Xperia S giving problem after ICS update

[harpreet936]

I purchased Xperia S a month back with default ROM GB, unfortunately i clicked ICS update and my phone got updated to ICS. But after update ICS have too many bugs like delay in opeining Dialer, wifi problem and the main Proximity sensor missed to get active in 2 calls out of 50 calls. This problem occurs twice in 50 calls. I had been following up with Sony service centre, according to that degrade to GB is now discontinued and cannot be happen, as these problems were not there in GB.

Please help me to resolve the issue to how revert the original GB rom

[Thommo]

Yes if your bootloader is locked

If it's unlocked and you want to relock then using Flashtool as you will to downgrade run the .FTF file from the link below

Xperia-S Relock Bootloader.ftf

https://docs.google.com/open?id=0B-yM_qnM8ZPRTDhsS1ZHbXJ2YWs

[harpreet936]

so it means that locking bootloader again may not void warranty and through SUS the phone can be updated.

[Thommo · Accepted solution]

If you have unlocked your bootloader then you may void your warranty according to Sony's site

When your bootloader is unlocked PCC and SUS will detect modified software and fail to update.

Re-Locking your bootloader will allow PCC and SUS to updateyour phone

[harpreet936]

what about DRM keys, after debranding and locked the bootloader.

[Thommo]

My bootloader is unlocked and I'm rooted and the only issue I found was that TrackID stopped working so because I'm rooted I uninstalled TrackID then went to the Play store and re-installed it and now it works fine - However will this effect the warranty? I'm going to say no because of a recent case invloving Sony and unlocked bootloaders - See case below

http://www.xperiablog.net/2012/08/03/sony-clarifies-warranty-guidance-if-you-unlock-your-bootloader/

So I hope this helps - Locking the bootloader will allow you to use PCC and SUS to update via official channels

[harpreet936]

Dear Thommo

Thanks a lot!

I did the debranding, was sucessful. And the great news that the, bootloader is locked, root status - not rooted and Track ID is working (default one)

Now I am happy, with GB 2.3.7, and will now not go for ICS update, this update has so many bugs

[ronykaks]

hey harpreet !!. i too want too downgrade my new xperia s to gb from ics,,!!.. without tampering my warranty!!!

i read all ur all ur earlier post but didnt get much of it ....bootloader , debranding and  DRM, this all is very confusing for me...this is my first smartphone and u can consider me as a layman in this field.

as of now i have only installed pc companion and media go on my pc for backup and synczation.  

can u guide me step by step  for downgrading.to gb 2.3.7?

and will i b able to upgrade to ics easily when required.?

will all data b lost while downgrading?

how do u check the rooting status and bootloader thing? wat should their status b?

kindly help!!

[harpreet936]

first step is a tutorial given here

http://www.xperiablog.net/2012/03/26/debrand-your-xperia-s-tutorial/

All steps are given in the tutorial are very easy to understand and for the ROM download you can serach my post also (ROM given by Thommo)

Main step to be consider is locating and installing all drivers first by PCC or SUS from sonymobile web site

I think you should go through the above link thoroughly and understand the same and if get confused then i will help you for the same.

[ronykaks]

hey thankz harpreet now i have an idea how to do it but still i have few queries.

1.In the tutorial theres a line

Also tick ‘Unknown sources’ under Menu –> Settings –> Applications

where to find this uknown sources opt on my xperia s ver ics?

2.did u used the indian generic rom given by thommo ? ne issues in that after installation?

3.after degrading will i b able to upgarde it when required !!.and wat abt the warranty of phone after degrading?

[ronykaks]

one more thing in my phone unlocking bootloader allowed is yes ..does that mean that i ll have to unlock the bootloader first before performing the downgrade?