Checking the battery pack
Battery charging does not start until the Power Meter
shows that less than 95% of the total power remains;
under this condition the battery pack can charge to 100%
of its capacity. This protects the battery pack from being
overcharged or from having a shortened life.
To check the status of your battery, move your cursor to
the Power Meter icon in the icon tray of the Windows
taskbar and wait for a moment (but do not click), and the
percentage of battery power remaining is displayed. To get
detailed information about the battery, double-click the
Power Meter icon.
Note: If the battery pack becomes hot, it may not be able
to charge. Remove it from the computer and leave it
at room temperature for a while. After it cools down,
reinstall and recharge it.
To check the battery pack, do the following:
1. Power off the computer.
2. Remove the battery pack and measure the voltage
between battery terminals 1 (+) and 5 (−). See the
following figure:
5(-) 4
3
2
1(+)
Terminal
Voltage (V dc)
1
+ 0 to + 12.6
5
Ground (−)
3. If the voltage is less than +11.0 V dc, the battery pack
has been discharged.
Note: Recharging will take at least 3 hours, even if the
indicator does not turn on.
If the voltage is still less than +11.0 V dc after
recharging, replace the battery.
4. If the voltage is more than +11.0 V dc, measure the
resistance between battery terminals 4 and 5. The
resistance must be 4 to 30 K
.
If the resistance is not correct, replace the battery
pack. If the resistance is correct, replace the system
board.
Checking the backup battery
Do the following:
1. Power off the computer, and unplug the ac adapter
from it.
2. Turn the computer upside down.
Checkout guide
General descriptions
37
Summary of Contents for ThinkPad A21m
Page 4: ...iv ThinkPad A20m p A21m p A22m p...
Page 28: ...Laser compliance statement 22 ThinkPad A20m p A21m p A22m p...
Page 76: ...Removing and replacing a FRU 70 ThinkPad A20m p A21m p A22m p...
Page 78: ...continued Removing and replacing a FRU 72 ThinkPad A20m p A21m p A22m p...
Page 108: ...continued Removing and replacing a FRU 102 ThinkPad A20m p A21m p A22m p...
Page 157: ...Notices ThinkPad A20m p A21m p and A22m p 151...
Page 158: ...Part Number 23P0896 1P P N 23P0896...
