LG G6 Guia Del Usuario página 31

Scan only one finger for each registration. Scanning more than one
finger may affect fingerprint registration and recognition.
The device may generate static electricity if the surrounding air is
dry. If the surrounding air is dry, avoid scanning fingerprints, or touch
a metallic object such as coin or key before scanning fingerprints to
remove static electricity.
Registering fingerprints
You can register and save your fingerprint on the device to use fingerprint
identification.
1
Tap Settings General Fingerprints & security Fingerprints.
A lock screen must be set in order to be able to use this feature.
If the screen lock is not active, configure the lock screen by following the
on-screen instructions. See
2
Locate the Power/Lock key on the back of the device and gently put
your finger on it to register the fingerprint.
Gently press the Power/Lock key so that the sensor can recognise your
fingerprint. If you press the Power/Lock key with an excessive force, the
screen lock function may start or the screen may be turned off.
Ensure that your fingertip covers the entire surface of the sensor of the
Power/Lock key.
Custom-designed Features
Setting a screen lock for details.
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