[Nexus 7 (2013) Q&A] omaquaire:
Dear all,

This is my first message on this forum, so thank you for letting me join. I hope we can fix my current problem.

Quickly, about the context, I got a Nexus 7 2013 LTE from a colleague who kinda bricked it. Apparently, he has been investigating on it for some time, so I am completely unsure what happened. I'll do my best to provide answers and perform actions but there are some things I do not know, and some other things I might not be able to do.

About the tablet, as aforementioned, it is a Nexus 7 2013 LTE from Asus/Google, and my friend told me it is 2nd generation.

The tablet cannot boot at all, only got the white Google logo, thus I am unsure what is currently installed.

Same with recovery mode unavailable, anyway I can access the fastboot mode (volume down + power) where I could get the following information :

Product name : deb
Variant : deb 32G
HW version : rev_e
Bootloader version : FLO-04.05
Baseband version : DEB-Z00_2.44.0_0213
Carrier info : None
Serial number : 05ef14bb
Signing : Yes
Secure boot : Enabled
Lock state : Locked

As the OS is not booting, I am figuring out to reinstall the OS from scratch using an Android official image gathered here :

https://developers.google.com/android/nexus/images#razorg

I downloaded the latest razorg

Question :

Can you please confirm that his choice is correct ?

Then I also installed the latest android SDK.

I had a little trouble to get the driver installed, but finally, and when fastbooted, the windows device manager shows :

Android device
[INDENT]Android Bootloader Interface[/INDENT]

When running fastboot commands, I get the following :

C:\Program Files (x86)\Android\android-sdk\platform-tools>fastboot devices
05ef14bb fastboot
C:\Program Files (x86)\Android\android-sdk\platform-tools>fastboot oem device-info
...
(bootloader) Device tampered: false
(bootloader) Device unlocked: false
(bootloader) SB=Y
OKAY [ 0.012s]
finished. total time: 0.014s

So my assumption is that so far my setup is correct.

Question :

Can you please confirm ?

Now coming back to the procedure to perform the update, we roughly got the following :

- Get the image

- Get the latest android SDK

- Run a fastboot oem unlock to allow the firmware to be updated

- Run the flash-all.bat command which will perform

* Flash of the bootloader

* Flash of the radio

* Update of the OS
​

- Run a fastboot oem lock to prevent any further update.

Right now I am trying to run a fastboot oem unlock.

I get the confirmation screen on the device about removing all personal data.

I can confirm and then the process is starting, or is supposed to start since I get the following output :

C:\Program Files (x86)\Android\android-sdk\platform-tools>fastboot oem unlock
...
(bootloader) Unlocking bootloader...
(bootloader) erasing userdata...

Anyway, after several tries, and ultimately around 12 hours letting it work, I need to observe that the device is not yet unlocked.

I also tried a

C:\Program Files (x86)\Android\android-sdk\platform-tools>fastboot erase cache
******** Did you mean to fastboot format this partition?
erasing 'cache'...

Anyway it stays stuck.

I also tried to format the cache, but due to the fact that the system is still in a locked state, it is not possible.

C:\Program Files (x86)\Android\android-sdk\platform-tools>fastboot format cache -u
Creating filesystem with parameters:
Size: 587202560
Block size: 4096
Blocks per group: 32768
Inodes per group: 7168
Inode size: 256
Journal blocks: 2240
Label:
Blocks: 143360
Block groups: 5
Reserved block group size: 39
Created filesystem with 11/35840 inodes and 4616/143360 blocks
sending 'cache' (10984 KB)...
FAILED (remote: Bootloader is locked.)
finished. total time: 0.011s

So my questions are :

- Was everything done correctly ?

- Have you got any idea on how to make it work ?

I'd like to add that I read numerous posts about those kind of issues, but could not find anything satisfactory.

I read that it might be needed to activate the debug mode, and some unlock within the development menu, anyway and as previously mentioned I do not have access to the OS, so I do not know if those changes are done, and also cannot perform anything.

As mentioned the fastboot is working, about ADB it is not, but I also believe that ADB can only be used while the main OS is started (as opposed with fastboot mode), and development option / debugging option are activated.

Is this assumption correct ?

Thank you for your help in advance.