Sony PCG-R505JL - Manual (Page 29)

Connecting a Power Source
29
The battery indicator on the front of the notebook indicates the status of the
battery pack.
To remove the battery pack
You can remove the battery pack while your notebook is on or off. However, if
you remove the battery pack while your notebook is on, make sure the notebook
is connected to the AC adapter.
1 Close the cover of the notebook.
2 Slide the lock lever to the UNLOCK position.
Battery Indicator
Battery Indicator
Status
Meaning
On The notebook is using battery power.
Single blink The battery is running out of power.
Double blink The battery is charging.
Off The notebook is using AC power.
✍
Both the battery and power indicators blink when the battery is running out of power.
Battery Indicator
Battery Pack
(supplied)