Originally Posted by ruggyboss
Actually I think warranty is gone when you root.. So don't worry, it can't be worse than this
Originally Posted by play3maniac
I was only asking, because i was curious about it. Thank you for the answer.
I think, at least here in Portugal, that you lose your warranty, when you unlock the bootloader, speacialy because of the DRM keys. Unrooting the phone is easy, you only have to repair phone software, since i still have my factory ROM. I already did it. Rooted, went back to stock and rooted again, the bootloader was never touched, thanks to the guys who created the Easy Root Tool.
The only way they could be 100% sure that you've rooted your device is sending it in rooted state or with unlocked bootloader.
Ways to retain warranty of the Z1
Root with locked bootloader (that was never unlocked) :
Flash any stock FTF, latest one preferably.
If you want to retain warranty whilst having unlocked bootloader then you'll have to root your device and make a backup of your TA partition. If you want your warranty back:
Flash stock FTF root it - restore TA backup flash latest stock FTF again.
This way you can unlock the bootloader whilst keeping the warranty.
Unlocking the bootloader without doing a TA backup before = warranty lost forever. No other method of relocking it will get you back your warranty.
That's pretty much it.
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