Checking Operational Charging; Checking The Battery Pack; Checking The Backup Battery - Lenovo ThinkPad S431 Hardware Maintenance Manual

To check the ac power adapter, do the following:
1. Unplug the ac power adapter cable from the computer.
2. Measure the output voltage at the plug of the ac power adapter cable. See the following illustration:
Note: Output voltage across pin 2 of the ac power adapter might differ from the one you are servicing.
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 operational charging

To check whether the battery pack charges correctly during operation, do the following:
1. Discharge the battery pack until the remaining battery power is less than 50%.
2. Connect the computer to ac power to charge the battery pack. If the battery status icon in the Windows
notification area indicates that the batteries are not charging, disable the built-in battery in the BIOS,
remove the battery pack, and let them return to room temperature.
3. Reinstall the battery pack. If the batteries are still not charging, replace the battery pack.
4. Check the battery status icon again. If the same error still exists, replace the system board. Otherwise,
check the original battery pack. See "Checking the battery pack" on page 29.

Checking the battery pack

This system 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.
To check for detailed battery status information, do the following:
• For the Windows 7 operating system: Open the Power Manager program and click the Battery tab.
• For the Windows 8 operating system:
– Open the Lenovo Experience program and click Power.
– Open the Lenovo Support Center program and click Battery Health.

Checking the backup battery

To check the backup battery, do the following:
1. Disable the built-in battery. See "Disabling the built-in battery" on page 60.
2. Remove the backup battery (see "1070 Backup battery" on page 67).
3. Measure the voltage of the backup battery. See the following figure.
Pin
Voltage (V dc)
1 +20
2 0
3 Ground
.
Chapter 3 General checkout
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