Checkout Guide; Testing The Computer; Diagnostics Using Pc-Doctor For Dos - Lenovo T420 Maintenance Manual

Checkout guide

Use the following procedures as a guide in identifying and correcting problems with the ThinkPad Notebook.
Note: The diagnostic tests are intended to test only ThinkPad products. The use of non-ThinkPad products,
prototype cards, or modiied options can lead to false indications of errors and invalid system responses.
1. Identify the failing symptoms in as much detail as possible.
2. Verify the symptoms. Try to re-create the failure by running the diagnostic test or by repeating the
operation.

Diagnostics using PC-Doctor for DOS

The ThinkPad Notebook has a test program called PC-Doctor for DOS (hereafter called PC-Doctor.) You can
detect errors by running the diagnostics test included in PC-Doctor.
Note: PC-Doctor for DOS is available at the following Web site:
http://www.lenovo.com/support
To create the PC-Doctor diagnostic CD, follow the instructions on the Web site.
For some possible conigurations of the computer, PC-Doctor might not run correctly. To avoid this problem,
you need to initialize the computer setup by use of the ThinkPad Setup Utility before you run PC-Doctor.
To enter ThinkPad Setup Utility, do as follows:
1. Turn on the computer.
2. When the ThinkPad logo comes up, immediately press F1 to enter the ThinkPad Setup Utility.
Note: If a supervisor password has been set by the customer, ThinkPad Setup Utility menu appears after the
password is entered. You can start the utility by pressing Enter instead of entering the supervisor password;
however, you cannot change the parameters that are protected by the supervisor password.
On the ThinkPad Setup Utility screen, press F9, Enter, F10, and then Enter.
Note: When you initialize the computer coniguration, some devices are disabled, such as the serial port. If
you test one of these devices, you will need to enable it by using Coniguration utility for DOS. The utility is
available on the following Web site:
http://www.lenovo.com/support
PC-Doctor cannot be used to test a device that is in the docking station, even if the computer supports the
docking station. To test a USB device, connect it to the USB connector of the computer.

Testing the computer

Note: The PC-Doctor diagnostic CD does not support any optical drives connected through USB devices or
any others. It supports only the internal optical drive of the ThinkPad Notebook.
To run the test, do as follows:
1. Turn off the computer.
2. Make sure that the internal optical drive that is supported as a startup device is attached to the computer.
3. Turn on the computer. If the computer cannot be powered on, go to "Power system checkout" on
page 35, and check the power sources.
If an error code appears, go to "Symptom-to-FRU index" on page 45.
4. When the ThinkPad logo comes up, immediately press F12 to enter the Boot Menu.
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Chapter 3 General checkout
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