为了解决wechat的video chat 屏幕黑的问题,我的V版VS 980 LG G2 最近不幸被老婆 update成最新的Andriod的5.02了,而这个android 5耗电厉害无比,电池一天都支撑不 住。没有办法,我只有想办法把系统降低到更稳定的4.4.2,it turns out not so simple,中间碰到了各种奇怪的问题, but I get it done finally. Here is the steps: 1. 准备工作: 下载USB driver LG VZW_United_WHQL_v2.11.1.exe 并安装 下载LG flash tool 2014 并un-zip 到电脑 下载 Andiord 4.4.2 的.kdz 文件@ http://forums.androidcentral.com/verizon-lg-g2/522287-anyway-downgrade-verizon-lg-g2-kitkat.html 并放到flash tool 2014 folder 下面 2. 在手机上开通developper debug 模式: Enable Developer mode by: LG G2, G3: Settings > About phone > Software information > Build number, tap it for 7 time After the 7th tap, the Developer options will be unlocked and available. They can usually be found in the main settings menu. You dive into that menu to do things like enable USB debugging (a frequent prerequisite to lots of hacks). To enable USB Debugging, navigate to Settings > Developer Options and enable USB Debugging. 3. 进入phone的upgrade firmware模式(download 模式)和改port #: Turn your LG G2 off. Connect it to the PC using a USB cable; press Volume Up while plugging the device onto PC USB port. 如果你做对了的话,G2屏幕上会出现"upgrade firmware, download mode"几个小字。BTW,我弄了好几次才成功进入这个mode。 On your computer, open Device Manager and from COM section locate the LG entry. Right click on it and choose proprieties. Click on Port Settings tab and select the Advanced button. Change the COM port number to CM41 and close the window. 4.在G2的download模式下(这个一定需要,如何实现见3),run LG flash tool 2014, 具体instruction 见链接: http://forum.xda-developers.com/showthread.php?t=2797190 在flash 100%后,手机会自己重启。我碰到了一个问题:手机在verizon wilress的页 面就进入不了了,不断重复。我是通过不登机reset手机解决的: reset LG G2 without log in: Press and hold the Volume Down button and the Power button. When the LG logo is displayed release the Power button only then immediately press and hold the Power button again. Release both buttons when the Factory data reset screen displays. From the Factory data reset screen, select Yes. 重置手机后就进入了正常页面,看了phone information,已经成功downgrade到4.4.2. Everything working fine now. Wish it is useful.