Toshiba Equium 5160D Series Preliminary Maintenance Manual page 34

Real-Time Clock Battery
A coin-cell style battery, installed in a socket on the system board, provides power for the
real-time clock and CMOS RAM.
The battery has an estimated life expectancy of three years. When the battery starts to
weaken, it loses voltage. When the voltage drops below a certain level, the system settings
stored in CMOS RAM (for example, the date and time) may be wrong. If the battery fails,
replace it with an equivalent battery.
Figure 1-19 Real-Time Clock Battery
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