Scientist working with human anatomy, and try to identify each and every issue and resolve it to get anything working. This is only for your knowledge regarding - How much I have tried to get my Xperia ZL working again.

Hope for your earliest reply.

John

Ahmedabad, India

[Uliwooly]

@John87

That seems to be a hardware issue, you could repair the phone once more with XC but it does seem to be hardware rather than software related. 

If its indeed the motherboard, in my opinion it is NOT worth it, why? because that's the most expensive part of a phone, it's pretty much the whole phone, to replace. 

[John87]

@uliwooly

Hi...

Thanks for your prompt reply.

May I know, how can u decide whether it is a hardware issue?? Can't completing the whole software repair not work?? I am a huge sony fan, only because of its quality products (even I am not going for iPhone for the same reason).

Sony Center engineer replied after my description only.

Once again, hoping for your early reply.

John

[Uliwooly]

@John87

If XC doesn't solve the problem the chances are that it is hardware related, no one can tell you exactly what it is through a forum, live chat, phonecall, email, etc, until they physically inspect the phone. 

You are free to buy any other brand, but it doesn't mean that you wont encounter the same, similar or a different issue. At the end of the day, if you have to replace the motherboard on any smartphone it will cost you almost the same as buying a new phone, since its the most expensive part of the phone. 

[John87]

thanks uliwooly...

I am going to Service Center on this tuesday...

Wil let you know the result....

[Uliwooly]

@John87

keep us updated