Power System Checkout; Checking The Ac Power Adapter; Checking The Built-In Battery And Operational Charging - Lenovo X380 Yoga Hardware Maintenance Manual

3. Restart the computer.
4. When the logo screen is displayed, repeatedly press and release the F12 key. When the Boot Menu
window opens, release the F12 key.
5. Use the arrow keys to select ATAPI CDx (x: 0, 1, ...) and then press Enter. The diagnostic program
launches.
6. Follow the instructions on the screen to use the diagnostic program.

Power system checkout

To verify a power symptom, do the following:
1. Turn off the computer.
2. Connect the ac power adapter.
3. Turn on the computer. If the computer can be turned on, it means that either the battery or the ac power
adapter is functional.
4. Insert a straightened paper clip into the emergency-reset hole to reset the computer. If the computer is
still powered on, it means that the ac power adapter is functional.
5. Turn off the computer.
6. Disconnect the ac power adapter and turn on the computer. If the computer can be turned on, it means
that the battery is functional.
If you suspect a power problem, see the appropriate one of the following power supply checkouts:
• "Checking the ac power adapter" on page 28
• "Checking the built-in battery and operational charging" on page 28
• "Checking the coin-cell battery" on page 29

Checking the ac power adapter

You are here because the computer fails only when the ac power adapter is used.
• If the power problem occurs only when the docking station is used, replace the docking station.
• If the system status indicator does not blink three times when an ac power source is connected, check the
power cord of the ac power adapter for correct continuity and installation.
Ensure that you use the USB-C type ac power adapter that is shipped with the computer to provide enough
power to the computer. Otherwise, a message will be displayed, prompting you that the computer will not be
charged or will be charged slowly.
Note: Noise from the ac power adapter does not always indicate a defect.
To check the ac power adapter, do the following:
1. Connect the computer to a power outlet and turn on the computer.
2. Start Lenovo Companion program or Lenovo Vantage, and then click Hardware Settings ➙ Power. The
ac power adapter information is displayed.
If the ac power adapter is working but the computer does not charge during operation, go to "Checking the
built-in battery and operational charging" on page 28.

Checking the built-in battery 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.
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X380 Yoga Hardware Maintenance Manual