Restore v20 to 100% Stock (!!even for bricked devices!!)

[Dorasamu]

yep; still on the nougat i downgraded to as well

Thanks, confirmed works.
Downgraded Oreo to Nougat on US996.

Hello, do I need to re-lock the bootloader to be 100% stock? I want to install the Android 8 ota update, my phone is LG V20 H91810U with Android 7

Just did a downgrade from Oreo to Nougat without relocking bootloader.
Still unlocked after flash.

 

[mgzavala]

Thanks, confirmed works.
Downgraded Oreo to Nougat on US996.



Just did a downgrade from Oreo to Nougat without relocking bootloader.
Still unlocked after flash.

How did u do it, did u use a kdz file, cause I get an error: upgrade failed to install when I tried to do it ota. Also I was trying to go back to stock because for some reason I have no cell radio, so I have no phone & data signal, & I was hoping if I went full stock the I can maybe get it to work again

 

[jax0rz]

How did u do it, did u use a kdz file, cause I get an error: upgrade failed to install when I tried to do it ota. Also I was trying to go back to stock because for some reason I have no cell radio, so I have no phone & data signal, & I was hoping if I went full stock the I can maybe get it to work again

honestly, the Oreo update took some of the functionality out of the phone (custom vibrate, auto battery saver at 15%, smart location is buggy, and some other ones i can't remember right now). i'm not sure if your lack of radio signals is software related.. if you are somewhat hands-on you could look into replacing the antennas (there is one at the top and one at the bottom of the phone; the phone is extremely easy to disassemble and a tutorial is easily available on youtube)

 

[CheeseMaster!]

Need some experienced advice on what to do..

I'm having the FRP bypass problem. My stepson factory reset my phone and now I can't set up the new phone. I have all my receipts and verification but I've been overseas so google forgot my phone number when I try to find my account through their recovery process, so after going to Verizon (VS995) they got me in touch with google, and now google says I have to send the phone back to LG to have them flash it. If I can do it my self using a simple step by step process like the instructions posted here.

Will this work?

Thank you

 

[Chyt]

Hi guys,

I need to downgrade my V20 H990DS from oreo to N (sec. upgrade before 2016 dec 31) to get rooted.
Got a kdz for the region from lgfirmwares.blabla.com, downloaded, lgup, dll and stuff installed (well, get the right dll wasn't easy), phone recognized.
But LGUP stucks at 4% (pretty immediately) saying: 0xD AtCmd TxRx Error
I found nowhere anything about this error message. Could you enlighten me please...?
Thanks in advance!

 

[ishb3w]

Alright, so I tried to root my v20 but didn't know I was supposed to remove the google account before wiping, and now im stuck at the frp lock. I tried LGUP downgrading and upgrading and im back on 20c like it was before, but i still can't login. On my google account i removed the phone from my devices, but that didn't help. Should I just send my phone to LG? I bought an S10, so it wouldn't bother me to be without it.

 

[it'sup]

Works's like a charm from Oreo Firmware 91820G back to Nougut 91810P and I might mention not to root or Grind your phones for root fisrt or it probably won't work and you'll be stuck in the same process constantly over and over

 

[noddledizzy]

Will doing this to H918 prevent me from doing this https://forum.xda-developers.com/v20/how-to/step-step-guide-lg-v20-h918-unlocking-t3808258

I'm worried that H918TN will prevent me from doing all that again.

 

[pointbob]

I have lg v20 LS997ZVD sprint flavor. This is zv8 and as such cannot be unlocked by hiddenmenucall.apk

Can someone tell me if i can root it and get it back to zv7? much appreciated..thanks

 

[cnjax]

I have lg v20 LS997ZVD sprint flavor. This is zv8 and as such cannot be unlocked by hiddenmenucall.apk

Can someone tell me if i can root it and get it back to zv7? much appreciated..thanks

You can't downgrade due to sprint incrementing arb, therefore no root

Sent from my LG-H910 using XDA Labs

 

[Vortell]

You can't downgrade due to sprint incrementing arb, therefore no root

There is new root that may work...
https://forum.xda-developers.com/v20/development/3-18-71-perf-root-shell-lg-v20-variants-t3990145

 

[kbhuvi]

I have H990DS currently on 8.0 firmware. I want to downgrade to pre Dec 2016 so as to root the device. LG firmware site does not show any such version for India. Can anyone point to the firmware that would work for me

Regards

 

[asoomal]

Nope, didn't work. Useless phone, not even worth rooting.

 

[N4sha]

Hi guys .
i have lg v20 f800s model and i rooted my phone with f800l rom and then flash vs995 weta rom android 7 version.now that i want flash the official f800s android 9 rom with lgup I get an error invalid KDZ file vs995>>>>f800s please help me.tnx

 

[Landloord]

Hi guys .
i have lg v20 f800s model and i rooted my phone with f800l rom and then flash vs995 weta rom android 7 version.now that i want flash the official f800s android 9 rom with lgup I get an error invalid KDZ file vs995>>>>f800s please help me.tnx

Choose partition dl

 

[Worschtebrot]

How do i know what kdz i have to download.
On the H990 DS Package is a ARE, so i guess its an Arab Emirates Version.
But what kdz do i have to download?

 

[justcosmic]

Hi guys .
i have lg v20 f800s model and i rooted my phone with f800l rom and then flash vs995 weta rom android 7 version.now that i want flash the official f800s android 9 rom with lgup I get an error invalid KDZ file vs995>>>>f800s please help me.tnx

I have the F800S too and can't boot into bootloader. I was wondering about flashing F800L KDZ as I saw that F800L owners seemed to be able to unlock bootloader.
So was thinking of doing this and then have seen successful LOS installs on another thread (unofficial LOS 18 working pretty well!)

Anyway - can you confirm if flashing 800L rom should work ?

Well I just tried - LGUP won't let me install full 800L ROM on my 800S so I tried just in Partition DL - but still won't boot to bootloader...

Would love to know how you managed to get 800L ROM installed on 800S and if that made fastboot available

I've since read that you have to first install F800L official, then use Dirty Santa to unlock bootloader and root - is that correct ?

 

[DaVinniCode]

I have the F800S too and can't boot into bootloader. I was wondering about flashing F800L KDZ as I saw that F800L owners seemed to be able to unlock bootloader.
So was thinking of doing this and then have seen successful LOS installs on another thread (unofficial LOS 18 working pretty well!)

Anyway - can you confirm if flashing 800L rom should work ?

Well I just tried - LGUP won't let me install full 800L ROM on my 800S so I tried just in Partition DL - but still won't boot to bootloader...

Would love to know how you managed to get 800L ROM installed on 800S and if that made fastboot available

I've since read that you have to first install F800L official, then use Dirty Santa to unlock bootloader and root - is that correct ?

I'm dealing with a similar issue. I even installed the full H915 kdz on my H910 which made it functional again, but no fastboot mode now...
Initially i couldn't install the full kdz with LGUP due to the version mismatch, but used 'partition DL' and got it running again, after that it was branded H915, so then i could flash the full kdz using 'refurbish' in LGUP, but yeah, still no fastboot available.

 

[justcosmic]

I'm dealing with a similar issue. I even installed the full H915 kdz on my H910 which made it functional again, but no fastboot mode now...
Initially i couldn't install the full kdz with LGUP due to the version mismatch, but used 'partition DL' and got it running again, after that it was branded H915, so then i could flash the full kdz using 'refurbish' in LGUP, but yeah, still no fastboot available.

I eventually managed - but it was a long series of several process' and I have read that it is different for 910/915. I hacked together parts of various guides - the closest of which was for F800L. Finally managed to succeed with unlock bootloader and root - using highly adapted dirty santa method.
Check threads on dirty santa for your specific device is the best advice I could give. People are managing to do it so it's possible for sure.

 

[Mandown]

Not sure if it has been said but to help anyone else in my situation. First thing is I decided to flash lineageOS 17.1 from alpha omega ROM, Clean install. Well that was my first mistake because LineageOS sucks at telling you about why you cant just do that and need to downgrade to nougat then to 15.1 or 16 cant remember then 17.1 otherwise the fingerprint sensor and camera/light will break on top of certain apps fail to work like youtube. Restored back to A-O and fingerprint works but the apps still break and camera breaks. Then I LGUP and downgrade back to 13a firmware, problem was settings on boot forever crashes so could not setup phone. After re-re-re flashing 13a KDZ with no fix, I for the heck of it flashed 20c and BOOM everything works again! Then I retried the 13a firmware and once again, WORKS!

Hopefully helps some people, seems a big issue moving to lineageOS and not knowing to downgrade to nougat and incrementally upgrading to the later versions.