[Xperia Z Q&A, Help & Troubleshooting] HyperEscape:
Hello All,

Tried searching for a case peculiar as mine, wasnt able to find one so here is the lowdown.

1. Xperia C6603 , originally had 4.2.2 stock ROM which was working fine with my local network. Dont remember the baseband version.

2. Used XperiFirm to download the latest firmware as reported in the list. Dont know what does the suffix RxD (R1D--R8D) means. Anyone please explain. As per the below screenshot downloaded version "C6603_Customized HK_1270-5695_10.5.1.A.0.292_R1D" .

3. Before flashing the downloaded firmware I flashed the dualrecovery from XZDualRecovery. I made a TWRP backup of the 4.2.2 stock ROM on an external SD card, for all partitions including TA,system,boot etc.

4. Used Flashtool to convert the downloaded (step 2) firmware "FILES" format to a flashable FTF file. Flashed the firmware , which went on smoothly.

5. At the first startup I got the following screen , telling me that it is a prototype device/firmware . I went on to see that the network which was working fine with stock ROM 4.2.2 was no longer available.

I tried to go to settings to check and search for networks, which shows available networks, but unable to get itself registered to the SIM providers network. Tried all the settings combinations in menu "*#*#4636*#*#" , nothing makes it work to get the GSM network connectivity back. It is supposedly on the correct setting of LTE/WCDMA/GSM which my current operator supports. Following is the "About" screen for current baseband version.

Tried going in the "Service" menu via "*#*#7378423#*#*" , with the following info, having an unknown modem configuration.

6. Tried reverting back to the old TWRP backup, for which I needed the TWRP recovery loaded on the phone. So ran the XZDualRecovery script again (with the new 4.4 ROM on the phone), however the script hangs around in the end and never reboots the phone with the TWRP recovery. So i am unable to revert and use the stock ROM backups .

7. I dont want to root/unlock the bootloader, however I tried installing TWRP via its "XZrecovery.apk", but it requires busybox (which requires a rooted phone). So i tried the rooting script from [GUIDE] How to root 10.5.1.A.0.283 / 10.5.1.A.0.292 [Locked Bootloader], but it also hangs around in the end and never delivers a rooted phone.

8. Tried looking around for assortment of xperia Z baseband files to check and see if flashing it separately can make it work, however to no avail the the condition persists.

Either ways having a prototype version on the phone which transmits all data back to sony is not desirable at all. So need to replace it for sure. Currently I am stuck in the middle without a clue of how to go back and restore the 4.2.2 TWRP backup, or to actually flash a "non-prototype" or retail version of 4.4.x .

Any help/guidance/suggestions to remedy would be appreciated.

Thanks.

=====================UPDATE

Ok followed the instructions at [GUIDE] How to root 10.5.1.A.0.283 / 10.5.1.A.0.292 [Locked Bootloader] , read carefully again to flash the .230 kernel. Flashed the XZDualRecovery and got the TWRP recovery back.

Restored the old 4.2.2 TWRP backup , hoping that everything would go back to normal. However with a successul restore and a reboot, I was amazed to see I still have no network connectivity. The baseband version is "9x15A-ACEFWMAZQ-30110068-44" . Another noticeable thing was that after the restore and first boot, I still got the "prototype device" message again, which was not there when I first booted the device with original stock 4.2.2 ROM before this flashing adventure began.

Any ideas what may have gone bad.

Thanks.

=======================================

Just got to know that my device is a BROWN device, its IMEI number starts from 0044 so it is a prototype. Any ideas is it really good or bad to have one. Also I see that after another restore of the original stock 4.2.2 ROM it is barely getting the signals indoor (1 bar only). The signal reception is very weak and sporadic . Should i keep the device or not and is there any remedy or network signal strength.

Thanks.