To create a bootable diagnostic medium, do the following:
1. Go to http://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.
To use the diagnostic medium you have created, 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 26,
and check the power sources. If an error code is displayed, go to “Symptom-to-FRU index” on page 34
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 will be launched
5. 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. Remove the battery pack.
3. Connect the ac power adapter.
4. Check that power is supplied when you turn on the computer.
5. Turn off the computer.
6. Disconnect the ac power adapter and install the charged battery pack.
7. Check that the battery pack supplies power when you turn on the computer.
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 operational charging” on page 27
• “Checking the battery pack” on page 27
• “Checking the backup battery” on page 28
Checking the ac power adapter
If you computer fails only when the ac power adapter is used, use the instructions in this topic.
• If the power-on indicator does not turn on, check the power cord of the ac power adapter for correct
continuity and installation.
• If the computer does not charge during operation, go to “Checking operational charging” on page 27.
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:
26 Hardware Maintenance Manual