Forcibly Powering Off - Sony Xperia1 IV User Manual

fingerprint may be difficult or authentication performance may degrade. Washing/wiping hands,
using different finger, etc. may improve capability.
- Wrinkled after taking a bath, etc.
- Wet with water, sweat, etc.
- Dried
- Covered with grease (e.g. hand cream)
- Dirty with mud or grease
- Rough or injured (cut, inflammation, etc.)
- Abraded and faded
- The shape of fingerprint has changed due to weight loss or weight gain
- The surface condition of finger is extremely different from when you registered fingerprint
Personal authentication and identification are not completely guaranteed by fingerprint
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authentication technology. Note that SoftBank Corp. is not liable for any damage incurred due to
misuse by a third party or due to handset being unable to be used.
Precautions on Fingerprint Sensor
- Do not hit or apply strong impact. This may cause a malfunction or damage. Also, do
not scratch the surface or poke it with a sharp object such as a ballpoint pen or pin tip.
- Do not attach stickers or do not daub with ink, etc.
- If dirt such as dust or sebum is attached to Fingerprint Sensor, reading fingerprints
may be difficult or the authentication performance may be degraded. Occasionally clean
the surface of Fingerprint Sensor.
- If the time of touching is too short or too long, authentication may fail. Touch the center
of Fingerprint Sensor straight with the vortex of your fingerprint.
- Activating Fingerprint Sensor may fail if a finger is placed on it before starting
registration or authentication. Release your finger once and try again.

Forcibly Powering Off

If Display stops responding or handset cannot be powered off, Long Press both Power Key and
Volume Up Key at the same time for at least 10 seconds. After handset vibrates three times in a
row, release Keys and handset powers off.
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Safety Precautions