Sony Xperia User Manual page 501

Q
Battery level goes down quickly
A
Are you where signal is weak or have been out of service area for a long period?
Calling where signal is weak or being out of service area uses a lot of Battery.
Q
Cannot install applications
A
Applications cannot be installed with only a little free space on handset or SD Card.
To check free space, see "Storage." Applications not supported by handset cannot
be installed.
Q
Cannot unlock screen
A
Power on handset again. If you are unable to power off handset, Press & Hold
and Volume Up Key at the same time for approximately three seconds, and release
your finger after it vibrates three times. Power on handset again. Data that was being
edited is erased after handset is powered on again.
Q
Display is dark
A
If handset becomes high temperature, Display may become dim. This is normal.
Q
Cannot detect device connected via Micro USB Cable or MHL Cable
A
Detach then reattach device, and then establish the connection. Some devices may
not be detected.
In Home Screen,
Connectivity
Q
Charging stops while charging
A
If handset reaches a high temperature, charging may stop temporarily. This is
normal. When temperature lowers, handset automatically restarts charging.
Q
Handset becomes hot during use
A
Handset may become hot depending on usage, such as calling, using browser,
charging, etc. This is normal. Direct contact or indirect contact (put in a pocket, etc.)
between handset and skin for a long time can cause low-temperature burns.
4
(Settings)
Detect USB device
Xperia Connectivity
OK
USB