User’s Manual6-4
Power and Power-Up Modes
Battery pack
To ensure that the battery pack maintains its maximum capacity, operate the
computer on battery power at least once a month until the battery pack is fully
discharged. Refer to Extending battery life in this chapter for procedures. If the
computer is continuously operated on AC power through an AC adaptor for an
extended period, more than a month, the battery may fail to retain a charge. It
may not function efciently over the expected life of the battery and the Battery
indicator may not indicate a low-battery condition.

Real Time Clock battery

The Real Time Clock (RTC) battery provides power for the internal real time clock
and calendar. It also maintains the system conguration.
If the RTC battery becomes completely discharged, the system loses this data and
the real time clock and calendar stop working.
The computer’s RTC battery is a lithium ion battery and should be replaced
only by your dealer or by a TOSHIBA service representative. The battery can
explode if not properly replaced, used, handled or disposed of. Dispose of the
battery as required by local ordinances or regulations
n You can change the settings of the Real Time Clock by pressing F2 in
POST.
n After conguring the time and date for the Real Time Clock battery, we
recommend that you turn the power status of your computer to “ON”
so that the Real Time Clock battery is charged. Refer to Chapter 9
Troubleshooting, for details.
If the following message is displayed on the LCD:
ERROR 0271: Check date and time settings.
WARNING 0251: System CMOS checksum bad-Default
conguration used.
Press [F1] to resume, [F2] to setup.