IBM ThinkPad 340 Series Hardware Maintenance Manual page 41

Terminal
1
2
3
4
3. If the voltage is less than +10.0 V dc, the battery pack
has been discharged or is defective. Recharge the
battery. If the recharging does not work, go to Step 5
to check the charging circuit.
If the voltage is still less than +10.0 V dc after the
recharging, replace the battery.
4. If the voltage is more than +8.0 V dc, measure the
resistance between battery terminals 3 and 4. The
resistance must be 4 to 30 kilohms.
If the resistance is not correct, replace the battery
pack.
If the resistance is correct, replace the system board.
5. To check the charging circuit, do the following. Plug
in the AC Adapter with the battery pack removed;
then power-on the computer.
6. Measure the charging voltage between terminals 1 (+)
and 4 (−) on the computer.
7. If the voltage is less then +10.0 Vdc, replace the
system board. If the voltage is more than +10.0 Vdc,
the charging circuit is working correctly, replace the
battery pack.
Checking the Backup Battery
1. Power-off the computer and unplug the AC Adapter
from the computer.
2. Remove the backup battery.
3. Measure the voltage of the backup battery. See the
following figure.
4
(
Voltage (V dc) / Signal
340 (NiCd)
+10.0 to +18.0
NC
10 kΩ between ground (−)
ThinkPad 340x (IBM 2610)
1
( )
3
( )
)
340CSE (NiMH)
+10.0 to +16.0
0 Ω+0 ground (−)
Ground (−)
31