# [Bootloader] JZO54K Bootloader



## winner00

Mod Type:: Mod

Difficulty:: Easy

Mod Status:: Stable

Apply In:: CWM Recovery

Carrier:: N/A (WiFi)

Requires Root:: Yes

Source:: 
Here is the bootloader in a zip that can be flashed over anything.

I recommend flashing this because it fixes the issue where you couldn't boot into recovery from the bootloader.

Download (Mediafire)
Download (Goo.im)

MD5: a8715642fcb0400579dde21b5e4cc673


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## davehasninjas

Nice, does this mean we can expect a ROM at some point as well?

Either way, thanks for the bootloader, it'll be nice to actually be able to boot to recovery without having to first power on

Sent from my Galaxy Nexus using RootzWiki


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## Ghub1

I just installed the new bootloader and still wouldn't let me boot into recovery from the bootloader. 
Sent from my Nexus 7


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## Gunthermic

Worked great.. Able to go to recovery from Bootloader now!!!


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## ROM_Ulan

Yay! This is awesome!

Edit: Still can't get into recovery from the bootloader. :-(

Sent from my Nexus 7 using Tapatalk 2


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## Mustang302LX

Should just be 3.41 from the OTA right?


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## ROM_Ulan

Mustang302LX said:


> Should just be 3.41 from the OTA right?


That's right. The mediafire one didn't work for me. After I flashed it my bootloader version was 3.34. After flashing the goo.im download it showed 3.41 and now can get to recovery from the bootloader.

Sent from my Nexus 7 using Tapatalk 2


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## Mustang302LX

ROM_Ulan said:


> That's right. The mediafire one didn't work for me. After I flashed it my bootloader version was 3.34. After flashing the goo.im download it showed 3.41 and now can get to recovery from the bootloader.
> 
> Sent from my Nexus 7 using Tapatalk 2


Yeah I flashed the update and rebooted to bootloader when I saw this post to try and then reboot to recovery which worked 3 times in a row. So if you manually flashed the update or got the OTA already you already have this new bootloader just as an FYI for others.


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## heath2805

Mustang302LX said:


> Yeah I flashed the update and rebooted to bootloader when I saw this post to try and then reboot to recovery which worked 3 times in a row. So if you manually flashed the update or got the OTA already you already have this new bootloader just as an FYI for others.


I'm rooted and have the latest version of stock, but when selecting recovery from bootloader it just sits with Google icon until powering down. I might have to download this 

Sent from my ADR6400L using Tapatalk 2


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## camblue

Works perfect thank God no more boot looping when trying to go into CWM from a cold boot! THANK YOU!!!!!


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## Mustang302LX

heath2805 said:


> I'm rooted and have the latest version of stock, but when selecting recovery from bootloader it just sits with Google icon until powering down. I might have to download this
> 
> Sent from my ADR6400L using Tapatalk 2


I didn't flash the bootloader separate ..I simply installed the 4.1.2 OTA from Google and it fixed the ability to boot to recovery from the bootloader as the OTA includes the new bootloader.


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## masully84

Thanks for posting this man, flashed with no problems.

Sent from my Nexus 7


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## wigsplittinhatchet

Boot loops for me. Md5 is good and bootloader updates to 3.41 but bootloops when trying to do anything. Tried on aokp and a stock backup using twrp.


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## Travisdroid

Worked perfect with twrp and verified it fixed the recovery issue and no boot loops here. Used the goo download.


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## Jubakuba

Mustang302LX said:


> Yeah I flashed the update and rebooted to bootloader when I saw this post to try and then reboot to recovery which worked 3 times in a row. So if you manually flashed the update or got the OTA already you already have this new bootloader just as an FYI for others.


Unfortunately, the bootloader update was a /patch/ so it wasn't the full .img.
This is perfect for me.
Flashed this bad boy.
Thanks sir.
That recovery issue was getting annoying...and this is the first post I've found with the full bootloader.img.


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## BarberAE

wigsplittinhatchet said:


> Boot loops for me. Md5 is good and bootloader updates to 3.41 but bootloops when trying to do anything. Tried on aokp and a stock backup using twrp.


Same here. AOKP and TWRP too. Mediafire download and MD5 matched.


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## BarberAE

Can't get this to work unless I stick with stock unrooted. Harware Varient ER3


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## azdave

worked great..thanks..flashed with cwm running paranoid android rom..no more boot loops going to recovery..awesome..bootloops were annoying indeed...


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## thephased

Applied this in cwm. Booted into the bootloader and went to recovery. worked. no issues. Finally nice to see we can get into recovery without adb or terminal emulator.


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## heath2805

Worked great...Thanks so much!!

Sent from my Nexus 7 using Tapatalk 2


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## kbluhm

Must we already be on 4.1.2 to flash this bootloader? I'm running AOKP's JB4 (built on 4.1.1 of course) and have tried flashing 3.41 via both TWRP (zip file in OP) and fastboot (bootloader-grouper-3.41.img from Google). I always have to fastboot back to 3.34 because no matter what it gets caught in a bootloop.


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## heath2805

kbluhm said:


> Must we already be on 4.1.2 to flash this bootloader? I'm running AOKP's JB4 (built on 4.1.1 of course) and have tried flashing 3.41 via both TWRP (zip file in OP) and fastboot (bootloader-grouper-3.41.img from Google). I always have to fastboot back to 3.34 because no matter what it gets caught in a bootloop.


I flashed it on 4.1.1 stock rooted and works great w/ TWRP.

Sent from my ADR6400L using Tapatalk 2


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## BarberAE

kbluhm said:


> Must we already be on 4.1.2 to flash this bootloader? I'm running AOKP's JB4 (built on 4.1.1 of course) and have tried flashing 3.41 via both TWRP (zip file in OP) and fastboot (bootloader-grouper-3.41.img from Google). I always have to fastboot back to 3.34 because no matter what it gets caught in a bootloop.


It is the same for me. There is a thread on xda with several others having the same problem.


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## kbluhm

BarberAE said:


> It is the same for me. There is a thread on xda with several others having the same problem.


Phew, not just me then.


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## dirtyfingers

Works for me. Thanks


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## Formula84

So I had a HW Version - ER3 and bootloader 3.34 I tried the Zip from the OP...First flash after booting back to bootloader it still showed the old version, second flash from recovery worked and I got 3.41 but I too now have the issue of unable to get to recovery... I can't do it from Rom or Bootloader...You can see it try to go to recovery and just has a black screen and reboots back into android. 

I was on Cookies and Cream (4.1.2) Rom with TWRP 2.3.1

So I am trying now to fastboot back to old Bootloader. I was going to try the whole factory image install but I don't want to do all that and find out it does the same thing still

Edit: I am also one of the people that reported very bad performance once the device get low on storage anything under 3GB free and performance gets increasingly worse (Read/Write of NAND)

Edit 2: Flashed the 3.34 bootloader and able to get right into recovery from bootloader or Rom


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## Formula84

BarberAE said:


> Can't get this to work unless I stick with stock unrooted. Harware Varient ER3


I am also ER3 but I do not get bootloop, it just wont go into recovery anymore... had to go back to 3.34


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## BarberAE

Formula84 said:


> I am also ER3 but I do not get bootloop, it just wont go into recovery anymore... had to go back to 3.34


Same here. I am sticking with 3.34 for now I guess. Weird thing is I was able to get into recovery from the bootloader after downgrading to 3.34 without being plugged into to a computer.


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## Formula84

BarberAE said:


> Same here. I am sticking with 3.34 for now I guess. Weird thing is I was able to get into recovery from the bootloader after downgrading to 3.34 without being plugged into to a computer.





Se7enLC;32709655 said:


> I had a mostly-stock Nexus 7 running 4.1.1 - unlocked, rooted, TWRP installed, but no major /system changes. When the update came in, I figured "what the heck, I'll just see if it applies - worst case I lose root and my recovery console, but it's a nexus, it's easy to get those back". I applied the update, and it worked! It applied and rebooted, worked fine - but it did lose root and recovery as I expected.
> 
> So I tried to get recovery back. It won't come back. Here are the ways I tried:
> 
> Hold down VolUp+VolDown+Power to get to fastboot mode. Ran
> 
> 
> Code:
> 
> 
> fastboot boot recovery.img
> 
> (using a number of different copies of both clockwork and TWRP recovery). Each time, the screen went black, google logo came up, but then it booted to AndroidOS
> 
> Tried to do
> 
> 
> Code:
> 
> 
> fastboot flash recovery recovery.img
> 
> The flash seemed to look like it did fine, but when I selected "Boot Recovery", it didn't. It booted Android OS
> 
> I can get into STOCK recovery using the normal method of selecting it from the menu just fine.
> 
> Stock recovery doesn't have ADB running. Fastboot mode doesn't have adb running. Fastboot doesn't have any command for rebooting into recovery apart from the method I mentioned (fastboot boot recovery.img). Booting into AndroidOS reflashes the recovery console with the stock console (I tried to race it running adb reboot recovery, but lost).
> 
> I tore my hair out for hours. Nothing I tried would let me boot into a custom recovery. I eventually backed everything up as best as I could using adb (Since luckily Android OS still worked), and reflashed to stock everything. PROBLEM IS STILL HERE! Then I decide to revert the bootloader from 3.41 to 3.34. SUCCESS. 3.34 booted to recovery without any problems at all.
> 
> Any idea what the heck is going on here? Anybody else seen this? All the threads I've seen with people having problems booting into recovery end with somebody suggesting "Just get app xyz that will reboot into recovery" - but that is NOT an option if A). you cannot get it to boot or
> 
> 
> 
> 
> 
> 
> 
> . you are not rooted/are running stock, because you can't be in AndroidOS and still have the custom recovery flashed UNTIL you are able to get into recovery to actually fix it.
> 
> Here's a video of me trying to flash recovery, since nobody will believe me that it doesn't work. Turn off the audio, the bell noise is obnoxious, sorry.


Found the solution to the the issue (sorta), I too went through all this trouble as you did in your OP.

I did not have to do anything other then straight up flash this version "recovery-clockwork-touch-6.0.1.5.b8147-grouper.img" via fastboot and bam! recovery works. Link - http://forum.xda-developers.com/showpost.php?p=32810167&postcount=228

Problem is with previous versions of 6.0.1.0 (Official) and TWRP 2.3.1

I still prefer TWRP, but hey This is better then the alternative (No recovery at all)

Now we need to figure out what changed between CWM 6.0.1.0 and 6.0.1.5 and get the other guys (TWRP) to fix their shit for us poor saps that seem to be a minority in the Nexus 7 world having this issue.

I would love to know what actually the fix is and why only some have these issues with older versions of CWM and TWRP.


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## BarberAE

Thanks formula84. That worked for me.


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## wigsplittinhatchet

posted this in my thread on this issue but figured i would post here as well. i spoke with Dees_Troy on IRC and made him aware of the issue and he said he will take a look at it tomarrow. hopefully he can figure this issue out. if he does we owe him a HUGE thanks for helping us out as it seems its only a small number of us having this issue.


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