Checking Operational Charging; Checking The Battery Pack - Lenovo ThinkPad X200 Tablet 7449 Hardware Maintenance Manual

Checking operational charging

To check whether the battery charges properly during operation, use a discharged
battery pack or a battery pack that has less than 50% of the total power remaining
when installed in the computer.
Perform operational charging. If the battery status indicator or icon does not turn
on, remove the battery pack and let it return to room temperature. Reinstall the
battery pack. If the charge indicator or icon still does not turn on, replace the
battery pack.
If the charge indicator still does not turn on, replace the system board. Then
reinstall the battery pack. If it is still not charged, go to the next section.

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 your battery, move your cursor to the Power Meter icon in the icon tray
of the Windows
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
3. If the voltage is less than +11.0 V dc, the battery pack has been discharged.
4. If the voltage is more than +11.0 V dc, measure the resistance between battery
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ThinkPad X200 Tablet Hardware Maintenance Manual
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taskbar and wait for a moment (but do not click), and the
(+) and 7 (-). See the following figure:
7(-)
6(-)
5
3 4
2(+)
1(+)
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.
terminals 5 and 7. 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.
Terminal Voltage (V dc)
1 + 0 to + 12.6
7 Ground (-)