I have successfully recovered my dead/hard brick moto g4 plus mobile using below process.
To give you background, I have hard bricked my new moto g4 plus mobile. To do that, I have unlocked boot loader which void my warranty, then I have rooted yet and got root access. Till that it was working. After that I have installed custom rom cyanogenmod 14.1 . It was still working for some days. Now As I came from blackberry z10 to moto, I was missing blackberry hub features, so I downloaded BlackBerry android OS(Blackberry Priv) and tried to flash it. that's it, it stopped working. I know it was stupid things to do

. I have given mobile to service center, other few famous mobile repairing shops, but no one was able to do anything.
My mobile was dead for almost 1 month, I tried lots of option, including MI flash tool, QPST(QFIL) etc. but didn't get it thought it. For current options also I was working for couple days, after that I got the solution.
Let start work now.....
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There are two parts for this tutorial,
Part1 - make your device bootable/softbrick/start in recovery mode. This is difficult part and most of us stuck here only. We need to make device from hard brick to soft brick. Should work for all Qualcomm devices(except hardware failure).
Part2 - Flash ROM to your device. This is easy part and there are lots tutorial/information available to flashing ROM into device. It will be dependent on individual devices.
Part1:- -
Make your PC into Test Mode.
Then run “CMD” or “Windows Terminal” as administrator and type:
bcdedit -set loadoptions DISABLE_INTEGRITY_CHECKS
bcdedit -set TESTSIGNING ON
Download QualcommDrv.zip from here , extract to an empty folder, then open the folder according to your Windows type (x64 or x86) and double click dpinst64.exe (if you have 64-bit Windows) to install the Qualcomm driver
now please connect your Qualcomm Mobile to PC or laptop Your phone should now being detected as “Qualcomm HS-USB QDLoader 9008” and the driver version 2.0.8.7 (please check it through Windows’ “Device Manager”). If its not detected, then you can keep mobile connecting to computer and press power button and volume down button.( This is for motorola g4 plus and can be different for your mobile. )
Now you have your mobile connected to computer, now follow the below steps.
Please download zip " blankflash1.zip" from location here extract it your computer and goto extracted folder and click blank-flash.bat
It will start in command prompt and detect device on your computer port(eg. COM5, COM8 etc).
If process completed successful then your mobile will restart into bootloader screen and your hard brick problem has been resolved. after that you can reboot into recovery by pressing power and volume down button again if required. Once you are in recovery mode then you can flash correct stock ROM into your mobile. Refer below Part2 for this.
If above didn't work and you are getting error like below..
Or any other error, then its little tricky to solve this.
Follow the below steps.
1. Keep your mobile connected using USB, obviously.
2. using one hand keep power button and volume down button pressed at same time and using other hand click blank-flash.bat file.
3. It might be possible that blank-flash.bat scritps get finished earlier, in that case, keep clicking .bat file continuously, you don't need to close previous cmd window. For me it took 5-6 run to get script detect/communicate with device. Here idea is that your mobile should get detected when you press power button+volume button while blank-flash.bat file is still executing.
4. keep trying step 3 unless you dont see below logs.
5. once this is complete then you mobile will boot in bootloader/recovery mode, or you can go to recovery mode using volume up/down button.
After this, your mobile would be detected using adb(android driver), and you can execute fastboot commands.
Note: blankflash1.zip file is working for motorola moto g 4 plus, it should work for other mobiles also. If that doesn't work with your mobile then try with blankflash2.zip and blankflash3.zip files. download here
blankflash1.zip -- is for latest mobile above android lollipop,
blankflash2.zip -- for android lollipop.
blankflash3.zip -- for Kitkat devices.
please try with 1,2 and 3 in order.
Step3 is the key for whole process. you may need to try multiple times while blank-flash.bat is running.
Once you reached here, Congratulations, your mobile is saved and back to life. next part flashing stock rom is very easy. I will try to find url for that.
you just need correct ROM for your mobile and steps to flash it.
Part 2 :
Below is url for motorola, you will get idea how to do it for your mobile by going through it.
Alternative, now you can give your mobile to service center or mobile repair shop to flash ROM.
https://forum.xda-developers.com/moto-g4-plus/how-to/moto-g4-plus-xt1643-updated-signed-t3460695
Other link for flashing ROM into any android mobile:
https://forum.xda-developers.com/wiki/Flashing_Guide_-_Android
https://forum.xda-developers.com/showthread.php?t=2131284
https://www.xda-developers.com/how-to-install-custom-rom-android/
Let me know if you have any doubts/questions, I will try to update.
Also let me know if it helps you and you can also Donate

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