Unlocking redmi 4 pro bootloader (Unofficial way)

[kentaurest]

For all who are waiting for unlocking permission, you don't need to - if you'd like to root and install twrp.
Warning do not flash xiaomi.eu global or any other unofficial rom this way !

Good news - there is now patched aboot with installation instructions

I bought my redmi 4 pro from geekbuying and it came with preinstalled google play and semi mutlilingual (fake) Miui global 8.0.5.0.0(MBECNDG)
It seems geekbuying has installed a modifyed aboot (android bootloader), if you overflash it with xiaomi stock your device will check the rom for valid signing.
So you probably could flash unofficial rom if you don't flash aboot, but I can't test it anymore :/

btw I did this using linux and I used adb from Flashtool

As I still needed root so I tryed to unlock using fastboot :

First enable developer options by clicking on miui version in about phone menu
Go to Systems & Device > Additional Settings > Developers options
allow oem unlock and usb debugging
connect to the computer and allow access
turn off device
hold vol down and power - device reboots to fastboot
fastboot oem device-info
fastboot oem unlock-go
fastboot oem device-info < again, to check if its unlocked
restart device

Redo the setup and use browser to download supersu
get Recovery Flashable.zip

now download twrp to the computer
and follow the instructions how to install twrp.
Twrp started in chinese use, settings menu is second up from the right and last tab is language.

Flash supersu

 

[fforward72]

I'll try this when I receive my Redmi 4.
Thanks for sharing!

 

[d3s4nn]

It's that simple ?

I remember that my Redmi Note 3 Pro made some trouble with "unofficial" unlocking, when it comes to different ROMs...

Thanks anyway!

 

[Sirocco.ukr.lviv]

who checked this method?

 

[333hronos]

Not working

FAILED (remote: Token verification failed, reboot the device)
finished. total time: 0.016s

 

[jontseng]

Hi just to say this worked fine for me. Had a new Redmi 4 Prime bought from Gearbest. Fake global rom version exactly same as mentioned above. I used vanilla Minimal ADB and Fastboot.

NB when device arrived no setup ie fake ROM had already been installed and configed (presumably to install play store).

Went straight in and tried the instructions above. Worked fine. Fastbook unlock then TWRP then supersu. Dumped Chinese CM13 ROM on and we're all good.

Not sure why works for some and why doesn't. Perhaps the exact version of the global rom? Perhaps the fact hadn't done anything with ROM and dived straight in with the unlock?

Tx for kentaurest for the tip!

J

 

[mulat666]

Did you check if bootloader was locked before? Maybe it was unlocked by Gearbest when flashing ROM?

PS. I'm waiting for delivery and I will check your method

 

[jontseng]

Did you check if bootloader was locked before? Maybe it was unlocked by Gearbest when flashing ROM?

PS. I'm waiting for delivery and I will check your method

Yeah so device-info before unlock was:
(bootloader) Device tampered: false
(bootloader) Device unlocked: false
(bootloader) Device critical unlocked: false
(bootloader) Charger screen enabled: true
(bootloader) Display panel:

Afterwards it was:
(bootloader) Device tampered: false
(bootloader) Device unlocked: true
(bootloader) Device critical unlocked: false
(bootloader) Charger screen enabled: true
(bootloader) Display panel:

Screenshot here: https://photos.google.com/share/AF1QipMnl4IHWqsJ60emRL-bLFsPdzSRN3EQ-LO9aBR3KgdtH8OVBplWE_AKXuQva_05CA?key=T2dOREx6N2w0SE10SmV6NEJuWHlSWEVJaXUwNU1B
J

 

[gicifix]

Tried with my Redmi 4 Pro who came straight stock from china. It worked. Be sure to install good adb and fastboot drivers and be sure to check the correct developers options.

 

[alexeius]

Yeah so device-info before unlock was:
(bootloader) Device tampered: false
(bootloader) Device unlocked: false
(bootloader) Device critical unlocked: false
(bootloader) Charger screen enabled: true
(bootloader) Display panel:

Afterwards it was:
(bootloader) Device tampered: false
(bootloader) Device unlocked: true
(bootloader) Device critical unlocked: false
(bootloader) Charger screen enabled: true
(bootloader) Display panel:

Screenshot here: https://photos.google.com/share/AF1QipMnl4IHWqsJ60emRL-bLFsPdzSRN3EQ-LO9aBR3KgdtH8OVBplWE_AKXuQva_05CA?key=T2dOREx6N2w0SE10SmV6NEJuWHlSWEVJaXUwNU1B
J

One interesting thing is mine device which is unlocked with miflash shows the second line like this
(bootloader) Device critical unlocked: true.

 

[mulat666]

I've just received phone with the same ROM as in first post. Could you please share ADB drivers? With universal I had:

fastboot.exe oem unlock-go
...
FAILED (remote: Token verification failed, reboot the device)
finished. total time: 0.030s

The same issue on Ubuntu 16.04

 

[jontseng]

Yeah mine is still "device critical unlocked: false" even after flashing other ROMS and mucking around.

Not quite sure what the issue is - did some quick google as maybe its some key system stuff still locked or because I didn't officially flash thru edl mode or something?

Not going to worry about it too much as I seem to be able to flash ROMs and stuff just fine (just flashed XPosed framework as well, FYI). Don't plan to go back to MIUI at any point anyhow - not really my cup of tea.

Would be interested if someone can explain more about this though. What am I missing out on?

PS Just for fun I ran the same fastboot device-info on my old redmi 3 (unlocked the official way) and it didn't have the "device critical unlocked" line at all (true or false..)

 

[kentaurest]

It is dangerous, you can install supersu and twrp this way, but don't flash non official roms.
Xiaomi roms should relock the bootloader.
Also don't try to install xposed, it didn't work for me.

After xposed made my phone bootloop I installed unofficial global and ended up with "bricked phone" left only with fastboot or black screen (qualcomm diagnostics interface 9000E) and couldn't turn off the phone.

I made deep flashing cable - usb cable where you can short GND and D+
http://xiaomitips.com/media/2016/08/Deep-FLash-Cable-Architecture-680x318.jpg

Connected phone to the computer (don't short the cables yet), used "fastboot reboot" to restart phone.
Quickly shorted GND and D+ for a few seconds, then windows installed HS-USB QDloader 9008 driver
and I could use Mi Flash to restore the phone, this time to the china developer rom
(fastboot version ends with .tgz) with clean all and locked options.

I was quite happy with fake global, twrp and supersu, pity xposed ruined it.

 

[kentaurest]

FAILED (remote: Token verification failed, reboot the device)
finished. total time: 0.030s[/CODE]

Use deep flashing usb cable to get to EDL (downloader) mode.

 

[mulat666]

@kentaurest I have a cable, would it work with the same fastboot commands?

 

[kentaurest]

@kentaurest I have a cable, would it work with the same fastboot commands?

Use windows and Mi Flash... as I described or use official unlocking method.

 

[jontseng]

Hi Kentaurest tx for this. Forewarned is forearmed I guess.

So I assume it was the fake global ROM you were having trouble with re: Xposed - you hadn't flashed and other ROMs right?

(I have Xposed working on the 25/11 CM13 ROM from the China MIUI forums... But I guess its something of a crapshoot which ROMs do and don't break the device..)

To clarify (for future) - when you say "don't flash unsupported non xiaomi roms" do you mean any third party ROM, or ROMs now built specifically for the redmi 4?

Tx

J

 

[kentaurest]

To clarify (for future) - when you say "don't flash unsupported non xiaomi roms" do you mean any third party ROM, or ROMs now built specifically for the redmi 4?

To my understanding bootloader checks if the system is signed with xiaomi key or not... so all xiaomi stuff will load, but xiaomi.eu unofficial global would not.

Also there is special Xposed for Miui, which I didn't try, last pages in the thread seem to suggest to use v86.2
http://forum.xda-developers.com/xposed/unofficial-xposed-miui-t3367634

 

[Mithrandir107]

It is dangerous, you can install supersu and twrp this way, but don't flash non official roms.
Xiaomi roms should relock the bootloader.
Also don't try to install xposed, it didn't work for me.

After xposed made my phone bootloop I installed unofficial global and ended up with "bricked phone" left only with fastboot or black screen (qualcomm diagnostics interface 9000E) and couldn't turn off the phone.

I made deep flashing cable - usb cable where you can short GND and D+
http://xiaomitips.com/media/2016/08/Deep-FLash-Cable-Architecture-680x318.jpg

Connected phone to the computer (don't short the cables yet), used "fastboot reboot" to restart phone.
Quickly shorted GND and D+ for a few seconds, then windows installed HS-USB QDloader 9008 driver
and I could use Mi Flash to restore the phone, this time to the china developer rom
(fastboot version ends with .tgz) with clean all and locked options.

I was quite happy with fake global, twrp and supersu, pity xposed ruined it.

Some others used this method instead. for 900E problem. https://www.youtube.com/watch?v=j27x5iJSS40, seems to work for th. Just read it from other forums

 

[jontseng]

To my understanding bootloader checks if the system is signed with xiaomi key or not... so all xiaomi stuff will load, but xiaomi.eu unofficial global would not.

Hmmm. Funny the CM13 ROM runs then.

I suspect given kernal sources haven't been released they are just using the official build kernel, hence it passes any checks?