[adam_kay]

Hello there.

Due to upgrading to G5 I decideed to sell my G3.
I was running CM13 (one of the latest nightlies), 21C modem and TWRP 2.8.6, so it seemed like a good idea to go back to stock-ish firmware.
To do so, I installed stock ROM using this method with 21A modem.

Everything worked fine. I had a working LG ROM.
Then I had this great idea of mine to install even 'stocker' firmware with LG UP. (I couldn't do that while running CM13 - LG UP didn't recognize the phone)
And that was the moment when everything fell apart.
It took a few minutes for LGUP to 'install' the new firmware. When phone finally rebooted, I got stuck in TWRP. There was no chance to boot a system.
I tried this fix and it didn't help.
I also tried to restore my nandroid backup (i made it on clean CM13) and it didn't work either.

Then, I thought "How hard can it be?" and went crazy: wiping, formatting, trying to flash new modem (this tme 30B hybrid), boot, system and doing probably all the things I shouldn't do.

So the conclusion is: I have a nice gold brick with working TWRP, adb and LG's download mode, but nothing more than that.
No chance to boot to system and I guess with a pretty messed up system partition.
Also, I think there's some problem with flashing anything, as I don't see any lines while installing, just a few seconds and info about succeeded flashing.

Is there anyone who could help me?

Thank you,
Adam

[DTTR]

@adam_kay

Yes, but on a different forum.
Search on Google for "how to revert lg g3 to stock" and you will find a method and a how to tutorial.

You'll get a non-rooted g3.