IBM ThinkPad 380Z, Hardware Maintenance Manual

Page: 16 / 104

b. If the voltage is correct, make sure the
connection between the DC/DC card and the
system board is not loose.
c. Replace the DC/DC card.
d. If the problem is not corrected, replace the
system board.
e. If the problem persists, go to “Undetermined
Problems” on page 32.
2. Unplug the AC Adapter cable from the ac power
outlet and wait 5 minutes or longer to allow the
overvoltage protection circuit to be fully discharged
and initialized.
3. Plug the AC Adapter cable into the ac power outlet.
4. Measure the output voltage of the AC Adapter.
5. If the voltage is still not correct, replace the AC
Adapter.
Note: An audible noise from the AC Adapter does not
always indicate a defect.
Battery Checkout:
If the error is due to the battery,
do the following:
1. Turn off the computer.
2. Remove the battery and measure the voltage
between the battery terminals 1 (
+
) and 4 (
−
).
Note: Signal lines not used in these steps are used
for communication between the system and
the battery.
3. If the voltage is less than
+
11.0 V dc, the battery has
been discharged. Recharge the battery.
If the voltage is still less than
+
11.0 V dc after
recharging, replace the battery.
Note: The voltage of the battery could show 0 V
because of the overdischarge protection
Terminal Voltage (V dc) / Signal
1
+
0 to
+
13.5
4 Ground (
−
)
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