IBM ThinkPad TransNote, Hardware Maintenance Manual

Page: 33 / 150

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“Checking the battery pack” on page 30
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“Checking the backup battery” on page 31
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“Checking the sub-battery” on page 31
Checking the ac adapter
You are here because the computer fails only when the ac
adapter is used:
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If the power problem occurs only when the port
replicator is used, replace the port replicator.
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If the power-on indicator does not turn on, check the
power cord of the ac adapter for correct continuity and
installation.
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If the computer does not charge during operation, go to
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Checking operational charging.
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1. Unplug the ac adapter cable from the computer.
2. Measure the output voltage at the plug of the ac
adapter cable. See the following figure:
Pin Voltage (V dc)
1 +15.5 to +17.0
2 Ground
If the voltage is not correct, replace the ac adapter.
If the voltage is acceptable, do the following:
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Replace the system board.
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If the problem persists, go to “Product overview” on
page 35.
Note: Noise from the ac adapter does not always indicate
a defect.
Checking operational charging
To check operational charging, use a discharged battery
pack or a battery pack that has less than 50% of the total
power remaining when installed in the computer.
Perform operational charging. If the battery status indicator
or icon does not turn on, remove the battery pack and let it
return to room temperature. Reinstall the battery pack. If
the charge indicator or icon still does not turn on, replace
the battery pack.
If the charge indicator still does not turn on, replace the
system board. Then reinstall the battery pack. If the
reinstalled battery pack has not been charged, go to the
next section.
Checkout guide
General descriptions
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