Lenovo T420i manual If an error code appears, go to “Symptom-to-FRU index” on page

3.Turn on the computer. If the computer cannot be powered on, go to “Power system checkout” on page 34, and check the power sources.

If an error code appears, go to “Symptom-to-FRU index” on page 43.

4.When the ThinkPad logo comes up, immediately press F12 to enter the Boot Menu.

5.Insert the PC-Doctor CD into the optical drive.

6.Press cursor keys to select ATAPI CDx (x: 0, 1, ...) and then press Enter.

7.Follow the instructions on the screen.

8.The main panel of PC-Doctor appears.

9.Select Diagnostics with the arrow keys, and press Enter.

Note: You can select an item not only with the arrow keys, but also with the TrackPoint® pointer. Instead of pressing Enter, click the left button.

A pull-down menu appears. (Its exact form depends on the model.)

Note: PC-Doctor menu does not mean the formal support device list. Some unsupported device names may appear in the PC-Doctor menu.

Diagnostics

Interactive Tests Hardware Info Utility Quit F1=Help

Run Normal Test

Run Quick Test

CPU/Coprocessor

System Memory

Systemboard

Video Adapter

Fixed Disks

Diskette Drives

Other Devices

Communication

Wireless LAN

PC-DOCTOR 2.0 Copyright 2008 PC-Doctor, Inc. All Rights Reserved.

Use the cursor keys and ESC to move in menus. Press ENTER to select.

The options on the test menu are as follows:

Diagnostics		Interactive Tests
•	Run Normal Test	•	Keyboard
•	Run Quick Test	•	Video
•	CPU/Coprocessor	•	Internal Speaker
•	System Memory	•	Mouse
•	Systemboard	•	Diskette
•	Video Adapter	•	System Load
•	Fixed Disks	•	Optical Drive Test
•	Diskette Drives	• Intel WLAN Radio Test
•	Other Devices
•	Communication
•	Wireless LAN

Notes:

• In the Keyboard test in Interactive Tests, the Fn key should be held down for at least 2 seconds; otherwise, it cannot be sensed.

• Video Adapter test supports only the LCD display on the ThinkPad Notebook. If you have an external monitor attached to your computer, detach it before running PC-Doctor for DOS.

• To test Digital Signature Chip, the security chip must be set to Active.

10. Run the applicable function test.

30ThinkPad T420 and T420i Hardware Maintenance Manual