[T-Mobile LG G4] freeradical426:
Hi everyone,

Please forgive any n00b questions.

I got started with rooting / custom ROMs on a Nexus 4, and I didn't realize at the time that this made things really easy and I didn't need to learn very much about how everything worked. Fast forward to last week -- I decided, at long last, that I was tired of using stock MM on my T-Mo G4 / H811. How hard could it be? Probably not much different from playing on my old Nexus 4 right? Lol, maybe not.

So now 72 hours later, my phone is hard bricked and will not enter download mode. and I need some assistance, if anyone would be so kind.

I will try to recount what I did:

To start with, I was using a Mac, so I used Homebrew to install Android platform tools / ADB.

I decided I wanted to try out LineageOS so I went ahead and followed their very clear steps (on LOS wiki) to unlock the bootloader install TWRP. However, TWRP doesn't seem to have an official build for the G4(!) so I had to look up and use one of the betas from this post. Is this where I went off the rails already? [Of course, very stupidly I also failed to make a complete backup of anything before going on ahead. Rookie mistake.]

After unlocking bootloader and flashing my TWRP beta, I was able to boot into TWRP just fine. I followed the normal prescribed steps of doing a Wipe (normal TWRP defaults -- system, cache, etc.?) before flashing the latest LOS nightly (14.1-something) and also the nano-x64 variety of gapps. I rebooted and got stuck with the LOS boot animation. I let this go for 55 minutes, so I am pretty sure it was an actual bootloop, not just the 1st-time-startup and optimization going on.

I rebooted into TWRP and decided to try a different ROM to see if that was the issue. So I wiped again, flashed another ROM (I believe it was a flavor of AOKP 14.1.x), flashed gapps again, and gave it another try. Again got stuck with an endless bootloop (45 minutes).

Since this is my daily driver, I decided to go back to stock. Found this thread, downloaded the MM-debloated zip, pushed to phone, and again Wiped + Flashed. This time, when I hit reboot, my phone was immediately hard-bricked. No startup screen, no nothing. That was quite unexpected. Also, the first time I had ever HARD bricked a device that I was playing with. Yikes!

Since then, I got a hold of a PC, and have been trying to revive the device by flashing an image to the microSD and booting into Download mode, in the form of this thread or this one.

I did get this to work briefly yesterday, or at least I got to Download Mode / Firmware Update screen, and then attempted to run LGUP with the KDZ file. However I ran into an error at about 9%, and couldn't continue -- and then I had to give back my loaner PC for the day. I also noticed that the LG Mobile Support tool was recognizing my phone NOT as an H811 but as something like HX230 or ... whatever it was, it was definitely wrong. Which is worrisome.

Today I'm giving it another try but my phone will not enter Download Mode at all, nor respond in any other way. I'm curious if this is a battery issue? So I am simply charging it for the time being. I also re-formatted the microSD and re-flashed the single .img just to be safe, but still can't get a response out of the phone. On my PC's device manager it is showing up as the common Qualcomm 9008 that a lot of people seem to have seen. No recognition from LG Mobile Support tool, nor from LGUP.

So ... what now?

It's possible that once my battery gets some charge again, maybe I'll be able to enter DL mode. Let's hope so.

However, I am also totally in the dark about which software version I should be using. 20i? 20p? I have no idea what these refer to, and I did not make any prior notes to capture the state that my phone was in before this all began. So IF I get to DL mode I will definitely need further instruction on the CORRECT KDZ FILE to be flashing. Else I will just compound my problems.

ANY tips or suggestions will be appreciated! Thanks so much.