Checkout guide
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 com puter upside down.
3.
Remove the battery pack (see " 1010 Battery pack" on
page 6 4 ).
4.
Remove the backup battery (see "C hecking the battery
pack" on page 4 0 ).
5. M easure the voltage of the backup battery. See the
following figure.
B lue(-)
•
If the voltage is correct, replace the system board.
•
If the voltage is not correct, replace the backup battery.
•
If the backup battery discharges quickly after
replacement, replace the system board.
4 2
ThinkPad R40
W ire
Voltage (V dc)
Red
+2.5 to +3.2
Blue
Ground