IBM A30P, A31, A31P TROUBLE

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ThinkPad Service and Troubleshooting Guide

A30 Series

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ThinkPad Service and Troubleshooting Guide

A30 Series

Note

Before using this information and the product it supports, be sure to read the general information under “Appendix A. Important safety instructions” on page 37 and “Appendix B. Product warranties and notices” on page 43 .

DANGER

v To avoid electric shock hazard, connect and disconnect cables appropriately when installing, moving or opening

the covers of this product or attached devices. Use the power cord with a properly grounded outlet.

v Do not leave the base of your computer in contact with your lap or any part of your body for an extended

period when the computer is functioning or when the battery is charging. Your computer dissipates some heat during normal operation. This heat is a function of the level of system activity and battery charge level. Extended contact with your body, even through clothing, could cause discomfort or, eventually, a skin burn.

v To reduce the risk of electric shock, do not use your computer in or near water. v To avoid electric shock, do not use your computer with the telephone cable connection during an electrical

storm. Do not connect the cable to or disconnect it from the telephone outlet on the wall during an electrical storm.

v Store packing materials safely out of the reach of children to prevent the risk of suffocation from plastic bags. v The battery pack contains a small amount of harmful substances. There is danger of an explosion if the battery

pack is incorrectly replaced, exposed to fire or water, short-circuited or disassembled. Keep the battery pack away from children and do not put it in trash that is disposed of in landfills.

v To reduce the risk of fire, use only No. 26 AWG or thicker telephone cable. v The fluorescent lamp in the LCD contains mercury. Do not put it in trash that is disposed of in landfills. Rough

handling or dropping the computer can cause the LCD to break and the internal fluid to get into your eyes or on your hands. Immediately wash the affected areas with water. If any symptoms are present after washing, seek medical care.

v Do not open the optical storage drive unit, as this might result in hazardous radiation exposure. v Avoid direct eye exposure with the laser beam contained in some drives.

First Edition (August 2001) Second Edition (August 2001)

The following paragraph does not apply to the United Kingdom or any country where such provisions are inconsistent with local law:

INTERNATIONAL BUSINESS MACHINES CORPORATION PROVIDES THIS PUBLICATION ″AS IS″ WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESS OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF NON-INFRINGEMENT, MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. Some states do not allow disclaimer of express or implied warranties in certain transactions, therefore, this statement may not apply to you.

This information could include technical inaccuracies or typographical errors. Changes are periodically made to the information herein; these changes will be incorporated in new editions of the publication. IBM may make improvements and/or changes in the product(s) and/or the program(s) described in this publication at any time without notice.

IBM may use or distribute any of the information you supply in any way it believes appropriate without incurring any obligation to you.

US Government Users Restricted Rights – Use, duplication or disclosure restricted by GSA ADP Schedule Contract with IBM Corp.

Finding information with Access ThinkPad

Find answers to your questions about your computer and view IBM Web sites by pressing the ThinkPad button shown in the previous illustration to open Access ThinkPad, your on-board computer help center.

Learn about the many features of your ThinkPad computer. ThinkPad Features provides a visual display of your computer and components.

Once you are familiar with the hardware features of your system, use the Tools and Tips category to get the most out of those features like wireless networking, maximizing your battery life, etc... Click Access Help to open a comprehensive help system offering information such as how to change or upgrade the memory in your computer.

Visit these IBM Web sites to join an interactive community of ThinkPad users, download new backgrounds, purchase accessories, or get online support.

Keyword Search provides a quick way to search information in Access Help.

You can view information about your system such as model number in System Details and change the look of your application through Personalize.

iv ThinkPad

A30 Series Service and Troubleshooting Guide

Some of the topics in your help system contain brief video clips that show you how to perform certain tasks, such as replacing your battery, inserting a PC Card, or upgrading your memory.

Finding information with Access ThinkPad v

vi ThinkPad

A30 Series Service and Troubleshooting Guide

Finding information with Access ThinkPad iii

Chapter 1. Overview of your new ThinkPad

computer .............1

Your ThinkPad at a glance .......2

Features..............3

Specifications ............5

Caring for your ThinkPad computer ....6

Chapter 2. Solving computer problems . . 9

Troubleshooting...........10

Diagnosing problems .........10

Problems and solutions ........11

Error messages ..........11

Errors without messages .......14

A password problem ........15

A power switch problem.......15

Keyboard problems ........16

TrackPoint problems ........17

Standby or hibernation problems ....18

Computer screen problems ......21

Battery problems .........22

Hard disk drive problems ......23

Chapter 1. Overview of your new ThinkPad computer

Your ThinkPad at a glance .......2

Features..............3

Specifications ............5

Caring for your ThinkPad computer ....6

Your ThinkPad at a glance

Front view

Rear view

ThinkPad®A30 Series Service and Troubleshooting Guide

Features

Processor

v Mobile Intel

Pentium®III processor-M

Memory

v Built-in: 128MB v Maximum: 1 GB

Storage device

v 2.5-inch hard disk drive: Up to 48 GB, depending on the model

Display

The color display uses TFT technology:

v Size: 14.1 or 15.0 inch, depending on the model v Resolution:

– LCD: Up to 1600-by-1200, depending on the model – External monitor: Up to 2048-by-1536

v Brightness control

Keyboard

v 84-key, 85-key, or 89-key v TrackPoint

v Fn key function v ThinkPad button v Volume control buttons v Web navigation keys v ThinkLight

™

Features

Chapter 1. Overview of your new ThinkPad computer 3

Features

Diskette drive

To get the best performance from your diskette drives, use high-quality diskettes (such as IBM diskettes) that meet or exceed the following standards:

v 1-MB, 3.5-inch, unformatted diskette:

– ANSI (American National Standards Institute) X3.137 – ISO (International Standards Organization) 8860 – ECMA (European Computer Manufacturers Association) 100

v 2-MB, 3.5-inch, unformatted diskette:

– ANSI X3.171 – ISO 9529 – ECMA 125

External interface

v Serial connector (EIA-RS232D) v Parallel connector (IEEE 1284A) v External-monitor connector v PC Card slots (Type I, Type II, or Type III PC Card) v Headphone jack v Line-in jack v Microphone jack v Video-in connector (on some models) v Video-out connector v Universal Serial Bus (USB) connectors v IEEE 1394 connector (on some models)

™

v UltraPort

connector (on some models)

v Infrared port v RJ11 telephone connector (available if the modem feature is installed) v RJ45 Ethernet connector (available if the Ethernet feature is installed)

™

v Ultrabay

2000

v Ultrabay Plus v Expansion connector v Integrated wireless LAN (IEEE 802.11b) feature (on some models)

™

v Integrated Bluetooth

feature (on some models)

ThinkPad®A30 Series Service and Troubleshooting Guide

Specifications

Size

v Width: 329 mm (13.0 in.) v Depth: 272.5 mm (10.8 in.) v Height: 39.6 mm (1.6 in.) to 46.8 mm (1.9 in.)

Environment

v Maximum altitude without pressurization: 3048 m (10,000 ft) v Temperature

– At altitudes up to 2438 m (8000 ft)

- Operating with no diskette: 5° to 35°C (41° to 95°F)

- Operating with a diskette: 10° to 35°C (50° to 95°F)

- Not operating: 5° to 43°C (41° to 110°F)

– At altitudes above 2438 m (8000 ft)

- Maximum operating temperature, 31.3°C (88°F)

Note: When you charge the battery pack, its temperature must be at least

10°C (50°F).

v Relative humidity:

– Operating with no diskette in the drive: 8% to 95% – Operating with a diskette in the drive: 8% to 80%

Heat output

v 72 W (246 Btu/hr) maximum

Power source (ac adapter)

v Sine-wave input at 50 to 60 Hz v Input rating of the ac adapter: 100-240 V ac, 50 to 60 Hz

Battery pack

v Lithium-ion (Li-Ion) battery pack

– Nominal voltage: 10.8 V dc – Capacity: 3.6 AH

Chapter 1. Overview of your new ThinkPad computer 5

Caring for your ThinkPad computer

Though your computer is designed to function reliably in normal work environments, you need to use common sense in handling it. By following these important tips, you will get the most use and enjoyment out of your computer.

Important tips:

Be careful about where and how you work

v Do not leave the base of your computer in contact with your lap or any

part of your body for an extended period when the computer is functioning or when the battery is charging. Your computer dissipates some heat during normal operation. This heat is a function of the level of system activity and battery charge level. Extended contact with your body, even through clothing, could cause discomfort or, eventually, a skin burn.

v Place liquids away from your computer to avoid spills, and keep your

computer away from water (to avoid the danger of electrical shock).

v Store packing materials safely out of the reach of children to prevent the

risk of suffocation from plastic bags.

v Keep your computer away from magnets, activated cellular phones,

electrical appliances, or speakers (within 13cm/5 in).

v Avoid subjecting your computer to extreme temperatures (below 5°C/41°F

or above 35°C/95°F).

Be gentle with your computer

v Avoid placing any objects (including paper) between the display and the

keyboard or under the keyboard.

v Do not drop, bump, scratch, twist, hit, vibrate, push or place heavy objects

on your computer, display, or external devices.

v Your computer display is designed to be opened and used at an angle

slightly greater than 90 degrees. Do not open the display beyond 135 degrees, as this might damage the computer hinge.

Carry your computer properly

v Before moving your computer, be sure to remove any media, turn off

attached devices, and disconnect cords and cables.

v Be sure your computer is in standby or hibernation mode, or turned off,

before moving it. This will prevent damage to the hard disk drive and data loss.

v When picking up your open computer, hold it by the bottom. Do not pick

up or hold your computer by the display.

ThinkPad®A30 Series Service and Troubleshooting Guide

Caring for your ThinkPad computer

v Use a quality carrying case that provides adequate cushion and protection.

Do not pack your computer in a tightly packed suitcase or bag.

Handle storage media and drives properly

v If your computer comes with a diskette drive, avoid inserting diskettes at

an angle and attaching multiple or loose diskette labels, as these can lodge in the drive.

v If your computer comes with a CD or DVD drive, do not touch the surface

of a CD or DVD, or the lens on the CD or DVD tray.

v Wait until you hear the CD or DVD click into the center pivot of the CD or

DVD drive before closing the CD or DVD tray.

v When installing your hard disk, diskette, CD, or DVD drive, follow the

instructions shipped with your hardware, and apply pressure only where needed on the device. See Access ThinkPad, your on-board help system, for information on replacing your hard disk drive (open Access ThinkPad by pressing the ThinkPad button).

Take care in setting passwords

v Remember your passwords. If you forget a supervisor or hard disk

password, IBM will not reset it, and you might have to replace your system board or hard disk drive.

v If you are an administrator, remember that setting a supervisor password

can prevent unauthorized initialization.

Other important tips

v Your computer modem might use only an analog telephone network, or

public-switched telephone network (PSTN). Do not connect the modem to a PBX (private branch exchange) or any other digital telephone extension line because this could damage your modem. Analog phone lines are often used in homes, while digital phone lines are often used in hotels or office buildings. If you are not sure which kind of phone line you are using, contact your telephone company.

v Your computer might have both an Ethernet connector and a modem

connector. If so, be sure to connect your communication cable to the correct one, so your connector is not damaged. See Access ThinkPad, your on-board help system, for information on the location of these connectors (press the ThinkPad button to open Access ThinkPad).

v Register your ThinkPad products with IBM (refer to the Web page:

www.pc.ibm.com/register). This can help authorities return your computer to you if it is lost or stolen. Registering your computer also enables IBM to notify you about possible technical information and upgrades.

v Only an authorized IBM ThinkPad repair technician should disassemble

and repair your computer.

Chapter 1. Overview of your new ThinkPad computer 7

Caring for your ThinkPad computer

v Do not modify or tape the latches to keep the display open or closed. v Take care not to turn your computer over while the ac adapter is plugged

in. This could break the adapter plug.

v Turn off your computer if you are replacing a device in a device bay, or else

verify that the device is warm- or hot-swappable.

v If you exchange drives in your computer, reinstall the plastic bezel faces (if

supplied).

v Store your external and removable hard disk, diskette, CD, and DVD drives

in the appropriate containers or packaging when they are not being used.

Cleaning your computer

Occasionally clean your computer as follows: v Use a soft cloth moistened with nonalkaline detergent to wipe the exterior

of the computer.

v Avoid spraying cleaner directly on the display or the keyboard. v Gently wipe the display with a soft, dry cloth. If you see a scratchlike mark

on your display, it might be a stain transferred from the keyboard or the TrackPoint pointer when the cover was pressed from the outside. Wipe or dust the stain gently with a soft, dry cloth. If the stain remains, moisten a soft, lint-free cloth with water that does not contain impurities, wring out as much of the water as you can, and then wipe the display again. Be sure to dry the display before closing it.

ThinkPad®A30 Series Service and Troubleshooting Guide

Chapter 2. Solving computer problems

Troubleshooting...........10

Diagnosing problems .........10

Problems and solutions ........11

Error messages ..........11

Errors without messages .......14

A password problem ........15

A power switch problem.......15

Keyboard problems ........16

TrackPoint problems ........17

Standby or hibernation problems ....18

Computer screen problems ......21

Battery problems .........22

Hard disk drive problems ......23

Troubleshooting

Access ThinkPad, your on-board help system, provides a full set of suggestions for troubleshooting. For access to that help system, press the ThinkPad button. This troubleshooting section deals only with problems that might prevent you from getting access to Access ThinkPad.

Diagnosing problems

If you have a problem with your computer, you can test it by using PC-Doctor®for Windows®. To run PC-Doctor for Windows, do as follows:

1. Click Start.

2. Move the cursor to Programs (in Windows XP, All Programs) and then to

PC-Doctor for Windows.

3. Click PC-Doctor for Windows.

4. Choose either the Quick Test or the Standard Test.

Attention

Running the Quick Test set can take 10 minutes or longer. Make sure you have time to run the entire test; do not interrupt the test while it is running.

The Quick Test set runs many tests of critical hardware components, but it does not run all of the diagnostic tests in PC-Doctor for Windows. If PC-Doctor for Windows reports that all of the tests in the Quick Test set have been run and that it has found no problems, consider running more of the tests.

If you are preparing to contact IBM for support, be sure to print the test log so that you can rapidly provide information to the help technician.

ThinkPad®A30 Series Service and Troubleshooting Guide

Problems and solutions

Error messages

Notes:

1. In the charts, x can be any character.

2. The version of PC-Doctor referred to here is PC-Doctor for Windows.

Message Solution

0175: Bad CRC1, stop POST task

0187: EAIA data access error

0188: Invalid RFID serialization information area or bad CRC2.

0189: Invalid RFID configuration information area

0190: Critical low-battery error

0195: Security hardware tamper detected

0196: Security hardware removed

0197: Invalid Remote change requested

01C8: More than one modem devices are found; only one is allowed. Remove one of them. Press Esc to continue.

01C9: More than one Ethernet devices are found; only one is allowed. Remove one of them. Press Esc to continue.

The EEPROM checksum is not correct (block #6). Have the computer serviced.

The access to EEPROM failed. Have the computer serviced.

The EEPROM checksum is not correct (block # 0 and 1, or block # 6). The system board should be replaced, and the box serial number needs to be reinstalled. Have the computer serviced.

The EEPROM checksum is not correct (block # 4 and 5). The system board should be replaced, and the UUID needs to be reinstalled. Have the computer serviced.

The computer turned off because the battery is low. Connect the ac adapter to the computer and charge the battery, or replace the battery with a fully charged one.

The Security Chip has been attached to or replaced on your computer. Open the BIOS Setup Utility (using the supervisor password), and clear the Security Chip. If it does not solve this problem, have the computer serviced.

The Security Chip has been removed from your computer. Clear the Security Chip, using the BIOS Setup Utility by entering supervisor password. If it does not solve this problem, have the computer serviced.

The remote configuration for the Security Chip has failed. Confirm the operation and try again.

Remove either a modem Mini-PCI Card or a modem Daughter Card. Otherwise, press Esc to ignore the warning message. If it does not solve this problem, have the computer serviced.

Remove either an Ethernet Mini-PCI Card or an Ethernet Daughter Card. Otherwise, press Esc to ignore the warning message. If it does not solve this problem, have the computer serviced.

Solving computer problems

Chapter 2. Solving computer problems 11

Solving computer problems

Message Solution

0200: Hard disk error The hard disk is not working. Make sure that the hard disk drive is attached

firmly. Run the BIOS Setup Utility; then make sure the hard disk drive is not disabled in the Startup menu.

021x: Keyboard error Make sure that there are no objects placed on the keyboard, or if you have

one, on the external keyboard. Turn off the computer, and turn off all attached devices. Turn on the computer first; then turn on the attached devices.

If you still see the same error code, do the following:

If an external keyboard is connected, do the following: v Turn off the computer and disconnect the external keyboard; then turn on

the computer. Make sure that the built-in keyboard operates correctly. If it does, have the external keyboard serviced.

v Make sure that the external keyboard is connected to the correct

connector.

Test the computer, using PC-Doctor. v If the computer stops during the test, have the computer serviced.

0230: Shadow RAM error The shadow RAM failed. Test your computer’s memory with PC-Doctor. If

you added a memory module just before turning the computer on, reinstall it. Then test the memory with PC-Doctor.

0231: System RAM error The system RAM failed. Test your computer’s memory with PC-Doctor. If

you added a memory module just before turning the computer on, reinstall it. Then test the memory with PC-Doctor.

0232: Extended RAM error

0250: System battery error

0251: System CMOS checksum bad

0260: System timer error Have the computer serviced. 0270: Real time clock

error 0271: Date and time error Neither the date nor the time is set in the computer. Set the date and time,

The extended RAM failed. Test your computer’s memory with PC-Doctor. If you increased memory just before turning the computer on, reinstall it. Then test the memory with PC-Doctor.

The backup battery is depleted. This battery is used to preserve the configuration information, such as date and time, while the computer is turned off. Replace the battery and run IBM BIOS Setup Utility to verify the configuration. If you still have a problem, have the computer serviced.

The system CMOS might have been corrupted by an application program. The computer uses the default settings. Run IBM BIOS Setup Utility to reconfigure the settings. If you still see the same error code, have the computer serviced.

Have the computer serviced.

using the IBM BIOS Setup Utility.

ThinkPad®A30 Series Service and Troubleshooting Guide

Solving computer problems

Message Solution

0280: Previous boot incomplete

02D0: System cache error The cache is disabled. Have the computer serviced. 02F4: EISA CMOS not

writable 02F5: DMA test failed Have the computer serviced. 02F6: Software NMI

failed 02F7: Fail-safe timer NMI

failed The power-on password

prompt

The hard disk password prompt

Your computer was previously unable to complete the boot process. Turn the computer off; then turn it on to start the BIOS Setup Utility. Verify the configuration and then restart the computer either by choosing the Exit Saving Changes option under the Restart item or by pressing F10. If you still see the same error code, have the computer serviced.

Have the computer serviced.

A power-on password or a supervisor password is set. Type the password and press Enter to use the computer. If the power-on password is not accepted, a supervisor password might have been set. Type the supervisor password and press Enter. If you still see the same error message, have the computer serviced.

A hard disk password is set. Type the password and press Enter to use the computer.

If you still see the same error message, have the computer serviced.

Hibernation error The system configuration changed between the time your computer entered

hibernation mode and the time it left this mode, and your computer cannot resume normal operation.

v Restore the system configuration to what it was before your computer

entered hibernation mode.

v If the memory size changed, re-create the hibernation file.

Operating system not found.

Fan error The cooling fan has failed. Have the computer serviced.

Verify the following:

v The hard disk drive is correctly installed. v A startable diskette is in the diskette drive

If the same error message is still displayed, check the boot sequence, using the IBM BIOS Setup Utility.

Chapter 2. Solving computer problems 13

Solving computer problems

Message Solution

EMM386 Not Installed— Unable to Set Page Frame Base Address.

CardBus Configuration Error—Device Disabled

Edit C:\CONFIG.SYS and change a line from

device=C:\WINDOWS\EMM386.EXE RAM

device=C:\WINDOWS\EMM386.EXE NOEMS

and save this file. Press F1 to go to the IBM BIOS Setup Utility. Press F9 and then Enter to

load the default setting.

Press F10 and then Enter to restart the system.

Errors without messages

Problem: When I turn on the machine, nothing appears on the screen and the machine does not beep while starting up.

Note: If you are not sure whether you heard any beeps, turn off the

computer; then turn it on again, and listen again. If you are using an external monitor, refer to External monitor problems in Access ThinkPad, your on-board help system.

Solution: If a power-on password is set, press any key to display the power-on password prompt, and then type the correct password and press Enter.

If the power-on password prompt does not appear, the brightness level might be set to minimum brightness. Adjust the brightness level by pressing the Fn+Home keys.

If the screen still remains blank, make sure that:

v The battery is installed correctly. v The ac adapter is connected to the computer and the power cord is plugged

into a working electrical outlet.

v The computer power is on. (Turn on the power switch again for

confirmation.)

If these items are properly set, and the screen remains blank, have the computer serviced.

Problem: When I turn on the machine, only a white cursor appears on a blank screen.

ThinkPad®A30 Series Service and Troubleshooting Guide

Solution: First, reboot your system by pressing Ctrl+Alt+Del. If that does not work, hold down the power switch for more than 4 seconds. If this does not resolve the problem, you may need to reinstall your operating system.

Problem: My screen goes blank while the computer is on.

Solution: Your screen saver or power management may be enabled. Move the

TrackPoint or press a key to exit the screen saver, or press the power switch to resume from standby or hibernation.

Problem: The DOS full-screen looks smaller.

Solution: If you use a DOS application that supports only 640x480 resolution

(VGA mode), the screen image might look slightly distorted or might appear smaller than the display size. This is to maintain compatibility with other DOS applications. To expand the screen image to the same size as the actual screen, start the ThinkPad Configuration Program and click LCD; then select the Screen expansion function. (The image might still look slightly distorted.)

Note: If your computer has a screen expansion function, you can use the

Fn+F8 keys to expand the screen image.

A password problem

Problem: I forgot my password.

Solving computer problems

Solution: If you forget your power-on password, you must take your computer to an IBM reseller or marketing representative to have the password canceled.

If you forget your hard disk password, IBM will not reset your password or recover data from the hard disk. You must take your computer to an IBM reseller or an IBM marketing representative to have the hard disk drive replaced. Proof of purchase is required, and a fee will be charged for parts and service.

If you forget your supervisor password, IBM will not reset your password. You must take your computer to an IBM reseller or IBM marketing representative to have the system board replaced. Proof of purchase is required, and a fee will be charged for parts and service.

A power switch problem

Problem: The system does not respond, and you cannot turn off the computer.

Solution: Turn off the computer by pressing and holding the power switch for

4 seconds or more. If the system is still not reset, remove the ac adapter and the battery.

Chapter 2. Solving computer problems 15

Solving computer problems

Keyboard problems

Problem: The cursor does not move after the computer returns from one of the power management modes.

Solution: Reboot the system. Make sure you followed the instructions correctly when you installed Windows with the Advanced Power Management (APM) option.

Note: The APM option is supported in Windows 95, Windows 98, or

Windows NT.

Problem: Some or all of the keys on the keyboard do not work.

Solution: If the problem occurred immediately after the computer returned

from standby mode, enter the power-on password if one has been set.

If an external keyboard is connected, the numeric keypad on your computer does not work. Use the numeric keypad on the external keyboard.

If an external numeric keypad or a mouse is connected:

1. Turn off the computer.

2. Remove the external numeric keypad or the mouse.

3. Turn on the computer and try using the keyboard again.

If the keyboard problem is resolved, carefully reconnect the external numeric keypad, external keyboard, or mouse, making sure that you have seated the connectors properly.

If keys on the keyboard still do not work, have the computer serviced.

Problem: A number appears when you type a letter.

Solution: The numeric lock function is on. To disable it, press and hold Shift;

then press NumLk.

Problem: Some or all of the keys on the external numeric keypad do not work.

Solution: Make sure that the external numeric keypad is correctly connected to the computer.

Problem: Some or all of the keys on the external keyboard do not work.

Solution: : If you are using the docking station or the port replicator, make

sure that the keyboard cable is correctly connected to the keyboard connector.

ThinkPad®A30 Series Service and Troubleshooting Guide

+ 62 hidden pages

IBM A30P, A31, A31P TROUBLE

Specifications and Main Features

Frequently Asked Questions

User Manual

Finding information with Access ThinkPad

Contents

Chapter 1. Overview of your new ThinkPad computer

Your ThinkPad at a glance

Features

Specifications

Caring for your ThinkPad computer

Chapter 2. Solving computer problems

Troubleshooting

Diagnosing problems

Problems and solutions

Error messages

Errors without messages

A password problem

A power switch problem

Keyboard problems