Checking The Built-In Batteries And Operational Charging; Checking The Coin-Cell Battery - Lenovo ThinkPad T470s Hardware Maintenance Manual

3. If the voltage is not correct, replace the ac power adapter.
4. If the voltage is acceptable, replace the system board.
Note: Noise from the ac power adapter does not always indicate a defect.

Checking the built-in batteries and operational charging

This computer supports only batteries specially designed for this specific system and manufactured by
Lenovo or an authorized builder. The system does not support unauthorized batteries or batteries designed
for other systems. If an unauthorized battery or a battery designed for another systems is installed, the
system will not charge.
Attention: Lenovo has no responsibility for the performance or safety of unauthorized batteries, and
provides no warranties for failures or damage arising out of their use.
Move your pointer to the battery-status icon in the Windows notification area to check the battery status.
The battery-status icon displays the percentage of battery power remaining and how long you can use
your computer before you must charge the battery.
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. Connect the computer to ac power to charge the battery. If the battery status icon in the Windows
notification area indicates that the battery is not charging, remove the battery and let it return to room
temperature.
Note: The built-in batteries are NOT customer replaceable. Contact a qualified Lenovo technician to
replace the built-in batteries.
3. Reinstall the battery. If the battery is still not charging, replace the battery pack.
4. Check the battery status icon 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 built-in battery. See "Disabling the built-in batteries" on page 64.
2. Remove the coin-cell battery. See "1070 Built-in batteries" on page 76.
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.
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T470s Hardware Maintenance Manual
Wire
Voltage (V dc)
Red +2.5 to +3.2
Black Ground