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Phone doesn’t charge
It takes longer than normal to charge, if at all, or phone doesn’t recognize when charger is connected.
Battery is installed incorrectly
The phone may not charge because the battery has been installed incorrectly. This could be the issue if your phone doesn’t charge, and if it doesn’t power on either. Remove the back cover and reinstall the battery. LG G3 Battery Replacement
If the phone has been using the battery for a while, or if the user has used heavy applications on the phone it may cause the battery to heat up. If the user forgets the charging cable plugged in all night it will weaken the battery, especially if it was charged for a full night over multiple times.
To fix this, start by removing the back cover. LG G3 Battery Replacement
Charging port no longer connects and reads the charger. This requires either soldering or replacing the motherboard.
Charger does not work
Buying a new charger cord or charger box will fix this issue.
Display not turning on
The display does not turn on when the power button is pressed.
Battery is not charged
Plug the charger into the phone, and wait about 10 minutes before attempting to power up the device.
Screen is damaged
There may be physical damage to the screen if it has been dropped or scratched without a protective case. If your phone has physical damage to the screen, then you will need to replace the damaged screen. LG G3 Screen Assembly Replacement
Front camera not operational
If you are trying to take a picture or video with the front camera activated, and you only see a black screen.
Camera is not connected correctly
The ribbon cables connecting the camera to the motherboard may not be connected, or have gotten loose after the phone has been dropped. This can be fixed by reconnecting the camera's ribbon cable to the motherboard. Find out how in the Camera Replacement Guide. LG G3 Front Facing Camera Replacement
Camera manufacture error
The camera may not be operational due to a fault in the manufacturing process, or it may possibly be damaged after the phone has been dropped.
Replacing the camera will fix this. LG G3 Front Facing Camera Replacement
Rear camera is not operational
If you are trying to take a picture or video with the rear camera activated, and you only see a black screen.
Camera is not connected correctly
The ribbon cables connecting the camera to the motherboard may not be connected, or have gotten loose after the phone has been dropped. This can be fixed by reconnecting the camera's ribbon cable to the motherboard. Find out how in the Camera Replacement Guide. LG G3 Rear Facing Camera Replacement
Camera manufacture error
The camera may not be operational due to a fault in the manufacturing process, or it may possibly be damaged after the phone has been dropped. Replacing the camera will fix this. LG G3 Rear Facing Camera Replacement
Volume and /or power button does not respond
When pressing the power or volume button, nothing happens as expected.
Sometimes, dust or dirt can soil the sensors and stop the users input from going through. To clean this up use a cotton swab and alcohol to remove the dust from the sensors.
Misaligned sensor pad
Sensor pads can become loose and become misaligned with the button you are trying to press. This requires that you replace the sensor pad.
There may be damage to the panel due to water. The volume/power panel is a very easy and quick fix with the right replacement parts.
Phone Shuts Down Automatically
Some users have reported that their smartphone automatically shuts down
The software may be malfunctioning. A factory reset is a quick and easy fix to this problem.
Battery is Faulty
The battery may be loose or defective. The simplest option is to replace the battery. LG G3 Battery Replacement
Phone Gets too Warm
This device is known to get too warm and overheat
High Power for Extended Periods of Time
This usually occurs because the background applications running for long periods of time will run the device on high power for too long. A simple fix- cut the background applications when not in use.
To do so, go into Settings – General – Applications and then choose the app and disable auto sync.
High Resolution and Brightness
The LG G3 automatically reduces the brightness if the screen gets too hot, but it may be a good idea to always have the screen brightness at a lower setting.
Phone Case Covers
If the device has a protective case or cover for your LG G3, a potentially simple solution is to remove the case when the user will be doing something that may cause the phone to get warm, such as playing high-intensity games.
Interface Slows Down
Issues with lag while navigating around interfaces, getting into and out of applications, the recent apps menu, and a general lag with touch response.
Animation Slowing Phone Down
The Windows Animation may be running too high. To fix this you need to access Developer options to able to change some of things required.
To do so, go to Settings – About Phone – Software Information, and tap on the Build Number seven times. Going back to the main settings menu, Developer options should appear. Now, reduce or completely turn off Windows animation scale, transition animation scale, and Animator duration scale.
Screen Sensitivity Too High
The touch response on the phone may be too high, causing the screen to respond "too much" and create lag.
To fix the touch responsiveness of the screen, go into Settings – Accessibility – touch and hold delay and adjust it there.
High Temperature Property and Thermal Daemon Mitigation
This more complicated solution requires access to a Hidden Menu, which can be done by dialing 3845# with extension *855# for international, *851 for T-mobile, *850 for AT&T. Sprint users can dial 5689#*990# and Verizon users ##228378.
Next, look for High Temperature Property OFF and turn it on. Power off the device for 10 seconds. Then power it on and wait 30 seconds before unlocking it. Repeat the steps above to get to the menu once again, then go to Thermal Daemon Mitigation OFF and turn it on.