Hi Into this guide we are going to talking about lg g4. i will be show you here ho to firmware restore in case you brick it and if you want to unroot your lg g4. lets go do this.first think you need to do on you lg g4 go into setting . general . about phone. you need to find out what your device is so go into software and know your software version. this is you key and identify you phone. Reason we need all of this information to find the right kdz file for our specific Lg G4. Also you have to know about model number in my case it is Lg H815. And that is my Lg G4 Model number.
Pre Requirements To Flash LG G4 :-
Download Lg G4 drivers and install it.
The next thing to do find out the kdz for your Lg g4. so its easy go here and write down your imei. i recommend you to place your model number in search bar look for yoy firmware and download it.
Download LG_Flash_Tool_2014.zip – 3.1 Mb
Extract the LG_Flash_Tool_2014.zip Now click on LG_Flash_Tool_2014.exe. go ahead and open it up. now we have to our lg g4 in download mode first. to do so power down your device..wait for your device completely power off. then hold the volume keep holding it and plug in your device to computer. when your device show the usb logo you are in download mode.
now on lg flash tool select the kdz file.
Now the next is the tricky part if you want to save your app data and more things then select normal flash. And the CSE Flash will wipe your device all data so make you choice.
on next screen click on start button
and wait on next screen just hit the ok .
make sure do not unplug the cable and do not touch any think. lets this procedure go and it may take up to 10 minutes. once its done it should reboot you device automatically. and when you Lg G4 turn on it like a brand new.