[LeEco Le Pro3 Guides, News, & Discussion] hondajohn88:
Hi everyone, I finally got a little time to put together a guide to flashing stuff on the LeEco Le Pro 3 X727.

This phone comes with an unlockable bootloader out of the box, but we found some ways to get around that.

This guide will help anyone with a new X727 unlock the bootloader, install TWRP and root it.

First, I'd like to give huge props to [MENTION=2096805]dr4stic[/MENTION] for his excellent work on making it easier to unlock the phone, and for helping me get back to the US ROM after installing the Chinese rom.

On to the flashing...

If you want to take the long way around, this was the first method used for unlocking the bootloader:

First method is using the stock Chinese ROM & renaming it update.zip, place it in the root directory then use the Update app (or in settings) to select that update, then let it do its thing. It takes a while to boot back up so be patient.

Stock Chinese ROM: https://www.androidfilehost.com/?fid=529152257862681546

Once the Chinese ROM is installed and booted up, enable Developer Options, make sure OEM Unlocking is turned on, then enable USB Debugging.

For these next steps, I'm quoting [MENTION=2096805]dr4stic[/MENTION]:

Have ADB/Fasboot tools on your computer (I am not helping you here, it you're lucky, maybe your friends will help)

Make sure you have enabled the developer tools, turned on USB debugging, and authorized your computer on your device (again, I'm not helping with that)

Make sure adb can see your device when you run "adb devices"

Run "adb reboot bootloader"

Run "fastboot devices" to make sure you see your device

Run "fastboot oem unlock-go" to unlock your device temporarily

Run "fastboot oem device-info" to verify unlock status

Your bootloader is now permanently unlocked (well, until you re-lock it on purpose).

The second, and much shorter method, is outlined in [MENTION=2096805]dr4stic[/MENTION]'s thread here: http://xdaforums.com/le-pro3/development/x727-model-persistent-bootloader-unlock-t3500388

Once your bootloader is unlocked, you'll want to install TWRP.

Here are a couple options for TWRP:

https://www.androidfilehost.com/?fid=529152257862668751 (Chinese version)

https://www.androidfilehost.com/?fid=385035244224398544 (GrossoShop version)

Download either of those (or both if you want to try both), extract them and place the .img file(s) into the folder your ADB & Fastboot files are. To make the flashing easier, rename the twrp files to twrp.img. If you still have your command prompt window open, great! If not, open one again.

Now:

Run "fastboot flash recovery twrp.img" (or whatever the twrp image filename is on your computer) to flash TWRP.

When flashing is complete, reboot into TWRP by pressing and holding Power Button and Volume Up Button at the same time and holding until you see the TWRP splash screen.

If TWRP boots up in Chinese, tap the big button on the lower right to open the language settings and choose the language you can understand.

Alright, now you have an unlocked bootloader and custom recovery installed. Your world has opened up a little bit more :)

The main problem with installing the stock Chinese ROM is that it does not have Google Play and there is no band 12 support (at least for T-Mobile), but at least bands 2 & 4 still work.

It's easy enough to find methods to get that installed, but I tried the GrossoShop ROM which is a very good ROM, but if you must have band 12, you'll need to read down a little farther.

Link to GrossoShop ROM: https://www.androidfilehost.com/?fid=529152257862686304

Okay, if you chose to use the long route and installed the Chinese ROM, you can still get back to the full US version, complete with all LTE bands. dr4stic is responsible for this gem, and was my way back to US ROMdom.

To go from Chinese or Custom ROM back to Stock US version:

The file is located in his Android File Host space here: https://www.androidfilehost.com/?fid=601275311581036717

It's a little tricky to install, so follow these steps:

1. Enter TWRP and from Advanced Wipe, wipe Dalvick/ART Cache, Cache, System and Data (Leave Internal Storage untouched if that's where you copied the new ROM zip).

2. Install CN5.8.018s-to-US5.8.019s.zip

3. DO NOT REBOOT DIRECTLY AFTER FLASHING (Phone just vibrates forever if you reboot directly after flashing)

4. Go back to TWRP Home, then tap Reboot, then tap System.

The phone should reboot after that, and it might take a while. Then follow the setup process as you normally would and it should go through the Google setup as well.

To install root, I use SuperSU. Sometimes it's kinda hard to find the most up to date version, so I'll post the latest one that I have: https://www.androidfilehost.com/?fid=457095661767120474

There's probably a newer version already, but I haven't looked.

Simply download and flash that file in TWRP, reboot and you're rooted. Easy peasy.

To flash only the US modem to restore band 12 on any ROM:

Download: https://www.androidfilehost.com/?fid=601300970940399635

Extract the zip file and place it in your adb & fastboot folder.

From your abd & fastboot files folder (with the modem image in there too) open a command prompt and run

fastboot flash modem modem-5.8.019s.img

Then reboot your phone.

Keep this file handy because you'll need it every time you flash a ROM that doesn't have a US modem.

With the methods listed above, you should now be able to take a new LeEco Le Pro 3 X727 and unlock the bootloader, install TWRP, flash whatever ROMs you want, and restore US modem.

Again, big big thanks to [MENTION=2096805]dr4stic[/MENTION] to getting us to this point for the easy unlock option :) AND big thanks to all of you folks here in the forums for all of you suggestions, efforts and enthusiasm!

I imagine there will be some refinements and/or corrections to this guide as questions and suggestions come up, so please, if you see something in here that is wrong or unclear, please let me know.