Lenovo 20RK, Руководство по техническому обслуживанию аппаратной части

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To use the diagnostic medium you have created, connect your computer to a thin keyboard first. Then use
the thin keyboard to perform the following operations:
1. Connect the bootable diagnostic medium to the computer.
2. Restart the computer. When the logo screen is displayed, press the prompt to display the Startup
Interrupt Menu window.
Notes:
• If the computer cannot be turned on, go to “Power system checkout” on page 26, and check the
power sources.
• If an error code is displayed, go to “Symptom-to-FRU index” on page 31 for error code descriptions
and troubleshooting hints.
3. Tap F12 and follow the instructions to start the computer from the bootable diagnostic medium.
4. Follow the instructions on the screen to use the diagnostic program.
Power system checkout
To verify a 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 26
• “Checking the built-in battery and operational charging” on page 27
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 or the port replicator is used, replace the
docking station or the port replicator.
• If the computer does not charge during operation, go to “Checking the built-in battery and operational
charging” on page 27.
Note: Noise from the ac power adapter does not always indicate a defect.
Checking the USB-C type ac power adapter
To check the USB-C type ac power adapter, do the following:
1. Connect the computer to a power outlet and turn on the computer.
2. Start Commercial Vantage program, and then click Hardware Settings ➙ Power . The ac power adapter
information is displayed.
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.
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Hardware Maintenance Manual