Database Users

Remove ClockworkMod Recovery and relock after bricked

So I tried to update to KitKat 4.4 and was never able to get passed the loading screen. I booted into ClockworkMod Recovery and wiped everything and now the device will not go passed the Google loading screen. The device is no longer recognized when I plug into the computer and I cannot access through Wugs.
I called Google and they are sending out an RMA for this device (I did not tell them it was unlocked) and they are sending out a replacement.
Is there anyway that I can remove ClockworkMod Recovery and re-lock this device without being able to access the device through a computer?

BrianXP7 said:
Whoa, RMA's should be only used for last resort bootloader bricks! Since you still have the bootloader ("Google" logo at startup), hold Power + Volume Down to enter Fastboot mode and try reflashing the factory images. Just to be safer, use the Universal Naked Drivers and skip with bootloader image. Don't forget to have the ADB and Fastboot binaries in the same folder. I wouldn't recommend toolkits as they don't expose new users with these situations.
If you need anything else, let me know. If I completely missed on what you needed, sorry about that.
Also, just as long as the bootloader update isn't interrupted or type "fastboot erase bootloader" you should be fine without an RMA.
Click to expand...
Click to collapse
thanks for the reply.
I am able to boot in recovery mode on the device and this is recognized by Wugs as "ADB - device on". When I attempt any flash, it checks Fastboot status and I receive notification that the "Fastboot device was not found". I cannot find a compatible driver when I am in fastboot mode running on a Windows 7 x64 machine.
Any idea on how I can get this N7 to function, return to stock, or at least remove ClockworkMod and lock the bootloader so I can RMA?

Problems booting into recovery

Okay, to start with, I've read the other threads about this. I understand the process that *should* work:
1. Power off.
2. Then, press and hold both all Volume Down + Power buttons at the same time until the LG Logo is being displayed on your LG V20.
3. Now, release the keys and press the above combination again however, this time you should wait until recovery mode menu is displayed.
...and I've tried the version where you keep holding the Volume Down button the entire time.
So, yes, I've reached the white screen where it asks you if you want to do a factory reset. I've hit "Yes" to both questions. The problem is that it really does a factory reset then.
---
After unlocking the bootloader, I installed TWRP via fastboot:
adb reboot bootloader
fastboot flash recovery twrp.img
fastboot reboot
...everything went fine.
But I can't get into recovery. And since I'm waiting to have TWRP working so that I can flash root, I can't boot into recovery via an app.
What did I do wrong?
EDIT:
Okay, it looks like TWRP isn't working properly. I tried "adb reboot recovery" and that got me to a dead Android icon and a "No command" message. I have no idea why TWRP isn't working.

Haphim said:
Okay, to start with, I've read the other threads about this. I understand the process that *should* work:
1. Power off.
2. Then, press and hold both all Volume Down + Power buttons at the same time until the LG Logo is being displayed on your LG V20.
3. Now, release the keys and press the above combination again however, this time you should wait until recovery mode menu is displayed.
...and I've tried the version where you keep holding the Volume Down button the entire time.
So, yes, I've reached the white screen where it asks you if you want to do a factory reset. I've hit "Yes" to both questions. The problem is that it really does a factory reset then.
---
After unlocking the bootloader, I installed TWRP via fastboot:
adb reboot bootloader
fastboot flash recovery twrp.img
fastboot reboot
...everything went fine.
But I can't get into recovery. And since I'm waiting to have TWRP working so that I can flash root, I can't boot into recovery via an app.
What did I do wrong?
EDIT:
Okay, it looks like TWRP isn't working properly. I tried "adb reboot recovery" and that got me to a dead Android icon and a "No command" message. I have no idea why TWRP isn't working.
Click to expand...
Click to collapse
to confirm, have you verified you are using the correct TWRP version for your V20?
in this step "fastboot flash recovery twrp.img" is your twrp image that you saved, named twrp.img? If its not, that command won't work correctly.
usually after I flash recovery, when still in the recovery menu, i choose reboot recovery just to make sure it did stick. If it reboots back to itself, then try rebooting the device, and again confirm with manually entering recovery. Maybe overkill but it works for me LOL.
Good luck!

I am in need of big help! I made a critical error after days of trying to navigate the minefields of rooting my device. I have a LG V20 h910 and it is no one-click wonder root. It made me work for it and I finally got it. I loaded LineageOS 14.1 and all was good until the USB OTG cable from my PS4 controller did not register anymore. Damn, that was a let down, and probably led to my careless move of needing to downgrade my TWRP, saw the version I needed, forgot these are device specific, and now I'm stuck in a hard place.
Perhaps the fix is easy, but I have not found the answer after many, many searches...
I had TWRP 3.2.1-2 and needed to downgrade to 3.2.1-0 to try SuperRom (hoping it would have OTG ability). I hastily grabbed the first TWRP 3.2.1-0, threw it on the SD card, wiped everything except internal storage, and flashed the img, and did a reboot. Road block went up.
I tried getting back into recovery, did the PWR and DOWN pressing combo and got the Factory Reset screen, but after clicking "Yes" to both, instead of getting the TWRP screen, I got this error screen (attached).
I tried another idea - hooked it up USB to my PC and tried accessing it via adb/fastboot. I tried multiple drivers for my device, but no adb and no fastboot devices were ever found. The only thing that almost worked was booting phone into FASTBOOT mode by holding DOWN btn and plugging in a USB cable attached to PC. Once in FASTBOOT mode, My PC at least saw the ID for fastboot device. I tried to flash TWRP via fastboot, and it looked like it would happen, but in the end there was no phone screen response to my attempt, and the cmd window on my PC would get stuck and just hang.
Can someone please advise me on how I can fix this problem?

When my phone is in fastboot I don't see it on cmd "adb devices".

I tried with different drivers etc. but its just don't work, i downloaded TOOL ALL IN ONE, but this said that device was found but not said what or which device, only when phone is normally started i see it on the list of "adb devices" and in TOOL ALL IN ONE. Please help thanks in advance =)

Fastboot is an entirely different mode from adb, and as such it requires a different tool. In the console there is a command "fastboot", which is what you need to use to interact with the phone in fastboot mode. You can boot into fastboot mode from power off with the USB to computer plugged in by holding Volume Down, or it might be possible with TOOL ALL IN ONE, I haven't used it much.
Some basic commands:
fastboot flash unlock path/to/unlock.bin # This will flash the unlock bin
fastboot getvar unlocked # This will check if the device is unlocked
fastboot reboot # This will reboot the phone into normal mode, since powering off by holding the power button is a pain
To flash TWRP, there's a more advanced process with some specific requirements, but I'd be happy to share those if wanted.

mwsundberg said:
Fastboot is an entirely different mode from adb, and as such it requires a different tool. In the console there is a command "fastboot", which is what you need to use to interact with the phone in fastboot mode. You can boot into fastboot mode from power off with the USB to computer plugged in by holding Volume Down, or it might be possible with TOOL ALL IN ONE, I haven't used it much.
Some basic commands:
fastboot flash unlock path/to/unlock.bin # This will flash the unlock bin
fastboot getvar unlocked # This will check if the device is unlocked
fastboot reboot # This will reboot the phone into normal mode, since powering off by holding the power button is a pain
To flash TWRP, there's a more advanced process with some specific requirements, but I'd be happy to share those if wanted.
Click to expand...
Click to collapse
Yeah, so I wanted to flash TWRP but it doesen't seem to work i did what was said in many guides but maybe if you tell me how to do it, it will work =) Thanks
So i tried to flash TWRP with the TOOL ALL IN ONE, everything was okey but then error happened called "Unknown device"

First of all, which version of G6 do you have? The US997 one, or the H870?

mwsundberg said:
First of all, which version of G6 do you have? The US997 one, or the H870?
Click to expand...
Click to collapse
H870

For H870 I'm not entirely sure, but I know that for the US997 you have to do a special procedure to make it permanent. Make sure you back up everything first, too.
With the phone in fastboot mode and a computer connected with fastboot installed and the twrp zip downloaded as "twrp.zip" (or whatever you want):
Make sure the bootloader is unlocked: fastboot getvar unlocked (should return "yes" or "true").
Flash the recovery: fastboot flash recovery twrp.zip (replace twrp.zip with the relative or absolute filepath/name).
Unplug the phone from the computer and reboot into recovery by holding Power and Volume Down. When the logo appears, lift your finger off the power button briefly and then continue pressing.
When you get to the factory reset menu hit yes twice, then the phone should boot into twrp (it may flash the LG logo, I've had different behavior on different phones. You won't need to hold the Power-Volume Down combo any more).
In twrp, swipe to allow modification, then in the Wipe menu select Format Data (and enter yes). This will wipe the phone, so make sure everything was backed up beforehand.
From the main menu go to the Reboot menu and select Recovery.
Here it might vary from the US997. Below are suggestions which I think are needed to have it work.
Download the no-verity-opt-encrypt zip, and connect the phone to the computer.
Once it's rebooted into recovery mode: adb push path/to/no-verity.zip /sdcard/
Then from the install menu in twrp install the zip.
Reboot into System from the reboot menu on the homescreen of twrp.
That should do it all.

phone bricked? help!

I decided to update my old oneplus 2 to lineageos 15.1 with, but when I tried to flash the file with TWRP, it shows an error. Since the TWRP version I was using was old, I decided to update it first. Keep in mind at this point i had completely wiped my device. So, I downloaded the "twrp-3.2.1-0-kenzo.img" file, as per a youtube video where the dude managed to flash the update successfully, and gave it a go. It showed up as successful. Then i shut the whole device off, and tried to boot back in to recovery to flash the ROM again, but the thing won't boot. It's stuck on this boot screen (with the oneplus logo and 'powered by android' at the bottom), and refuses to go further. I'm stuck in a situation with the phone having no OS, no recovery and the thing won't show up when I connect it to the pc either. Well, the pc makes the 'device connected' notification sound when I plug it in, but nothing shows up on the file explorer or the device manager.
That's my dilemma, please i need help!
Thanks in advance.

inwarse said:
I decided to update my old oneplus 2 to lineageos 15.1 with, but when I tried to flash the file with TWRP, it shows an error. Since the TWRP version I was using was old, I decided to update it first. Keep in mind at this point i had completely wiped my device. So, I downloaded the "twrp-3.2.1-0-kenzo.img" file, as per a youtube video where the dude managed to flash the update successfully, and gave it a go. It showed up as successful. Then i shut the whole device off, and tried to boot back in to recovery to flash the ROM again, but the thing won't boot. It's stuck on this boot screen (with the oneplus logo and 'powered by android' at the bottom), and refuses to go further. I'm stuck in a situation with the phone having no OS, no recovery and the thing won't show up when I connect it to the pc either. Well, the pc makes the 'device connected' notification sound when I plug it in, but nothing shows up on the file explorer or the device manager.
That's my dilemma, please i need help!
Thanks in advance.
Click to expand...
Click to collapse
You downloaded the KENZO (this is not oneplus2! ) TWRP and flashed it on another phone (oneplus2), just normal that it doesn't work and your phone is messed up.
If you can enter fastboot (vol up and power button to boot) you can rescue your phone:
-enter fastboot (vol up + power, while phone is completely off, u can also hold it until you can see "fastboot" written on the screen)
-connect device to a computer with fastboot installed
-type "fastboot oem unlock" into a terminal/cmd window if there is no error, you are good to go, otherwise your bootloader relocked, use this thread to recover
-if your bootloader is still unlocked, download the ONEPLUS2 TWRP IMG, ALWAYS make sure to only flash the roms, kernels, recoveries or zips for YOUR phone otherwise you can really DESTROY your phone!
-now type into terminal/cmd: "fastboot flash recovery *drag the oneplus2 twrp image into terminal/cmd window* and hit enter
-use vol down + power to reboot phone into recovery and wipe all partitions
-Install a ONEPLUS2 ROM of your choice
If something is not clear, use google, because this is most likely basic stuff you have to know when flashing your phone

I can in fact go to fastboot mode by holding the power+volume up keys. When I the phone to my pc it does show a fastboot device (9597b869 fastboot). What do i do from here?

inwarse said:
I can in fact go to fastboot mode by holding the power+volume up keys. When I the phone to my pc it does show a fastboot device (9597b869 fastboot). What do i do from here?
Click to expand...
Click to collapse
As I wrote above (it's a step-by-step guide, u only have to READ )
-connect device to a computer with fastboot installed
-type "fastboot oem unlock" into a terminal/cmd window if there is no error, you are good to go, otherwise your bootloader relocked, use this thread to recover
-if your bootloader is still unlocked, download the ONEPLUS2 TWRP IMG, ALWAYS make sure to only flash the roms, kernels, recoveries or zips for YOUR phone otherwise you can really DESTROY your phone!
-now type into terminal/cmd: "fastboot flash recovery *drag the oneplus2 twrp image into terminal/cmd window* and hit enter
-use vol down + power to reboot phone into recovery and wipe all partitions
-Install a ONEPLUS2 ROM of your choice

wertus33333 said:
As I wrote above (it's a step-by-step guide, u only have to READ )
-connect device to a computer with fastboot installed
-type "fastboot oem unlock" into a terminal/cmd window if there is no error, you are good to go, otherwise your bootloader relocked, use this thread to recover
-if your bootloader is still unlocked, download the ONEPLUS2 TWRP IMG, ALWAYS make sure to only flash the roms, kernels, recoveries or zips for YOUR phone otherwise you can really DESTROY your phone!
-now type into terminal/cmd: "fastboot flash recovery *drag the oneplus2 twrp image into terminal/cmd window* and hit enter
-use vol down + power to reboot phone into recovery and wipe all partitions
-Install a ONEPLUS2 ROM of your choice
Click to expand...
Click to collapse
i tried to follow the guide. but the bootloader, as per you description is relocked. the download link for the driver you provided shows up as empty/no longer available. that's where i'm getting stuck.
P.S, i can enter fastboot mode on the phone via power+volume up.
thanks for the help so far, i can't seem to find much help other than from you so far

Oh, the link is dead, sry for that. try this one (GDrive links are up and working).

inwarse said:
i tried to follow the guide. but the bootloader, as per you description is relocked. the download link for the driver you provided shows up as empty/no longer available. that's where i'm getting stuck.
P.S, i can enter fastboot mode on the phone via power+volume up.
thanks for the help so far, i can't seem to find much help other than from you so far
Click to expand...
Click to collapse
so i managed to get into qualcomm mode, updated the drivers, and ran "MSM8994DownloadTool.exe" in administrator mode. it went as it's outlined in your guide. however, at the end of that process, the phone got stuck in a bootloop (the oneplus logo flashes for a moment and restarts). and can't get into qualcomm mode now, since when i connect the usb to the pc while the phone off, it lights the display (to show that it's charging, i think). any way back from this?
(i can still get into fastboot mode)

inwarse said:
so i managed to get into qualcomm mode, updated the drivers, and ran "MSM8994DownloadTool.exe" in administrator mode. it went as it's outlined in your guide. however, at the end of that process, the phone got stuck in a bootloop (the oneplus logo flashes for a moment and restarts). and can't get into qualcomm mode now, since when i connect the usb to the pc while the phone off, it lights the display (to show that it's charging, i think). any way back from this?
(i can still get into fastboot mode)
Click to expand...
Click to collapse
Do you still have TWRP? If yes go to TWRP and shut down the phone there, afterwards you should be able to enter qualcomm mode again.
otherwise you have to try (i think 10s power button will shut the device completely down). You should be able to enter qualcomm mode if the device is fully shut off (your scenario sounds as if the device is not fully shut off when u connect it to the pc).
Just to go sure: You are absolutely sure to have a oneplus2, are you?

inwarse said:
so i managed to get into qualcomm mode, updated the drivers, and ran "MSM8994DownloadTool.exe" in administrator mode. it went as it's outlined in your guide. however, at the end of that process, the phone got stuck in a bootloop (the oneplus logo flashes for a moment and restarts). and can't get into qualcomm mode now, since when i connect the usb to the pc while the phone off, it lights the display (to show that it's charging, i think). any way back from this?
(i can still get into fastboot mode)
Click to expand...
Click to collapse
Could you resolve the issue?

wertus33333 said:
Could you resolve the issue?
Click to expand...
Click to collapse
nope. kept running into issue after issue, so got dejected and gave up.

Nexus 7 2012 stuck in APX mode

I presume I'm stuck, but just in case…
I used TWRP to flash the latest LineageOS, and for some reason the bootloader got erased/corrupted (I'm not entirely sure how this can happen).
As a result, the tablet is now stuck in APX mode when booting up. Inconvenient to say the least…
I can still access TWRP, but any attempt to access Fastboot (ie adb reboot bootloader) results into the unit getting into NVIDIA recovery mode (ie APX)
And of course I don't have a backup of the boot keys.
Since I can access TWRP, is there anyway I can get access to the boot keys to reconstruct my bootloader ?
Regards

Ashram56 said:
I presume I'm stuck, but just in case…
I used TWRP to flash the latest LineageOS, and for some reason the bootloader got erased/corrupted (I'm not entirely sure how this can happen).
As a result, the tablet is now stuck in APX mode when booting up. Inconvenient to say the least…
I can still access TWRP, but any attempt to access Fastboot (ie adb reboot bootloader) results into the unit getting into NVIDIA recovery mode (ie APX)
And of course I don't have a backup of the boot keys.
Since I can access TWRP, is there anyway I can get access to the boot keys to reconstruct my bootloader ?
Regards
Click to expand...
Click to collapse
Hi, Ashram56...
Just to confirm, we are talking about the Nexus 7 (2012) tablet here? Because if you can still access TWRP, the bootloader is not 'dead'. If the bootloader were corrupted or erased, the device would not boot at all... ever! Not even in TWRP!
If it is a Nexus 7, you should be able to manually boot the device into its bootloader by long pressing and holding the volume down button, and at the same time, press the power button.
With regard to doing it via a command prompt, I think you need...
Code:
fastboot reboot bootloader
...as ADB commands only work when Android is fully booted.
Hope this helps.
Rgrds,
Ged.

GedBlake said:
Hi, Ashram56...
Just to confirm, we are talking about the Nexus 7 (2012) tablet here? Because if you can still access TWRP, the bootloader is not 'dead'. If the bootloader were corrupted or erased, the device would not boot at all... ever! Not even in TWRP!
If it is a Nexus 7, you should be able to manually boot the device into its bootloader by long pressing and holding the volume down button, and at the same time, press the power button.
With regard to doing it via a command prompt, I think you need...
Code:
fastboot reboot bootloader
...as ADB commands only work when Android is fully booted.
Hope this helps.
Rgrds,
Ged.
Click to expand...
Click to collapse
Yes this is a Nexus 7 2012
However that's the point: I can boot TWRP (hence adb mode), however if I select "adb reboot bootloader", or if I select "Bootloader" using the Power+Volume Down menu, I don't get into fastboot, I only get into APX, which is recovery
I was under the impression that the bootloader was corrupted, I'm glad this is not the case. Now I just need to figure out how to recover from where I am at this point

And to clarify even further:
- I tried to use TWRP to flash boot.img that I extracted from LineageOS, still boots into recovery
- Did the same with the recovery image, same behaviour
- I realized that I had performed (my bad) a complete "internal storage" wipe, after flashing originally, which might have caused the issue
Bootloader indeed seems to be intact, the info page on the recovery menu (ie before booting TWRP) states 4.23

Ashram56 said:
Yes this is a Nexus 7 2012
However that's the point: I can boot TWRP (hence adb mode), however if I select "adb reboot bootloader", or if I select "Bootloader" using the Power+Volume Down menu, I don't get into fastboot, I only get into APX, which is recovery
I was under the impression that the bootloader was corrupted, I'm glad this is not the case. Now I just need to figure out how to recover from where I am at this point
Click to expand...
Click to collapse
I suspect some confusion of technical terms is going on here.
Can you as describe, as precisely as possible, exactly what your Nexus 7 is displaying, when you enter what you think is, or might be, APX mode.
A picture/photograph would be even better.
APX/nvFlash mode is NOT Recovery. These are very, very different things.
Recovery is either the devices Stock Recovery, or a Custom Recovery, such as TWRP or CWM.
Rgrds,
Ged.
---------- Post added at 07:07 PM ---------- Previous post was at 06:52 PM ----------
Ashram56 said:
And to clarify even further:
- I tried to use TWRP to flash boot.img that I extracted from LineageOS, still boots into recovery
- Did the same with the recovery image, same behaviour
- I realized that I had performed (my bad) a complete "internal storage" wipe, after flashing originally, which might have caused the issue
Bootloader indeed seems to be intact, the info page on the recovery menu (ie before booting TWRP) states 4.23
Click to expand...
Click to collapse
OK, just seen this post.
You dont use TWRP to flash .img files, you use fastboot, so for example, you'd use the following command lines...
Code:
fastboot flash boot [name-of-boot-file].img
...or...
Code:
fastboot flash recovery [name-of-recovery-file].img
...with the Nexus 7 booted into fastboot mode and USB connected to a laptop or a PC.
Rgrds,
Ged.

Hi, again Ashram56...
Some further thoughts regarding your situation...
Ashram56 said:
Bootloader indeed seems to be intact, the info page on the recovery menu (ie before booting TWRP) states 4.23
Click to expand...
Click to collapse
So that would be on the fastboot menu then, and not the recovery menu. I'm not trying to be needlessly pedantic here, but when dealing with this kind of thing, and when asking for advice, it's important to use the correct terms, otherwise confusion can arise.
Anyhow, your reporting of this indicates that your Nexus 7's bootloader is alive and well, which means the device is almost certainly recoverable.
Furthermore, bootloader v4.23 is the latest and the very last bootloader version this device will ever receive.
Whatever you chose to do, I'd strongly recommend against reflashing the bootloader again, as this process is the 'Achilles Heel' of the Nexus 7, and it's a potential terminal weakness. A bad bootloader flash, perhaps via a dodgy USB connection, can corrupt the bootloader, and render the device permanently hardbricked. And the only realistic solution to that is a motherboard replacement.
And which brings me to this...
Ashram56 said:
And of course I don't have a backup of the boot keys.
Since I can access TWRP, is there anyway I can get access to the boot keys to reconstruct my bootloader ?
Click to expand...
Click to collapse
I'm aware that you mentioned in your original post, something you called 'boot keys'. I assume you refer to the Nexus 7 'flatline' procedure for generating bootloader 'blobs', described here...
https://forum.xda-developers.com/showthread.php?t=2455927
Such 'blobs' can ONLY be used on the original Nexus 7 with which they were originally generated. They are NOT transferable from one N7 to another N7.
Running the 'flatline' procedure is a fairly high risk venture, and requires a good knowledge and a high level of familiarity with using fastboot commands, because it involves flashing a special build of the bootloader. I ran it myself, a few years ago, and it's a pretty nerve wracking experience, wondering if your Nexus 7 will ever boot again!
Mine did, and I now have my N7 bootloader 'blobs', stored on my laptop ~ but I have absolutely no idea at all, if they'd be of any use should I have need to dig myself out of an APX shaped hole!
Fortunately that hasn't happened yet, and my 'blobs' will now likely forever remain untested, as I rarely use my Nexus 7 these days.
------------------------------------
Ashram56 said:
I used TWRP to flash the latest LineageOS, and for some reason the bootloader got erased/corrupted (I'm not entirely sure how this can happen
Click to expand...
Click to collapse
...And it can't happen!. A TWRP flash of a Custom ROM, such as LineageOS, goes nowhere near the bootloader partition. It doesn't touch it at all. Same with a TWRP Nandroid restore. Bootloader partition is left alone, unmodified and untouched.
------------------------------------
Anyhow, and in conclusion, it sounds like your bootloader is still working, and you should therefore be able to recover the device.
The easiest way of doing this, is to download a Google Factory Stock image for the Nexus 7 and flash it via fastboot, and which you can find here...
https://developers.google.com/android/images#nakasi
------------------------------------
Good luck with getting your Nexus 7 up and running again, and I hope this helps.
Rgrds,
Ged.

You are correct to ask to be very precise, as words have different meaning, and can lead to confusion, as is the case here
I used the word "recovery" by mistake (I'm actually in HW Embedded design, and APX mode is called "recovery" mode in a lot of Tegra related literature). So to be clear, I will only refer to APX mode.
APX mode is essentially a mode the chip enters when it cannot find a valid bootloader, or when the bootloader fails to load a valid kernel (see similar details here for those who really want to get their head spinning: http://developer.nvidia.com/embedded/dlc/jetson-fuse-burning-secure-boot-28-2-ga , need registration to access the document though). You can also access this mode by asserting some HW pins at boot up (which are not exposed on the Nexus 7 2012 anyway)
Screen is black in this case, since the kernel has not loaded
Symptoms I have:
- I can access the "Boot select" menu, through Power+Volume- menu
- I can access from the "Recovery", which launches TWRP
- If I use the "Reboot" option from TWRP, or the "Bootloader" option from the "Boot select" menu in 1/, I get a black screen, and the tablet appears to be in APX mode (seen through simple linux lsusb command)
It turns out that in "some" instances I was able to actually turn on the tablet and boot the OS, but I can't figure what sequences (ie I can't find a reproducible way of booting correctly, 9 times out of 10 I get into APX mode).
I'll try to figure out further what the heck is going on. My suspicion is that the bootloader is attempting to load the kernel, and the first copy is corrupted. In most Tegra implementations, this should be covered through redudancy of the kernel at multiple locations (same for bootloader actually), but I'm not knowledgeable enough about Android to determine if this is the case as well here.
Thanks for the help in any case

And to add to that:
when in "Boot select" menu, units does appear in Fastboot mode, however "fastboot reboot bootloader" gets me into APX mode (black screen, tablet seen as APX device, fastboot and adb not functional), same as booting to Bootloader from TWRP or "select" menu.
I'm quite puzzled...

Just a note: one time out of 10 I can boot into the OS
I'll settle for that for the moment

Reviving this 4y old thread...
So, recently I unburied my Nexus 7, to use it as a secondary device for some home automation application.
Took me a while to find my bearings again, but here's a summary of where I stand:
- If I power on normally (ie power button) the tablet for the first time or do a reboot (either through the UI or the adb command), it enters "NVIDIA Tegra recovery mode", ie device driver appears as APX
- When is this mode, if I press the power button for 10s or so it powers off
- When fully off, if I simultaneously press Volume - + power button, I can enter the bootloader mode (ie Fastboot mode), with the small droid, the info text at the bottom left, and a big "Start" button on the upper right corner.
Info reported in the bottom left in that case:
Fastboot mode
Product name - grouper
Variant name - grouper
HW version - ER3
Bootloader version - 4.23
Basedband version - N/A
Serial Number - sequence of numbers
Signing - not defined yet
Lock state - Unlocked
- in this mode, the volume keys do not have any effect, I can't select anything, only "Start" is available. I can indeed "Start" the tablet using the power button
It starts Android (in my case LineageOS), but in safe mode only, so limited functionality
And I'm stuck, since I can't use the tablet.
I know it's a very old thread, but if anyone has any clue on how to resolve this, I'm interested
Regards
[EDIT] Some additionnal data
- First, looks like my volume buttons are actually broken. I don't get any response inside Android UI, that would explain why I can't select anything in when in fastboot besides "Start" option
- I reverted back to the stock image, but I'm still stuck in safe mode.
I can't install LineageOS back, since I can't navigate in fastboot menu and access twrp (unless I can do that using a fastboot command) ?