yashsingh1/xdaforums huggingface dataset:
[LG V40 Guides, News, & Discussion] copota:
I seem to have lost fastboot, that is, if I ever had it.

My phone is a LG V40 Sprint variant, that originally had Oreo 8.1 with the ability to OEM unlock. I followed this guide, and successfully flashed V405QA711e_00_NAO_US_OP_0118.kdz, which is a US Cellular Pie firmware that I'm currently on.

I used Refurbish to flash the firmware. The phone is unlocked in developer options with USB debugging enabled.

Now, when I run an ADB command to reboot the bootloader, the phone simply reboots, and does not enter fastboot mode.

I can enter download mode by pressing volume up then plugging in. If I try the fastboot key press method, nothing happens.

Anyone know what I did wrong, and if fastboot is capable on my phones variant? I would like to install TWRP to try Lineage OS, and apparently fastboot is necessary to flash TWRP.

Thanks for any info.
[LG V40 Guides, News, & Discussion] Ainz_Ooal_Gown:
We never had access to Fastboot officially and the OEM unlock in the settings was just a big middle finger to us as users since they are never going to support our variant for and Official Unlock. But question why US cellular Kdz and not US unlocked KDZ? And the only way to have fastboot access for our variant, is to already be rooted with the bootloader unlocked, which i clearly state shouldn't be used with refurbished or upgrade.
[LG V40 Guides, News, & Discussion] copota:
Well, I was just following this guide, as quoted...

"Step 4. Enter download mode and flash any KDZ that is compatible with your device with the Refurbish or Upgrade options."

I used the following KDZ: V405QA720a_03_NAO_US_OP_0529.kdz

I might of stated the name wrong, I believe that is the US unlocked KDZ, and not US Cellular. Someone correct me if I'm wrong. I got the KDZ from a link in this thread... https://xdaforums.com/lg-v40/development/unlocked-kdz-v40511d00-t3881290/page2

Anyhow, I'm back to a Sprint Oreo 8.1 firmware from an KDZ I got in this forum somewhere, I can't find the post. It was from an official LG Link, but it only has a January 2019 security patch, and wont OTA update to the latest security patch. So I guess I'm stuck with Oreo 8.1 with a January patch.

Question: Can TWRP/Lineage be installed on a Sprint variant?

If not, is there a Pie KDZ I can flash that will give me Sprint support and the latest security patch?

Thanks for any help.
[LG V40 Guides, News, & Discussion] Ainz_Ooal_Gown:
Please share the link for Sprint Oreo....that we know of Sprint and AT&T haven't released any KDZ....
[LG V40 Guides, News, & Discussion] Crisvendetta:
Hello.

I have my LG v40 ATT unlocked same as you but I live in europe and cannot get ota updates so I am still on android 8.1.

Will this work for updating from 8.1 to 9 and can my phone get accidentally locked from that? Thanks in advance.
[LG V40 Guides, News, & Discussion] crubbish:
Stuck in Fastboot

Hi. My V40 is 405EBW (Indian) version. I've been trying to flash 20c (Pie) FW over 10c. Having had unlocked BL+Root, I've followed the 'With root' section of the guide. All steps seemed to work and LGUP has shown 100% upon finishing. I've made sure I use Partition DL option. However after that the phone is stuck in Fastboot mode (PRODUCT_NAME - LM-V350EAW). It won't go into download mode showing the message "Your device has failed a routine security check and will not boot".

I've tried to repeat the whole process but to no avail. Can you please point me to the way to rectify this.
[LG V40 Guides, News, & Discussion] Ainz_Ooal_Gown:
Did you make sure to download the correct Pie firmware and 8.0 fastboot/abl won't let you boot Pie....
[LG V40 Guides, News, & Discussion] crubbish:
Yes, been upgrading from Open EU Oreo to Open EU Pie.

Tried to flash TWRP thinking I'd be able to boot to it. It seemed to flash but still can't get anywhere from fastboot.
[LG V40 Guides, News, & Discussion] Ainz_Ooal_Gown:
Then make sure you have the correct abl/fastboot installed
[LG V40 Guides, News, & Discussion] Slystuff:
It's been a while since I last manually flashed changes through to a phone. So if someone could just answer a couple of questions that I have before I attempt it I'd really grateful.

Currently I have the 405EBW which shows software version of V20a-IND-XX, and it's not rooted.

Would flashing across to the GBR equivalent make sense? So far the only region based difference that I know of is that on the Indian software version the camera shutter sound can't be disabled, and the most recent security update is from July.

Following the non root method to flash this, would this wipe any data that I have on the phone? Again it's been a long time since I last flashed anything to a phone (HTC desire / Galaxy S3)

Thanks.
[LG V40 Guides, News, & Discussion] Talysdaddy:
"Would flashing across to the GBR equivalent make sense?"

Well let's see, you mentioned the difference you know of is that the cameras shutter sounds can be disabled. Does it make sense to flash just for this feature? Obviously, this means a great deal to, the ability to take photos discretely without any sounds that may alert others of your actions at the time. Is this something of great importance to me, this one incognito feature? Of course not, I wouldn't think twice of it or felt the need for others input on the subject, but you did so is it really necessary for the input of others on this??

Following the non root method to flash this, would this wipe any data that I have on the phone?

I haven't done this so I can't accurately answer that but can offer a viable alternative, which I've never had a situation where I've wished I hadn't made a backup, but there's plenty times where I didn't have one and wished I did. I can tell you one thing for sure, if it's too much of a hassle to create one, well I know for sure that it's much faster making one and feel nice and fuzzy inside than to have to wait 4+ days for someone to reply with an answer.

BTW, it's not necessary to give a reason for asking questions here, not a requirement here or anything. But since you really wanted readers to know this, stating it twice, in opening and closing. Just as a reminder even for such veterans as yourself, most questions you have likely have been already answered here in some way or another. There's a nice little "search" button near the top of the page where Im sure you'd find many answers you'll have much faster than waiting for someone else's.

Good luck
[LG V40 Guides, News, & Discussion] Slystuff:
From the point of view of input from others on this particular change, those are the differences that I'm aware of, but was looking to see if there were any others that someone might be aware of as I hadn't personally found any via the search on site, that might make it more worthwhile overall, or may even prove to be a detriment (depending on the individual differences)

As for the camera shutter sound difference, it's more of a personal annoyance due to the fact of how load it actually is than anything, but then again that could also be just from being used to always having had it turned off on previous phones.

Thanks for the response, I'll do a bit more digging in the mean time before making up my mind.
[LG V40 Guides, News, & Discussion] xXCoolGuYXx:
So my question is can the lg V40 t mobile be rooted yet
[LG V40 Guides, News, & Discussion] Ainz_Ooal_Gown:
Not that we know of?
[LG V40 Guides, News, & Discussion] xXCoolGuYXx:
Thanks bro hope the root for the LGV40 on T-Mobile comes soon.
[LG V40 Guides, News, & Discussion] LuckyGold40:
Confirmed to crossflash an unlocked ATT LM-405UA to US Unlocked QA ROM using T-Mobile SIM. WiFi calling works. No nearby cell towers that operate Band 71. I'l have to drive into town to test. Stock phone otherwise. I did have to install LG USB Drivers for LGUP to work.
[LG V40 Guides, News, & Discussion] vulcan4d:
I have a refurb LG v40 that won't install Netflix, I'm thinking it was crossflashed with god knows what. It appears to be a Sprint unlocked phone LMV405UA3. Can I use LGUP to flash it back to stock and still keep it unlocked?
[LG V40 Guides, News, & Discussion] Slystuff:
LGUP

Decided to try and cross flash over to the UK Firmware from the Indian one that came with my phone (EBW model).

I've followed the guide in OP's post however for some reason LGUP refuses to open on my PC, has anyone else encountered this at all?
[LG V40 Guides, News, & Discussion] antintin:
Disable anti virus and if it does open but displays some error message just click on x or click past it, and lgup should open
[LG V40 Guides, News, & Discussion] Slystuff:
Thank you, that did trick!

Managed to load LGUP and find my phone, though now I get "Error: 0x6004, CrossDL OPEN_ESA_DS>OPEN_EU_DS"

Is there a known work around for this?
[LG V40 Guides, News, & Discussion] ohhuzoor:
You can flash using lgup 1.15 cmd but let me warn you flashing firmware other than india would result in loss of volte and loose all data stored in phone so make a backup of your data
[LG V40 Guides, News, & Discussion] Icedscottieg:
No change in firmware

Hello all i recently bought a lg lm-v405ua unlocked phone and I'm trying to flash lm-v405qa us unlocked variant.I tried the recommended lg 1.15 cmd with powershell on win 10 everything proceeded fine phone reset but when i checked firmware version it was exactly the same I've even downloaded multiple verison whether oreo or pie im stuck.Thanks for any reply.
[LG V40 Guides, News, & Discussion] whitedavidp:
LGUP Not Starting on Win10

I have a brand new LM-V405QA7USA that has Pie installed at the factory and am considering doing some mods and want to be sure I have a good chance of getting back to stock in case I screw up. I have followed the instructions in this thread and installed all on my Win10 machine. When I try to execute LGUP I get prompted for permission by windows but nothing happens after I grant it. I have the phone in download mode as described in this thread <https://droidrecovery.com/lg-v40-thinq-recovery-mode/>. But I am getting nowhere fast. Any suggestions? Thanks
[LG V40 Guides, News, & Discussion] Slystuff:
You might be having the same issue I had in that it's being blocked from running by your anti-virus program.

Worth checking that and adding it as an exception if it is.
[LG V40 Guides, News, & Discussion] whitedavidp:
The behavior I was seeing made it look like my attempts to flash were failing silently. Turns out they were not failing but not having an impact. I got a clue from some other post on XDA. It turns out that this device has 2 "slots" (A and B) and where only one is active at a time. As system updates roll out, they are put into the non-active slot and then that slot is activated. I was following the guide exactly and it said to flash the V35 bootloader into slot A. It turns out that my slot B was the active one. So after flashing into slot B I was able to move ahead. I believe you can see the currently active slot while in fastboot as a property.
[LG V40 Guides, News, & Discussion] phoneissue:
error: 0x6004, crossDL SPR_US>OPEN_US

solved
[LG V40 Guides, News, & Discussion] raptor k:
this hasn't worked on my device

hello,

my lg v40 has been stuck with a black screen and a question mark in the centre, i cannot enter boot mode so i can't fix it.

can anyone help?
[LG V40 Guides, News, & Discussion] NGOwner:
If you can get back into download mode, load a kgz.

That might work.

[NG]Owner
[LG V40 Guides, News, & Discussion] smokinu:
Hi. I just picked up an LG V40 after using Moto's for the last few phones. No stranger to XDA, but am still a newbie with LG specific procedures.

I've setup LGUP as described in the OP. Trying to do a DUMP to backup the contents of the entire drive first before crossflashing (from Sprint to US Unlocked). Encountered a Locked error message within LGUP. Dumb question....does the phone need to have the bootloader unlocked as a prerequisite to using LGUP???
[LG V40 Guides, News, & Discussion] Ainz_Ooal_Gown:
Are you on Oreo or pie?
[LG V40 Guides, News, & Discussion] whitedavidp:
I personally had no luck with the LGUP pointed at in this thread. From my own personal notes:

Based upon information and dual-mode LGUP download from here

<https://xdaforums.com/showpost.php?p=76995781&postcount=26> and

comments from elsewhere:

1. Run the installer provided: LGUP_Store_Frame_Ver_1_14_3.msi and let it do

its thing.

2 Make sure you are using LGUP in user mode. The SetUser.bat script failed for

me due to permission issues. Even drag/drop file copies did not work. I have

to use copy and paste from the context menus. Essentially, you want to do

this:

copy "%RUNPATH%LGUP_CommonU.dll" "%ProgramFiles(x86)%\LG Electronics\LGUP\model\common\LGUP_Common.dll"

which places the LGUP_CommonU.dll into the proper location with the name

LGUP_Common.dll. Then you want to do this:

copy "%RUNPATH%LGUPU.exe" "%ProgramFiles(x86)%\LG Electronics\LGUP\LGUP.exe"

which places the LGUPU.exe into the proper location with the name LGUP.exe

3. Connect a normally running V40 via USB and start LGUP from the programs

list in Windows. It will show some initializing steps and likely an error

"Can't open new file" which you just ignore. You should see the device in the

upper section on a COM port showing standby.

Obviously, all this depends on having the right drivers installed.
[LG V40 Guides, News, & Discussion] rjcarter3:
Hi. I'm currently running unlocked BL, rooted PIE US cellular 20a. It's noticed a few bugs with Bluetooth and the proximity sensor which I've been putting up with but was thinking about cross flashing to US Unlocked 20e. I have the following questions:

-last time I flashed, I think I downloaded and flashed a Magisk pre-patched boot image. Is there an easy way to patch this 20e image in the KDZ I've downloaded?

-if not, is it necessary that I install TWRP and patch Magisk from there? I guess I'd probably prefer to keep an LG bootloader since I like to run encrypted, but I can forego that if necessary.

-following the guide for root after you skip back to the non-root section I'm still supposed to select refurbish or upgrade options, correct? (does it matter which option I select?)

-if I just wanted to return to US unlocked stock so that I could get OTA updates, I would just keep all the abl and laf options checked and that would flash everything stock and lock the BL again?

-if I ever want to unlock the BL in the future again, I no longer need the Octoplus right? I can do it myself?

Thanks!
[LG V40 Guides, News, & Discussion] NGOwner:
I'll take a stab at these

Not that I know of. We can now via TWRP install Magisk directly.

Yes, install TWRP and Magisk. What does an unlocked bootloader have to do with encryption? Once you're done, I presume you can reencrypt. You just lose access to your data partion via TWRP. I've got a question out myself about that before I go and re-encrypt.

Yes. Select Refurbish. I've found it works better.

Yes, with the exception of bootloader lock. That doesn't occur via KDZ flashing. The bootloader stays unlocked, I and [MENTION=4770959]whitedavidp[/MENTION] have confirmed this.

I presume (I haven't done this, I'm just guessing) that if you want to lock the bootloader, you have to do that via fastboot with the V35 Engineering (or the V35 Engineering + ablpiestock.img) bootloader. Then flash back to the stock bootloader.

Correct. We can use 9008 mode and fastboot to do that.

[NG]Owner
[LG V40 Guides, News, & Discussion] rjcarter3:
Thanks for all the feedback.

So, sequencing things if I want to update my phone to this later version of Pie with root, I should follow this guide with the root option, then Markus's guide for flashing TWRP here and then Xasi's guide for flashing Magisk here. Does that should right to you?
[LG V40 Guides, News, & Discussion] rjcarter3:
So, I went and flashed US unlocked 20E last night. The directions started going sideways at step 5, setting active to slot b. I first got the android logo with the red ! as I recall but lost all fastboot control. Eventually, it booted back up into PIE.

I tried again to set it back to slot b, I got stuck and could only get into download mode. After applying all the LGUP patches, it recognized my phone, and I figured I'd play it safe and do a full factory flash, which was successful. The good news is that the bluetooth bugs I've been seeing with US Cellular 20A have disappeared, but I'm starting to wish I had root again.

I started following Markus's TWRP flashing instructions, but when I run an "adb reboot bootloader" command, it just boots back into PIE. His instructions for forcing recovery by rebooting + usb connection + holding vol up or down don't seem to work for me. If I force a bootloader boot (power and vol down, press and release power at the LG logo screen), I get to what I think is the plain stock bootloader (wipe phone - yes or no, reboot) but I still have no longer fastboot controls from the command prompt. Is it possible that the US unlocked version bootloader is more limited than the US Cellular version?

To answer one of your questions about encryption, the SD card and device encryption were separate but only the SD card was reversible. If you encrypted your phone, the only way to turn it off is with a wipe. For example, I was running fully encrypted, and I decrypted my SD card no problem before I started everything last night figuring that I might be flashing TWRP and Magisk from it at some point along the process.

Interestingly, it seems that the encryption in US Unlocked 20E is also more limited than US Cellular's 20A version. It doesn't appear that you can encrypt the phone itself but just permit it to set a Pin/password before boot. On the US Cellular 20A version, there was a whole process of encrypting the phone once you turned it on. It also doesn't appear that you can totally decrypt your SD Card once you encrypt it on 20E. You are just able to turn off encryption for new files I think? I'm still playing around with it.
[LG V40 Guides, News, & Discussion] whitedavidp:
When you say "If I force a bootloader boot (power and vol down, press and release power at the LG logo screen), I get to what I think is the plain stock bootloader (wipe phone - yes or no, reboot)" I think you are booting into recovery (TWRP) and not bootloader. However you see the stock UI. You must accept a couple times and you will end up in TWRP.
[LG V40 Guides, News, & Discussion] rjcarter3:
I guess I'm just a little confused reading these directions from Markus's guide. Note: I'm bone stock except unlocked bootloader. I don't have TWRP installed yet.

Installation guide:

Copy the twrp image to your phones storage and/or micro sdcard

Start cmd/powershell/terminal with working adb/fastboot

Reboot to bootloader

adb reboot bootloader OR

turn off the phone (or reboot), as soon as it turns on, hold volume down while USB cable is connected

If youre unofficially bootloader unlocked, and you nuked laf, its volume up and USB for you

fastboot boot TWRP-judypn-boot.img

I get to step 3 and it just boots back into PIE no matter what whether I use the adb command or try a manual reboot using usb cable & vol+/-. Makes no difference.

Separately, if I unplug USB and turn off the phone. Then, power on with vol -, release and press pwr on splash screen, I get the "Factory data reset

No (Exit)

Yes"

I think this is the stock recovery? But, I still can't reconnect usb and have access to adb/fastboot. Maybe I should take this back to that thread since I'm kind of getting off track, but just in case you had any ideas...
[LG V40 Guides, News, & Discussion] whitedavidp:
I think you should go to the other thread since this is pretty off topic now. But after I did this, fastboot became power UP and plug in USB.
[LG V40 Guides, News, & Discussion] NGOwner:
This is how you get into TWRP Recovery! This phone doesn't boot directly into TWRP. Select Yes twice, and the phone will boot into TWRP.

[NG]Owner
[LG V40 Guides, News, & Discussion] rjcarter3:
Thanks. A lots gone on in the past 24h.

I somehow nearly bricked my phone in 9008 trying to flash v35eng to abl_a in order to get to fastboot and couldn't get out of 9008. After a tip from Xsavi, I started flashing all the possible corrupt a partitions from b and somehow was able to get into downloader mode on b and restored with LGUP.

My next attempt was more successful. I was able to get into fastboot and booted to twrp. However, when trying to flash twrp to recovery ramdisk, I got an error that I've already forgotten but a forum post for it had Markus saying that twrp was basically tested with I think 20d or earlier? My base flash was 20e.

I had tried to flash to an earlier KDZ but LGUP wouldn't let me. Maybe there's a workaround, but I'm getting kind of tired of working on this. The bugs I was hitting in 20a were mostly gone in 20e and didn't feel like going back. The biggest thing I needed root for at this point was mobile payments, but since I couldn't do that I just relocked the bootloader and called it a day.
[LG V40 Guides, News, & Discussion] vulcan4d:
So LGUP will allow me to upgrade my unlocked 20a to 20e right? If I go through the process does it factory reset the device or can I upgrade on top?
[LG V40 Guides, News, & Discussion] whitedavidp:
Not quite sure what model you have. I have a 405QA7 (unlocked USA) and it updated itself from a to e shortly after I first powered it on. When it did this, it did not reset my device.
[LG V40 Guides, News, & Discussion] NGOwner:
What I've heard is:

Refurbish puts the phone into fresh out of the box condition.

Upgrade in LGUP leaves the data partition intact. If this is indeed the case, I don't know which slot it would flash to, the one in use or the other one. There seem to be a lot of unknowns here.

Flash and find out. Report back. That's how we increase our knowledge base. And as soon as LG releases the KDZ for Android 10 for its device, we'll all be in the same boat.

So go ahead, I'll hold your beer .... :D

[NG]Owner
[LG V40 Guides, News, & Discussion] alexeagle8:
hello I am inexperienced if someone can help me revive my v40 via teamviewer I pay him because a friend tried to change his firmwere and when loading 100% it turned off and no longer turned on it is from the T-mobile company now as the post says I have only one brick LOL
[LG V40 Guides, News, & Discussion] Ainz_Ooal_Gown:
wait so you have a originally T-Mobile V40 and tried to KDZ a different rom?
[LG V40 Guides, News, & Discussion] alexeagle8:
yes my friend i try to install a free room to remove the t-mobile using lgup but when charging 100% it just shuts down and no longer turns on now only recognizes the pc port as qualcoom 9008 but the lgup flash program no longer
[LG V40 Guides, News, & Discussion] whitedavidp:
I am not sure how/if you can recover from that one. Perhaps a repair show, LG, or T-Mobile can help?
[LG V40 Guides, News, & Discussion] Ainz_Ooal_Gown:
Well i did mention in the OP that if you have a T-Mobile device to only flash T-Mobile KDZ or else you would get a brick....but if you have access to 9008 there might be hope...
[LG V40 Guides, News, & Discussion] serpent android:
hi all.can you pleasr guide as to what variant of v40 is the best..i mean att,verizon,t mobile,and korean
[LG V40 Guides, News, & Discussion] Ainz_Ooal_Gown:
Well if your in the US technically the best is the US unlocked V40...
[LG V40 Guides, News, & Discussion] mrvoidman:
[MENTION=5104057]Ainz_Ooal_Gown[/MENTION], Thanks for posting this. I’ve read a lot but I’m having difficulty figuring out how to begin.

I just bought a carrier unlocked V405QA running V405UA20a. I see “Enable OEM Unlock” and I confirmed I can make calls with my t-mobile sim card.

My goal is to install Lineage 17.1 with root via TWRP and use it on my t-mobile account.

I was planning on following this guide then follow (this and this ) or just this one from getdroidtips.com.

Should I skip this guide and don't crossflash if I’m going to install Lineage via TWRP anyway?

Can you recommend a best approach?
[LG V40 Guides, News, & Discussion] Ainz_Ooal_Gown:
If you have a US unlocked V405QA...keep that firmware on it as it's the best one out of all the stock roms so don't cross flash...and yes follow both Xsavi and Markus' guides for bootloader unlock and TWRP flashing