Sony NAV-U NV-U44 Instruction Manual page 6

Other basic menu operations
To
cancel the setting
confirm the selection/proceed to the next step "Done" or "OK"
About the battery status indication
The battery status can be checked by the indicator in the main menu.
Indicator Status
Adapter connected.
Fully charged.
Not fully charged.
Low battery.
Battery is empty. Charge battery immediately.
Touch
"Cancel"
6