[Galaxy S III I9305 (4G LTE + 2GB RAM) Android Deve] flashviking:
10 Steps on How to Make the i9305 Work Great!

I have had troubles with random reboots throughout the fall running on weekly official. Following the experienced issues and the thread I came to the conclusion that the problem was in the modem as other users have pointed out as well.

These are the exact steps on how I got it to work perfectly (so far). Combining two guides posted by [MENTION=6171753]rgib[/MENTION] in thread description and post by [MENTION=5608736]PURJUJU[/MENTION], this is how I made it work:

0 _

# Backup

- Always backup whatever you think you need or think you might need. I did not have much, so I only backed up some apps using oandbackups from F-Droid.

1 _

_ download odin for windows

# odin

http://xdaforums.com/showthread.php?t=2711451

2 _

_ flash the latest stock rom with odin (ap button)

# I9305XXUFQG1

http://updato.com/firmware-archive-select-model?record=65E064847BE811E7963AFA163EE8F90B

- I tested running this Stock ROM with my i9305 bought in a Nordic country and it did not work at all with system apps crashing all the time. Thus I crossed my fingers that LOS14.1 would work with patched modem.

3 _

_ flashed twrp recovery with odin (ap button)

# twrp

https://xdaforums.com/showpost.php?p=74720527&postcount=572

- I downloaded the unofficial version of latest TWRP recovery 3.2.1.0 found through the forum link above.

4 _

#Wipe data

Wiped all data (system, data, cache - ART/Dalvik) in TWRP

- It does not work installing any ROM over another different without wipe.

Stock > LOS official/unofficial = does not work

LOS official weekly > LOS unofficial daily = Tried dirty flashing and can confirm it doesn't work

LOS official > LOS official = Works well because that's dirty flashing. :)

5 _

# Modem

Flashed latest modem (tar.md5-file):https://www.dropbox.com/s/eior9qfri8njcza/I9305XXUFQG1_modem_flashable.zip?dl=0

6 _

_ flashed LineageOS in TWRP recovery

# LineageOS unofficial daily build by [MENTION=382340]walter79[/MENTION]

http://buildyourownandroid.selfhost.eu/smartphone/daily-builds/

- I installed unofficial daily build for now in order to ensure latest build and fixes and try to avoid as many bugs as possible. Will definitely re-do the proceduce and install weekly official build when the device is added back on to the official build roster.

7 _

# OpenGApps (optional)

http://opengapps.org/

- I then flashed opengapps ARM v.7.1.2. minimal package for Google Play functionality.

8 _

# SU

- Flashed SU TWRP extras for SuperUser Root: https://download.lineageos.org/extras - without it I could only root over ADB according to Developer Options.

9 _

#Reboot

Then reboot into system.

10 _

#Done

- System running without any crashes for at least 24 hours. No more modem crashes during telephone calls nor while moving between cell towers which used to cause system reboots and required entering SIM PIN-code.

# Conclusion

Looking forward to another great year with LineageOS!

Thanks for great contributions everyone engaged in this!

Happy flashing!

//FlashVIking

---------- Post added at 04:06 PM ---------- Previous post was at 04:03 PM ----------

Tried a dirty flash from official to unofficial and can confirm it did not work.