collapse

Author Topic: N7 (2012) stuck in APX mode with corrupted bootloader  (Read 24451 times)

Offline birdastrompgman

  • Hero Member
  • *****
  • Posts: 840
  • Popularity: 28
    • View Profile
N7 (2012) stuck in APX mode with corrupted bootloader
« on: March 17, 2014, 12:24:05 AM »
My N7 wasn't responding in an app, so I powered it off.  Since then, it won't power back up.  I've tried holding the power button for more than 60 seconds, and I've tried powering it on into Recovery with the  power and volume buttons, unsuccessfully. 

I hooked it up to my PC and discovered I can put it in APX mode by pushing the power button.  The N7 gives no visible sign of turning on, but Win7 sees it as an APX device when I toggle the power button.

Apparently my Bootloader is corrupted, as the only repeatable method of entering APX mode is by erasing the bootloader.  The only way to fix it is to find a version of NVFlash for the N7 and reflash my bootloader, per this discussion..  I'll need some time to figure out how to recover my device.

N7 (2012), rooted, running Android 4.4.2. Out of warranty, of course.

I anyone has experience with this, or understands what steps I need to take, please tell me in this thread, or direct me to where this has been discussed/fixed.  TIA.

Best


Bird has seen >650 North American bird species
Rooted Nexus 7
49.5 mpg avg for 53k miles in non-hybrid Scion xB
Retired 9 yrs, and loving it

Offline birdastrompgman

  • Hero Member
  • *****
  • Posts: 840
  • Popularity: 28
    • View Profile
Re: N7 (2012) stuck in APX mode with corrupted bootloader
« Reply #1 on: March 17, 2014, 12:31:40 AM »
If any N7 (2012) owner is willing to make a set of the needed img files from the previous link for me to restore my N7, I'd greatly appreciate your help!

Quote
For Nexus 7, we recommend backing up the following partitions:
$ nvflash --resume --read 5 eks.img
$ nvflash --resume --read 13 factory-config.img
$ nvflash --resume --read 14 mda.img
« Last Edit: March 17, 2014, 12:44:34 AM by birdastrompgman »
Bird has seen >650 North American bird species
Rooted Nexus 7
49.5 mpg avg for 53k miles in non-hybrid Scion xB
Retired 9 yrs, and loving it

Offline matt

  • Hero Member
  • *****
  • Posts: 936
  • Popularity: 28
    • View Profile
Re: N7 (2012) stuck in APX mode with corrupted bootloader
« Reply #2 on: March 17, 2014, 07:04:23 AM »
From what I'm seeing, the blob files need to be created by the original device.

http://forum.xda-developers.com/showthread.php?t=1879228

Hard brick, damn.

Sent from my Nexus 7 using Tapatalk


Offline birdastrompgman

  • Hero Member
  • *****
  • Posts: 840
  • Popularity: 28
    • View Profile
Re: N7 (2012) stuck in APX mode with corrupted bootloader
« Reply #3 on: March 17, 2014, 10:07:12 AM »
It's a bummer, for sure.  I think I can reflash the bootloader, and use fastboot commands to rebuild the firmware/software.  I have nothing to lose.
Bird has seen >650 North American bird species
Rooted Nexus 7
49.5 mpg avg for 53k miles in non-hybrid Scion xB
Retired 9 yrs, and loving it

Offline matt

  • Hero Member
  • *****
  • Posts: 936
  • Popularity: 28
    • View Profile
Re: N7 (2012) stuck in APX mode with corrupted bootloader
« Reply #4 on: March 17, 2014, 04:57:16 PM »
Looks like dhsub is the Qualcomm driver for the 2013. Some talk of JTAG repair, soldering to motherboard. No solutions yet.

I'm thinking the memory got corrupted, when flashing a ROM from working fastboot, the nands must be reformatted and bad blocks logged.

If the hynix chips are going, you might find one with a broken screen and swap the main board.

Sent from my Nexus 7 using Tapatalk


Offline matt

  • Hero Member
  • *****
  • Posts: 936
  • Popularity: 28
    • View Profile
Re: N7 (2012) stuck in APX mode with corrupted bootloader
« Reply #5 on: March 17, 2014, 07:01:21 PM »
http://forum.xda-developers.com/showthread.php?t=2244413

Someone got out of apx.

Sent from my Nexus 7 using Tapatalk


Offline birdastrompgman

  • Hero Member
  • *****
  • Posts: 840
  • Popularity: 28
    • View Profile
Re: N7 (2012) stuck in APX mode with corrupted bootloader
« Reply #6 on: March 17, 2014, 11:34:52 PM »
http://forum.xda-developers.com/showthread.php?t=2244413

Someone got out of apx.

Sent from my Nexus 7 using Tapatalk


Info in that link (recovery reboot) didn't work for me.  I'll be home tomorrow, and hope to tackle the bootloader reflash then.
Bird has seen >650 North American bird species
Rooted Nexus 7
49.5 mpg avg for 53k miles in non-hybrid Scion xB
Retired 9 yrs, and loving it

Offline birdastrompgman

  • Hero Member
  • *****
  • Posts: 840
  • Popularity: 28
    • View Profile
Re: N7 (2012) stuck in APX mode with corrupted bootloader
« Reply #7 on: March 18, 2014, 10:46:23 PM »
I'm going to generate my blob files from my stepdaughter's N7 [2012].  I'll downgrade its OS to Android 4.1.2, since the NVFlash bootloader image is 4.1.3 (it's running 4.4.2 currently).  Hopefully, I'll be able to report some progress tomorrow.  I'm backing up her data right now.
Bird has seen >650 North American bird species
Rooted Nexus 7
49.5 mpg avg for 53k miles in non-hybrid Scion xB
Retired 9 yrs, and loving it

Offline birdastrompgman

  • Hero Member
  • *****
  • Posts: 840
  • Popularity: 28
    • View Profile
Re: N7 (2012) stuck in APX mode with corrupted bootloader
« Reply #8 on: March 19, 2014, 01:15:08 PM »
Ouch!  Reflashing the blob.bin bootloader failed because my chip UIDs are different between the two N7s.  Unless the chip UID is stored unencrypted in open view (highly unlikely in a binary file), I'm hosed.

All I  can say, guys, is make your blob files now, before you find yourselves in my situation!
Bird has seen >650 North American bird species
Rooted Nexus 7
49.5 mpg avg for 53k miles in non-hybrid Scion xB
Retired 9 yrs, and loving it

Offline matt

  • Hero Member
  • *****
  • Posts: 936
  • Popularity: 28
    • View Profile
Re: N7 (2012) stuck in APX mode with corrupted bootloader
« Reply #9 on: March 19, 2014, 01:35:25 PM »
What I'm wondering, is the root cause. Static discharge to the USB port, cosmic rays or em pulse, or faulty chips? If the latter, might cut your losses and part out. The former, wait for a hacked nvflash that doesn't use so much security.


Sent from my Nexus 7 using Tapatalk


Offline birdastrompgman

  • Hero Member
  • *****
  • Posts: 840
  • Popularity: 28
    • View Profile
Re: N7 (2012) stuck in APX mode with corrupted bootloader
« Reply #10 on: March 19, 2014, 04:31:38 PM »
My WAG is a cosmic ray glitch.  I wasn't doing anything unusual,  not walking in wool socks, not near loudspeakers or magnets, didn't drop it, etc.

My son dropped his 8GB N7 (2012) and cracked its screen.  I guess that'll be the best use for the parts.
Bird has seen >650 North American bird species
Rooted Nexus 7
49.5 mpg avg for 53k miles in non-hybrid Scion xB
Retired 9 yrs, and loving it

Offline matt

  • Hero Member
  • *****
  • Posts: 936
  • Popularity: 28
    • View Profile
Re: N7 (2012) stuck in APX mode with corrupted bootloader
« Reply #11 on: March 19, 2014, 05:19:00 PM »
I'm leaning to some bad chips in the production line. The units RMA'd to Asus for this condition coming back with new main boards. (Left out solar flare)

Sent from my Nexus 7 using Tapatalk


Offline birdastrompgman

  • Hero Member
  • *****
  • Posts: 840
  • Popularity: 28
    • View Profile
Re: N7 (2012) stuck in APX mode with corrupted bootloader
« Reply #12 on: March 19, 2014, 06:37:50 PM »
I purchased the N7 1 March 2013, so it died barely 15 days past the warranty expiration.  If there are a lot of units being returned with this problem, and motherboards are being replaced, I'll buy the bad chip theory.  It might also explain the $213 repair estimate I received from Asus for what I thought was a software installation.
Bird has seen >650 North American bird species
Rooted Nexus 7
49.5 mpg avg for 53k miles in non-hybrid Scion xB
Retired 9 yrs, and loving it

Offline matt

  • Hero Member
  • *****
  • Posts: 936
  • Popularity: 28
    • View Profile
Re: N7 (2012) stuck in APX mode with corrupted bootloader
« Reply #13 on: March 19, 2014, 07:41:00 PM »
The bad units seem to be a small percentage, and perhaps only the 16gb. Waiting for mine to bite the dust, lol.

Sent from my Nexus 7 using Tapatalk


Offline birdastrompgman

  • Hero Member
  • *****
  • Posts: 840
  • Popularity: 28
    • View Profile
Re: N7 (2012) stuck in APX mode with corrupted bootloader
« Reply #14 on: March 20, 2014, 08:21:38 AM »
Well, mine is, or was a 32 GB model.  I guess I'll be buying a 2013 model by the end of the week.
Bird has seen >650 North American bird species
Rooted Nexus 7
49.5 mpg avg for 53k miles in non-hybrid Scion xB
Retired 9 yrs, and loving it

 


* Top Boards

* 'Like' And 'Follow' Us!

* Top Posters

bjs229 bjs229
2682 Posts
JayJ JayJ
2100 Posts
S.Prime S.Prime
2017 Posts
Babyfacemagee Babyfacemagee
1260 Posts
matt matt
936 Posts
birdastrompgman birdastrompgman
840 Posts
loociddreemr loociddreemr
708 Posts