Toshiba Qosmio F15 Series User Manual page 123

The RTC battery may have become completely discharged
while your computer was shipped, resulting in the following
error message during startup:
BAD RTC BATTERY
BAD CHECKSUM (CMOS)
CHECK SYSTEM
The above error message may vary by computer model.
NOTE
The RTC battery does not charge while the computer is turned
off even when the AC adapter is charging the computer.
If the RTC battery is low, the real-time clock and calendar
may display the incorrect time and date, or stop working.
It is seldom necessary to charge the RTC battery because it
NOTE
charges while the computer is on. If the RTC battery is low, the
real-time clock and calendar may display the incorrect time
and date or stop working.
When Hibernation mode is enabled and the RTC battery is
completely discharged, a warning prompts you to reset the
real-time clock.
The computer can be used while the RTC battery is being
charged, although the charging status of the RTC battery
cannot be monitored.
Mobile Computing
Charging the batteries
123