[LeEco Le 2 Questions & Answers] delltech1:
Hello,

i have had couple issues so here are my findings, most of them are already nicely described in many topics.

Bricked phone?

For me worked QFIL version 2.0.0.5, using the installer, by the "portable version" errors can be generated:

A nice video tutorial how to use QFIL and restore the image, QFIL and QUALCOMM driver included:

https://www.techpoison.in/2017/12/how-to-flash-letv-le-2-x526-stock.html

To enter the "flash" mode: Press and hold at the same time VOLUME UP, DOWN, POWER for like 10 seconds until you see that the device manager recognized new "hardware". For a detailed tutorial plase follow the video tutorial in the above link.

Should you have problems during the flash process, disconnects and so on, try to use USB 2.0 port.

Version 13s will be restored, please download thee X526 restore image from the Unbrick section or the Indian sparse image from the link above.

Baseband issues after restore / general baseband issues:

After restore "unknown baseband"? Just reset the factory settings on the 13s and let it reboot couple times, it will reboot automatically each 2-3 minutes - let it reboot after the restore 3-4 times. Afterwards copy the stock 21s to internal storage and rename it to update.zip, go to settings,system update and select local update, it should reboot automatically. Its possible that you will get an error message after the 1st reboot - APK not found. Reboot it to OS and delete the update.zip from the internal storage, maybe its not necessary to delete it, but i did it and copied it back, selected local update and voila system updated to 21s, my baseband was back and sims were "fully" functional, 4g/LTE didnt work - baseband was MPSS.TA.2.1.C7-68083.

"I tried to reflash back the stock version using TWRP, stock recovery and also the chinesse TWRP - didnt work at all. "

4g/LTE issues, only 3g works (tested in EUROPE)?

I have flashed all of the modems, bootloaders, different ROMs but it didnt help at all. So i rebooted the phone to fastboot and using the ADB minimal from the CMD i erased both modems, please be sure you have the package of your phone with both IMEIs, in some cases its not necesssary. WCDMA 3G worked fine, i had only issues with 4g/LTE.

IMEI TOOL + drivers link:

https://xdaforums.com/le-2/development/tools-unbrick-thread-leeco-le-2-x52x-t3634609

Imei restore on EUI and other ROMs:

https://www.gizmochina.com/2017/02/17/leeco-letv-imei-repair-qualcomm-models/

Commands to erase the modems: fastboot erase modemst1 and modemst2. I did it on 21s and reflashed the phone using QFIL back to 13s and both sims were already fully functional and 4g/LTE too.

If you do not see any IMEI use the Qualcom Imei Restore application - unbrick section, baseband was back, but i just had to restore the IMEIs, but i saw it only on MIUI 10 8.8.9 global - on MIUI enable the diag port using MINIMAL ADB from the commandline:

MIUI is prerooted, so there shouldnt be issues with root privileges.

Commandline - minimal adb:

adb shell

su

setprop sys.usb.config diag,adb

and run the IMEI restore tool.

In device manager you should see the qualcomm diag port - if you need the qualcomm driver please see the unbrick section.

Before i also tried to type in the dialer *#*#4636#*#* and tried to change the network manually, didnt help at all, tried like 3 sim cards from various operators here supporting 4g with a good coverage.

My phone is fully functional now and 4g/LTE works perfectly.

During all my tests, flashing and so on, if you have issues with a bootloop /custom rom/ and you have flashed already different modems = for me worked the 21s bootloader + modem, fixed most of the bootloops.

Link 21s bootloader + modem:

https://drive.google.com/file/d/0B_RkWxhSoWNLWmJJYmFxTGxlMHM/view

Sorry for my bad english, i am not a native speaker :) All the links are not mine.