Before you buy a new cell phone or new tablet, please try the following procedure to repair your device. First charge your battery, backup your important data if possible and in most cases take out SIM and SD card before factory reset. It is impossible to recover your data after doing a hard reset, so online backup is always important. For all of your data, a backup should be done on an external device, hard drive, raid system or media. With or without insurance, if your cell phone lost, damaged or stolen at least your invaluable data is backed up in a safe place. If you are about to sell your phone and you want to wipe your personal data, or if your phone affected with virus you have to do a hard reset. In some cases, you can delete the forgotten password or lock pattern from your device as well. All information is for devices with stock based ROMs. If you are using rooted device, always back up your EFS folder first, containing your IMEI info, etc.!
LG Optimus F5 hard resetUsing the Optimus LG F5 / LG AS870 hard reset
Hard Reset (Factory Reset) LG P875
1. Turn the power off.
2. Press and hold the following keys at the same time:
Power/Lock Key + Volume Down Key.
3. Release the keys when the FACTORY HARD RESET screen is displayed.
4. Press the Power/Lock Key to continue or the Volume Keys to cancel.
To reset your LG Optimus F5 Andorid Jelly bean or ICS to factory settings and erase all the data on your phone using the menu, select Settings → Back up and reset→ Factory data reset → Reset device→ Delete all.
1. On the Home screen, touch the Menu Key .
2. Touch System settings > Backup & reset > Factory data reset.
NOTE You can touch the checkbox to also erase all contents from your microSD card when the phone is reset.
3. Read the warning and touch Reset phone.
4.Touch Erase everything.
Attention: If a factory reset is performed, all installed application and user data will be erased. Please remember to back up any important data before performing a factory reset.
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.
You can use LG Mobile Support tool to repair your LG cell phone, after download select menu Customer Support > Recovery Phone (AS870)
Go to Support > Mobile Phone Support > Select the Model AS870