IBM ThinkPad 560Z, Hardware Maintenance Manual

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reinstalled battery pack is not charged, go to the next
section.
Checking the Battery Pack:
Battery charging will
not start until the Fuel-Gauge shows that less than 95% of
the total power remains; with this condition the battery
pack will charge to 100% of its capacity. This protects the
battery pack from being overcharged or having a
shortened life.
Do the following:
1. Power off the computer.
2. Remove the battery pack and measure the voltage
between battery terminals 1 (
+
) and 4 (
−
). See the
following figure:
3. If the voltage is less than
+
11.0 V dc, the battery pack
has been discharged. Recharge the battery pack.
Note: In this case, the battery pack is
over-discharged. It takes the at least 2 hours
to recharge the battery pack even if the
indicator does not turn on.
If the voltage is still less than
+
11.0 V dc after
recharging, replace the battery pack.
4. If the voltage is more than
+
11.0 V dc, measure the
resistance between battery pack terminals 3 and 4.
The resistance must be 4 to 30 K ohm.
If the resistance is not correct, replace the battery
pack. If the resistance is correct, replace the system
board.
Checking the Backup Battery
1. Power off the computer and unplug the AC Adapter
from the computer.
2. Turn the computer upside down.
3. Remove the backup battery (see “1010 Backup
Battery” on page 45).
4. Measure the voltage of the backup battery. See the
following figure.
Note: Be careful not to measure the wrong side of
the backup battery.
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