Lenovo ThinkPad T495, Hardware Maintenance Manual

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To create a bootable diagnostic medium, do the following:
1. Go to
https://www.lenovo.com/diags
.
2. Click Lenovo Bootable Diagnostics .
3. Follow the instructions on the Web site to create a bootable diagnostic medium on a USB device or disc.
To use the diagnostic medium you have created, do one of the following:
• If you have created the bootable diagnostic medium on a USB device, do the following:
1. Attach the USB device to the computer.
2. Turn on the computer. If the computer cannot be turned on, go to “Power system checkout” on page
28, and check the power sources. If an error code is displayed, go to “Symptom-to-FRU index” on
page 36 for error code descriptions and troubleshooting hints.
3. When the ThinkPad logo is displayed, repeatedly press and release the F12 key. When the Boot Menu
window opens, release the F12 key.
4. Use the arrow keys to select USB HDD and then press Enter. The diagnostic program launches.
5. Follow the instructions on the screen to use the diagnostic program.
• If you have created the bootable diagnostic medium using a disc, do the following:
1. Turn on the computer. If the computer cannot be turned on, go to “Power system checkout” on page
28, and check the power sources. If an error code is displayed, go to “Symptom-to-FRU index” on
page 36 for error code descriptions and troubleshooting hints.
2. Insert the disc into the optical drive.
3. Restart the computer.
4. When the ThinkPad logo 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 if a battery or an ac power adapter is functional, 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 29
• “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 or the port replicator is used, replace the
docking station or the port replicator.
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T495 Hardware Maintenance Manual