Checking The Operational Charging; Checking The Coin-Cell Battery; Checking The Ac Power Adapter - Lenovo ThinkPad X1 Hardware Maintenance Manual

4. Connect the built-in battery and ac power adapter, and then press the power button.
• If the tablet can be turned on, disconnect the ac power adapter from the tablet. If the tablet turns off,
it means that the built-in battery fails.
• If the tablet cannot be turned on, replace the built-in battery with another one. If the tablet can be
turned on with the new battery installed, it means that the original battery fails.

Checking the operational charging

To check whether the battery charges properly during operation, do the following:
1. Discharge the battery until the remained battery power is less than 50%.
2. Perform operational charging. Tap or click the battery status icon in the Windows notification area to
display detailed battery information. If it indicates that the battery is not charging, replace the battery.
3. Check the battery status again. If the same error still exists, replace the system board.

Checking the coin-cell battery

To check the coin-cell battery, do the following:
1. Disable the internal battery pack. See "Disabling the built-in battery" on page 50.
2. Remove the coin-cell battery. See "1030 Coin-cell battery" on page 58.
3. Measure the voltage of the coin-cell battery. See the following illustration.
• If the voltage is correct, replace the system board.
• If the voltage is not correct, replace the coin-cell battery.
• If the coin-cell battery discharges quickly after replacement, replace the system board.

Checking the ac power adapter

This tablet supports only the Lenovo USB-C 45W AC Adapter. When the adapter is connected to the tablet,
the output voltage at the adapter plug rises from 0 V (when not connected) to 5 V. Then the power delivery
communication starts. The ac power adapter outputs 20 V according to the tablet output voltage request.
When you use the ac power adapter to charge the tablet but no power is charged, see the instructions in this
topic to check the ac power adapter.
Note: Noise from the ac power adapter does not always indicate a defect.
To check the ac power adapter when the tablet does not charge, do the following:
1. Disconnect the ac power adapter from the tablet.
2. Connect a new ac power adapter to the tablet. For information about which ac power adapter to order,
go to http://www.lenovo.com/serviceparts-lookup.
3. If the tablet charges, replace the ac power adapter.
Wire
Voltage (V dc)
Red +2.5 to +3.2
Black Ground
.
Chapter 3 General checkout
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