LG Motion 4G MS770 hard reset
1. Turn off your MetroPCS LG MS770 android phone.2. Press and hold Volume Down buttons until phone vibrates.
3. Keep tapping the HOME and BACK buttons until Green Android ROBOT.
4. Wait for the Setup screen. This may take for 1-3 minutes.

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To reset your LG Motion 4G MS770 hard reset phone to factory settings and erase all the data on your phone, Select Settings → Back up and reset→ Factory data reset → Reset device→ Delete all.
Resetting the phone does not erase any system software updates you have downloaded or any files on your microSD card, such as music or photos. If you reset the phone in this way, you are prompted to re-enter the same information that you did when you first started Android.
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You can use LG Mobile Support tool to repair your LG cell phone, after download select menu Customer Support > Recovery Phone