LG G Pro F240K (Korean Model) Unrooting and Software Update

LG 지 프로 KT, 언루팅 & 소프트웨어 업데이트

한글 요약: 루팅이 되었기에 OTA 소프트웨어 업데이트를 할 수 없던 젤리빈 LG G Pro(KT버전)를 아래 Way 3에 소개된 방법으로 킷캣으로 업그레이드 할 수 있었다.

Situation: Trying s/w update (4.4.2 Kitkat) on a rooted LG G Pro (F240K) of 4.1.2 Jellybean

Why: Abnormally slowed response recently and needs of unrooted phone

Problem: LG blocked s/w update on a rooted phone

Way 1.
Trying to unroot with keeping 4.1.2
Failed: Couldn't find the unrooting tool which is related to my previous rooting tool.

Way 2.
Using LG Mobile Support Tool
Failed: The program keeps saying the battery is low even though it's fully charged.

Way 3.
Using LG Flash Tool 2014 with the Jellybean KDZ file for F240K
Succeeded: Hurray!

Preparation: LG Mobile Support Tool (B2CAppSetup.exe), LG Flash Tool 2014 (.zip), KDZ file for F240K (.kdz)

1. Run LGFlashTool2014.exe as an administrator
2. Select Type: CDMA
3. PhoneMode: EMERGENCY
4. Select KDZ file
5. Click [CSE Flash]
6. Click [Start]

Then it will run LG Mobile Support Tool and start firmware update.

I don't know why, but in my case, it stopped at 4% and showed some instructions of rebooting the phone and there was a [Retry] button. Instead of following the sentences I just click the [Retry] button and it proceeded greatly up to 95%, and then the phone was rebooted.

The initial setting steps were begun with the greeting Droid image, but the proceeding bar was 95% still so I was waiting and finally it became 100% without any change on the phone screen. I unplugged the USB cable and checked the s/w version which was changed to Jellybean, of course not rooted.

After 6 times of trials of s/w update from Jellybean to Kitkat, the phone works finely awesome! It responses as a quad-core device. I had to select and install 78 apps manually from my previously installed app list of the Google Play Store but it was a chance for me to organize the unused apps, so no problem.

Big thanks to all xda devs and the uploaders of tools and kdz files. You're super!