[Android Q&A, Help & Troubleshooting] Teddy Lo:
Hello everyone, today I will show you my way how to unbrick hard-bricked Selecline MW7526L - 871023 S4T7IN with mainboard [BND-RK3126-K86-YH A2.4] for free by without InfinityBox CM2RKT v2.01 or others...

The way I figured out on my own without box cost me 2 days of trying searching online and I was very disappointed because there is almost no support for devices like this, and if you find something you can't download without membership, so I pass hard way to figured out the right way to make a live this device again, but I decided to make it very easy for you guys with all already prepared files to save your time :).

BEFORE WE START - open your device and check if your mainboard is with code [BND-RK3126-K86-YH A2.4] if not don't try it.

See Pictures:

image 1

https://ibb.co/hcn1R21

Image 2

https://ibb.co/184WBmg

So let's Start

1. Download and extract files to your Desktop drivers , flash tool and firmware:

Edit:

Links updated

#Firmware:

Auchan SELECLINE RK312X v5.1.1 Firmware.zip

drive.google.com

#Driver Assistant

Rockchip DriverAssitant_v4.4

MediaFire is a simple to use free service that lets you put all your photos, documents, music, and video in a single place so you can access them anywhere and share them everywhere.

www.mediafire.com

#Flash tool

AndroidTool_Release_v2.35.rar | by heatshiver for Generic Device/Other

Download GApps, Roms, Kernels, Themes, Firmware, and more. Free file hosting for all Android developers.

androidfilehost.com

1.1 Install drivers

Now once you extracted file inside you will find Rockchip_DriverAssitant_v4.4 folder, open it and Run DriverInstall.exe in order to install driver.

There’s no need to connect your Rockchip device during this procedure, a very important thing is if you've previously tried to install the Rockchip USB drivers for any Rockchip devices make sure you click “Uninstall Driver” first and then Re-open DriverInstall.exe and click on “Install Driver”.

See steps in pictures:

image 1

https://ibb.co/wYd6SSJ

image 2

https://ibb.co/ypd9B36

image 3

Click on "Run"

https://ibb.co/qpZXTPg

image 4

Click on "Install Driver"

https://ibb.co/0KsxRTW

Image 5

Click “Install Driver”, and depending on your version of Windows the Security below may show up twice during installation. Just click “Install”.

https://ibb.co/FKQTBm3

Image 6

Once driver is installed click "Okay" and Exit from RK Driver Assistant v4.4

https://ibb.co/2v74MyH

1. 2 Now extract downloaded firmware to Desktop or wherever you want.

For me is easy to create one new folder on Desktop with name MW7526L - 871023 S4T7IN

But you can do how is easy for you :) ...

1.3 Now extract downloaded flash tool and run "AndroidTool.exe" and load all prepared files from Selecline MW7526L - 871023 S4T7IN folder where you extracted files. In my case I extracted to the Desktop so my location is C:\Users\Maksim\Desktop\Selecline MW7526L - 871023 S4T7IN\Flash tool and files\image .And load each one and make sure to check all boxes exept userdata.

See steps in pictures:

image 1

https://ibb.co/Yhy3wc8

Image 2

https://ibb.co/F6fhHMK

Image 3

Check all except the userdata and load parameter file from extracted firmware in my case Selecline MW7526L - 871023 S4T7IN\Flash tool and files folder each img files one by one except the user data and Radial update from Selecline MW7526L - 871023 S4T7IN\Flash tool and files\image folder.

https://ibb.co/Pzq87sw

4. Now press together Vol + / Vol- and plug usb cable and press also Power button for few seconds for device to be detected like Loader inside tool.

Then once is detected press on "Lower Format" and wait to be done. Then again do the same step and now press "Run"and wait for progress to complete full and your device will boot ....

image 1

https://ibb.co/QdNcVsq

image 2

https://ibb.co/5xqSzsv

image 3

https://ibb.co/xDnvTzy

Now once device is booted it will take more than 5 minutes to load so all you need to do is to force your device to boot into Recovery mode, to do that once device is stucked on boot logo just HOLD together Power button and Vol + button and just hold like that and your device will reboot and don't release buttons until you see you are in recovery mode.

You will facing errors like

E: failed to load cache ... it will be fixed after factory reset

E: failed to load rknand ... it will be fixed after factory reset

E: failed to mount /mt/sd ... it means that device can't mount micro sd card because is not existed

Ignore those and just simple with Vol- go to Wipe Cache partition and confirm with one time pressedPower button .

Now once is completed go to Wipe data /Factory reset and confirm with Power button . Once is once is completed go to Reboot system now and confirm with one time pressed Power button .

See Pictures:

image 1

https://ibb.co/MZqm1KJ

image 2

Without sd card

https://ibb.co/D1Hq9rD

image 3

With sd card inside it

https://ibb.co/g4Swmgn

FINAL RESULT

image 1

https://ibb.co/jgkS19C

image 2

https://ibb.co/pn6b0zx

To make it work properly update Google play services and also apps like YouTube, Google, etc...

Device is slow with 512MB of RAM so don't expect to be so fast like devices with 2GB or more ....

FLASH TOOL CAN'T DETECT YOUR DEVICE

Solution:

Short 7-8-9 pin from nandchip with tweezers or some wire carefullyor and plug the usb cable while you shorted those pins from nandchip.

See picture:

image

https://ibb.co/bP4WYWC

Device it will be detected inside flashtool like Found One MASKROM Device and flash as in the instructions above and it should be fine.

That's it 👼:highfive:

Good luck