Laptop User Manual

circuit. Try to trickle charge the battery by
attaching it to the computer with the AC
adapter.
4. If the voltage is more than +11.0 V dc, measure the
resistance between the battery terminals 3 and 4.
The resistance must be 4 to 30 K ohms.
If the resistance is not correct, replace the battery.
If the resistance is correct, replace the DC/DC card.
Checking Operational Charging
Note
Battery charging will not start unless the Fuel-Gauge
is below 95%. At below 95%, the battery will start
charging to 100% of its capacity. This limitation
protects the battery from overcharging and also
prolongs its life.
To check the operational charging, install a fully
discharged battery or a battery that is less than 50%
charged.
Turn on the computer while it is connected to the AC
Adapter. If the battery status indicator does not turn on,
turn off the computer, remove the battery, and let the
battery return to room temperature. Reinstall the battery,
and turn on the computer (still connected to the AC
Adapter). If the charge indicator still does not turn on,
replace the battery.
Backup Battery Checkout
(Nonrechargeable)
1. Turn off the computer and unplug the AC Adapter
from the computer.
2. Open the Mmoery-slot cover.
3. Remove the backup battery. (Refer to “1010 DIMM
Card and Backup Battery” on page 45 to remove the
battery.)
4. Measure the voltage of the backup battery connector.
ThinkPad 380Z 15