When your phone is stuck in a boot loop, facing a "Firmware Update" screen, or suffering from severe lag after an OTA update, the LG Flash Tool provides a way to wipe the slate clean. By using a KDZ file—which is the official firmware container for LG—you can rewrite the entire operating system and return the phone to its factory state.

LG Flash Tool remains the go-to software for LG smartphone owners looking to revive their devices from software malfunctions or simply upgrade to a specific firmware version. Specifically, the 2017 iterations and versions compatible with KDZ files are essential for managing devices from that era, such as the LG G6, V20, and earlier models like the G5 and G4.

Once you have your files, power off your LG phone. Hold the Volume Up button while connecting the device to your PC via USB. This should trigger "Download Mode." Launch the LG Flash Tool executable as an administrator. In the tool’s interface, set the Select Type to CDMA (a common workaround for many models) and the PhoneMode to DIAG. Load your KDZ file into the Select KDZ file field.