IBM THINKPAD X20, THINKPAD X21, THINKPAD X22, THINKPAD X23, THINKPAD X24 Service and Troubleshooting Guide

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ThinkPad X20, X21, X22, X23,
X24 Hardware Maintenance
Manual

note

Before using this information and the product it
supports, be sure to read the general information
under Chapter 4, “Notices” on page 137

First Edition (March 2002)

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 ANY
WARRANTY OF ANY KIND, EITHER EXPRESS OR
IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE
LIMITED WARRANTIES OF MERCHANTABILITY OR
FITNESS FOR A PARTICULAR PURPOSE. Some states
do not allow disclaimer or express or implied warranties in
certain transactions; therefore, this statement may not
apply to you.

This publication 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 or changes to the products or the programs
described in this publication at any time.

It is possible that this publication may contain references
to, or information about, IBM products (machines and
programs), programming, or services that are not
announced in your country. Such references or information
must not be construed to mean that IBM intends to
announce such IBM products, programming, or services in
your country.

Requests for technical information about IBM products
should be made to your IBM authorized dealer or your IBM
marketing representative.

© Copyright International Business Machines
Corporation 2001. All rights reserved. NotetoUS

Government Users — Documentation related to restricted
rights — Use, duplication, or disclosure is subject to
restrictions set forth in GSA ADP Schedule Contract with
IBM Corp.

Contents

Chapter 1. Introduction ..........1

Importantserviceinformation.........1

FRU replacement strategy ........1

Hard disk drive replacement strategy .....2

How to use error messages ........2

How to read POST error messages ......2

Safety notices: multilingual translations ......3

Safetyinformation............12

General safety ............12

Electricalsafety...........13

Safety inspection guide .........14

Handling electrostatic discharge-sensitive devices 15

Grounding requirements .........16

Laser compliance statement.........17

Laser radiation.............18

Chapter 2. General descriptions .......21

Read this first .............21

Relatedserviceinformation.........24

ServiceWebsite...........24

Product recovery program ........24

Using Recovery CD ..........25

Creating a Recovery Repair diskette .....26

Passwords .............26

Power management ..........28

Checkout guide ............32

Testing the computer ..........34

Detecting system information with PC-Doctor. . . 35

Power system checkout .........38

Chapter 3. ThinkPad X20, X21, X22, X23, X24 . . . 39

Product overview ............42

Specifications ............42

Statusindicators...........45

Fn key combinations ..........47

Symptom-to-FRU index ..........48

Numeric error codes ..........48

Error messages ...........50

Beep symptoms ...........51

LCD-related symptoms .........52

Intermittentproblems..........52

Undetermined problems .........53

FRU replacement notices .........54

Screwnotices............54

Retaining serial numbers.........55

Removing and replacing a FRU........57

1010 Battery pack...........58

1020 DIMM ............59

1030 Backup battery ..........60

1040 Hard disk drive ..........61

iii

1050 Keyboard ...........63

1060 KBD Control Panel Assemble .....67

1070 Mini PCI adapter .........69

1080 CDC adapter ..........70

1090 BDC adapter ..........71

1100 Fan assembly ..........72

1110 Wirelesslan assembly for X22, X23, X24 . . 74

1120 LCD assembly ..........75

1130 Case Keyboard deck ........79

1140 Speaker ............82

1150 PC Card slot assembly .......84

1160IRDAPort...........85

1170 RJ11, RJ45 ...........87

1180 System board ..........89

1190 LCD USB cover..........91

1200 Front bezel ...........92

1210 LCD panel ...........93

Locations ..............98

Front view for X20, X21 .........98

FrontviewforX22 ..........98

Front view for X23, X24 .........99

Rear view for X20, X21 .........101

Rear view for X22, X23, X24 .......101

Bottomview............103

PartsList..............104

X20 series model matrix ........104

X21 series model matrix ........104

X22 series model matrix ........105

X23 series model matrix ........105

X24 series model matrix ........106

LCDFRU.............107

System .............112

Keyboard .............121

Base Cover FRU ..........122

Recovery CDs for X21 Series .......124

Recovery CDs for X22 Series .......126

Recovery CDs for X23 Series .......128

Recovery CDs for X24 Series .......129

Miscellaneous parts ..........131

OptionsFRUlist...........133

Common parts list (X20, X21, X22, X23, X24) 135

Chapter 4. Notices ...........137

Trademarks .............137

iv ThinkPad X20, X21, X22, X23, X24

Chapter 1. Introduction

Important service information

Important

BIOS and device driver fixes are

customer-installable. The BIOS and device drivers

are posted on the IBM support site

http://www.ibm.com/pc/support/

®

Advise customers to contact the IBM

at 800-772-2227 if they need assistance in obtaining

or installing any diskette fixes.

HelpCenter

FRU replacement strategy

Before replacing parts

Ensure that all BIOS and device driver fixes are

installed before replacing any FRUs listed in this

manual.

Use the following strategy to prevent unnecessary FRU
replacement and service expense:

v If you are instructed to replace a FRU, but the

replacement does not correct the problem, reinstall
the original FRU before you continue.

v Some computers have both a processor board and a

system board. If you are instructed to replace either the
processor board or the system board, and the first board
that you replace does not correct the problem, reinstall
the original board, and then replace the other (processor
or system) board.

v If an adapter or device consists of more than one FRU,

any of the FRUs may be the cause of the error. Before
replacing the adapter or device, remove the FRUs, one
by one, to see if the symptoms change. Replace only
the FRU that changed the symptoms.

®

Attention

A customized setup configuration (other than default

settings) may exist on the computer you are

servicing. Running Automatic Configuration may

alter those settings. Note the current configuration

settings (using the View Configuration option); then,

when service has been completed, verify that the

settings are in place.

1

Hard disk drive replacement strategy

Always try to run a low-level format before replacing a hard
disk drive.

Attention

The drive startup sequence in the computer you are
servicing might have been changed. Be extremely
careful during write operations such as copying,
saving, or formatting. If you select an incorrect drive,
data or programs can be overwritten.

How to use error messages

Use the error codes displayed on the screen to diagnose
failures. If more than one error code is displayed, begin the
diagnosis with the first error code. Whatever causes the
first error code may also cause false error codes. If no
error code is displayed, see if the error symptom is listed
in the Symptom-to-FRU Index for the computer you are
servicing.

How to read POST error messages

POST error messages are displayed on the screen as
three, four, five, or eight digits. The error messages that
can be displayed as shorter POST messages are
highlighted in this index. Some digits have one meaning for
SCSI errors and a different meaning for non-SCSI errors.

The following example shows which digits display the
shorter POST error messages and also defines the SCSI
information in each digit of an eight-digit error message.

Shorter POST Messages

00000000

Reserved

Device Code

Logical Unit Number (SCSI)

ID (SCSI)

Size (SCSI)

Slot Number (SCSI)

Each SCSI device is assigned a unique SCSI ID. Duplicate
SCSI ID settings can generate a false error message. Use
the SCSI ID to determine whether an error message is
coming from an internal or an external device.

2 ThinkPad X20, X21, X22, X23, X24

Safety notices: multilingual translations

The following safety notices are provided in English,
French, German, Italian, and Spanish languages.

Safety Notice 1

Before the computer is powered-on after FRU

replacement, make sure all screws, springs, or other

small parts are in place and are not left loose inside

the computer. Verify this by shaking the computer

and listening for rattling sounds. Metallic parts or

metal flakes can cause electrical shorts.

Avant de remettre l’ordinateur sous tension après

remplacement d’une unité en clientèle, vérifiez que

tous les ressorts, vis et autres pièces sont bien en

place et bien fixées. Pour ce faire, secouez l’unité et

assurez-vous qu’aucun bruit suspect ne se produit.

Des pièces métalliques ou des copeaux de métal

pourraient causer un court-circuit.

Bevor nach einem FRU-Austausch der Computer

wieder angeschlossen wird, muβ sichergestellt

werden, daβ keine Schrauben, Federn oder andere

Kleinteile fehlen oder im Gehäuse vergessen

wurden. Der Computer muβ geschüttelt und auf

Klappergeräusche geprüft werden. Metallteile oder

-splitter können Kurzschlüsse erzeugen.

Prima di accendere l’elaboratore dopo che é stata

effettuata la sostituzione di una FRU, accertarsi che

tutte le viti, le molle e tutte le altri parti di piccole

dimensioni siano nella corretta posizione e non

siano sparse all’interno dell’elaboratore. Verificare

ciò scuotendo l’elaboratore e prestando attenzione

ad eventuali rumori; eventuali parti o pezzetti

metallici possono provocare cortocircuiti pericolosi.

Antes de encender el sistema despues de sustituir

una FRU, compruebe que todos los tornillos,

muelles y demás piezas pequeñas se encuentran

en su sitio y no se encuentran sueltas dentro del

sistema. Compruébelo agitando el sistema y

escuchando los posibles ruidos que provocarían.

Las piezas metálicas pueden causar cortocircuitos

eléctricos.

Chapter 1. Introduction 3

Safety Notice 2

Some standby batteries contain a small amount of
nickel and cadmium. Do not disassemble it,
recharge it, throw it into fire or water, or short-circuit
it. Dispose of the battery as required by local
ordinances or regulations. Use only the battery in
the appropriate parts listing. Use of an incorrect
battery can result in ignition or explosion of the
battery.

Certaines batteries de secours contiennent du nickel
et du cadmium. Ne les démontez pas, ne les
rechargez pas, ne les exposez ni au feu ni à l’eau.
Ne les mettez pas en court-circuit. Pour les mettre
au rebut, conformez-vous à la réglementation en
vigueur. Lorsque vous remplacez la pile de
sauvegarde ou celle de l’horloge temps réel, veillez
à n’utiliser que les modèles cités dans la liste de
pièces détachées adéquate. Une batterie ou une
pile inappropriée risque de prendre feu ou
d’exploser.

Die Bereitschaftsbatterie, die sich unter dem
Diskettenlaufwerk befindet, kann geringe Mengen
Nickel und Cadmium enthalten. Sie darf nur durch
die Verkaufsstelle oder den IBM Kundendienst
ausgetauscht werden. Sie darf nicht zerlegt,
wiederaufgeladen, kurzgeschlossen, oder Feuer
oder Wasser ausgesetzt werden. Die Batterie kann
schwere Verbrennungen oder Verätzungen
verursachen. Bei der Entsorgung die örtlichen
Bestimmungen für Sondermüll beachten. Beim
Ersetzen der Bereitschafts- oder Systembatterie nur
Batterien des Typs verwenden, der in der
Ersatzteilliste aufgeführt ist. Der Einsatz falscher
Batterien kann zu Entzündung oder Explosion
führen.

Alcune batterie di riserva contengono una piccola
quantità di nichel e cadmio. Non smontarle,
ricaricarle, gettarle nel fuoco o nell’acqua né
cortocircuitarle. Smaltirle secondo la normativa in
vigore (DPR 915/82, successive disposizioni e
disposizioni locali). Quando si sostituisce la batteria
dell’RTC (real time clock) o la batteria di supporto,
utilizzare soltanto i tipi inseriti nell’appropriato
Catalogo parti. L’impiego di una batteria non adatta
potrebbe determinare l’incendio o l’esplosione della
batteria stessa.

4 ThinkPad X20, X21, X22, X23, X24

Safety Notice 2

Algunas baterías de reserva contienen una pequeña

cantidad de níquel y cadmio. No las desmonte, ni

recargue, ni las eche al fuego o al agua ni las

cortocircuite. Deséchelas tal como dispone la

normativa local. Utilice sólo baterías que se

encuentren en la lista de piezas. La utilizaciónde

una batería no apropiada puede provocar la ignición

o explosión de la misma.

Chapter 1. Introduction 5

Safety Notice 3

The battery pack contains small amounts of nickel.
Do not disassemble it, throw it into fire or water, or
short-circuit it. Dispose of the battery pack as
required by local ordinances or regulations. Use
only the battery in the appropriate parts listing when
replacing the battery pack. Use of an incorrect
battery can result in ignition or explosion of the
battery.

La batterie contient du nickel. Ne la démontez pas,
ne l’exposez ni au feu ni à l’eau. Ne la mettez pas
en court-circuit. Pour la mettre au rebut,
conformez-vous à la réglementation en vigueur.
Lorsque vous remplacez la batterie, veillez à
n’utiliser que les modèles cités dans la liste de
pièces détachées adéquate. En effet, une batterie
inappropriée risque de prendre feu ou d’exploser.

Akkus enthalten geringe Mengen von Nickel. Sie
dürfen nicht zerlegt, wiederaufgeladen,
kurzgeschlossen, oder Feuer oder Wasser
ausgesetzt werden. Bei der Entsorgung die örtlichen
Bestimmungen für Sondermüll beachten. Beim
Ersetzen der Batterie nur Batterien des Typs
verwenden, der in der Ersatzteilliste aufgeführt ist.
Der Einsatz falscher Batterien kann zu Entzündung
oder Explosion führen.

La batteria contiene piccole quantità di nichel. Non
smontarla, gettarla nel fuoco o nell’acqua né
cortocircuitarla. Smaltirla secondo la normativa in
vigore (DPR 915/82, successive disposizioni e
disposizioni locali). Quando si sostituisce la batteria,
utilizzare soltanto i tipi inseriti nell’appropriato
Catalogo parti. L’impiego di una batteria non adatta
potrebbe determinare l’incendio o l’esplosione della
batteria stessa.

Las baterías contienen pequeñas cantidades de
níquel. No las desmonte, ni recargue, ni las eche al
fuego o al agua ni las cortocircuite. Deséchelas tal
como dispone la normativa local. Utilice sólo
baterías que se encuentren en la lista de piezas al
sustituir la batería. La utilización de una bateríano
apropiada puede provocar la ignición o explosiónde
la misma.

6 ThinkPad X20, X21, X22, X23, X24

Safety Notice 4

The lithium battery can cause a fire, explosion, or

severe burn. Do not recharge it, remove its

polarized connector, disassemble it, heat it above

100°C (212°F), incinerate it, or expose its cell

contents to water. Dispose of the battery as required

by local ordinances or regulations. Use only the

battery in the appropriate parts listing. Use of an

incorrect battery can result in ignition or explosion of

the battery.

La pile de sauvegarde contient du lithium. Elle

présente des risques d’incendie, d’explosion ou de

brûlures graves. Ne la rechargez pas, ne retirez pas

son connecteur polarisé et ne la démontez pas. Ne

l’exposez pas à une temperature supérieure à

100°C, ne la faites pas brûleretn’en exposez pas

le contenu à l’eau. Mettez la pile au rebut

conformément à la réglementation en vigueur. Une

pile inappropriée risque de prendre feu ou

d’exploser.

Die Systembatterie ist eine Lithiumbatterie. Sie kann

sich entzünden, explodieren oder schwere

Verbrennungen hervorrufen. Batterien dieses Typs

dürfen nicht aufgeladen, zerlegt, über 100 C erhitzt

oder verbrannt werden. Auch darf ihr Inhalt nicht mit

Wasser in Verbindung gebracht oder der zur

richtigen Polung angebrachte Verbindungsstecker

entfernt werden. Bei der Entsorgung die örtlichen

Bestimmungen für Sondermüll beachten. Beim

Ersetzen der Batterie nur Batterien des Typs

verwenden, der in der Ersatzteilliste aufgeführt ist.

Der Einsatz falscher Batterien kann zu Entzündung

oder Explosion führen.

La batteria di supporto e una batteria al litio e puo

incendiarsi, esplodere o procurare gravi ustioni.

Evitare di ricaricarla, smontarne il connettore

polarizzato, smontarla, riscaldarla ad una

temperatura superiore ai 100 gradi centigradi,

incendiarla o gettarla in acqua. Smaltirla secondo la

normativa in vigore (DPR 915/82, successive

disposizioni e disposizioni locali). L’impiego di una

batteria non adatta potrebbe determinare l’incendio

ol’esplosione della batteria stessa.

Chapter 1. Introduction 7

Safety Notice 4

La bateria de repuesto es una bateria de litio y
puede provocar incendios, explosiones o
quemaduras graves. No la recargue, ni quite el
conector polarizado, ni la desmonte, ni caliente por
encima de los 100°C (212°F), ni la incinere ni
exponga el contenido de sus celdas al agua.
Deséchela tal como dispone la normativa local.

8 ThinkPad X20, X21, X22, X23, X24

Safety Notice 5

If the LCD breaks and the fluid from inside the LCD

gets into your eyes or on your hands, immediately

wash the affected areas with water for at least 15

minutes. Seek medical care if any symptoms from

the fluid are present after washing.

Si le panneau d’affichage à cristaux liquides se

brise et que vous recevez dans les yeux ou sur les

mains une partie du fluide, rincez-les abondamment

pendant au moins quinze minutes. Consultez un

médecin si des symptômes persistent aprèsle

lavage.

Die Leuchtstoffröhre im LCD-Bildschirm enthält

Quecksilber. Bei der Entsorgung die örtlichen

Bestimmungen für Sondermüll beachten. Der

LCD-Bildschirm besteht aus Glas und kann

zerbrechen, wenn er unsachgemäβ behandelt wird

oder der Computer auf den Boden fällt. Wenn der

Bildschirm beschädigt ist und die darin befindliche

Flüssigkeit in Kontakt mit Haut und Augen gerät,

sollten die betroffenen Stellen mindestens 15

Minuten mit Wasser abgespült und bei

Beschwerden anschlieβend ein Arzt aufgesucht

werden.

Nel caso che caso l’LCD si dovesse rompere ed il

liquido in esso contenuto entrasse in contatto con gli

occhi o le mani, lavare immediatamente le parti

interessate con acqua corrente per almeno 15

minuti; poi consultare un medico se i sintomi

dovessero permanere.

Si la LCD se rompe y el fluido de su interior entra

en contacto con sus ojos o sus manos, lave

inmediatamente las áreas afectadas con agua

durante 15 minutos como mínimo. Obtenga atención

medica si se presenta algúnsíntoma del fluido

despues de lavarse.

Chapter 1. Introduction 9

Safety Notice 6

To avoid shock, do not remove the plastic cover that
surrounds the lower portion of the inverter card.

Afin d’éviter tout risque de choc électrique, ne
retirez pas le cache en plastique protégeant la
partie inférieure de la carte d’alimentation.

Aus Sicherheitsgründen die Kunststoffabdeckung,
die den unteren Teil der Spannungswandlerplatine
umgibt, nicht entfernen.

Per evitare scosse elettriche, non rimuovere la
copertura in plastica che avvolge la parte inferiore
della scheda invertitore.

Para evitar descargas, no quite la cubierta de
plástico que rodea la parte baja de la tarjeta
invertida.

Safety Notice 7

Though main batteries have low voltage, a shorted
or grounded battery can produce enough current to
burn combustible materials or personnel.

Bien que le voltage des batteries principales soit
peu élevé, le court-circuit ou la mise à la masse
d’une batterie peut produire suffisamment de
courant pour brûler des matériaux combustibles ou
causer des brûlures corporelles graves.

Obwohl Hauptbatterien eine niedrige Spannung
haben, können sie doch bei Kurzschluβ oder Erdung
genug Strom abgeben, um brennbare Materialien zu
entzünden oder Verletzungen bei Personen
hervorzurufen.

Sebbene le batterie di alimentazione siano a basso
voltaggio, una batteria in corto circuito o a massa
può fornire corrente sufficiente da bruciare materiali
combustibili o provocare ustioni ai tecnici di
manutenzione.

Aunque las baterías principales tienen un voltaje
bajo, una batería cortocircuitada o con contacto a
tierra puede producir la corriente suficiente como
para quemar material combustible o provocar
quemaduras en el personal.

10 ThinkPad X20, X21, X22, X23, X24

Safety Notice 8

Before removing any FRU, power-off the computer,

unplug all power cords from electrical outlets,

remove the battery pack, then disconnect any

interconnecting cables.

Avant de retirer une unité remplaçable en clientèle,

mettez le système hors tension, débranchez tous

les cordons d’alimentation des socles de prise de

courant, retirez la batterie et déconnectez tous les

cordons d’interface.

Die Stromzufuhr muβ abgeschaltet, alle Stromkabel

aus der Steckdose gezogen, der Akku entfernt und

alle Verbindungskabel abgenommen sein, bevor

eine FRU entfernt wird.

Prima di rimuovere qualsiasi FRU, spegnere il

sistema, scollegare dalle prese elettriche tutti i cavi

di alimentazione, rimuovere la batteria e poi

scollegare i cavi di interconnessione.

Antes de quitar una FRU, apague el sistema,

desenchufe todos los cables de las tomas de

corriente eléctrica, quite la batería y, a continuación,

desconecte cualquier cable de conexión entre

dispositivos.

Chapter 1. Introduction 11

Safety information

The following section contains the safety information that
you need to be familiar with before servicing an IBM
mobile computer.

General safety

Follow these rules to ensure general safety:

v Observe good housekeeping in the area of the

machines during and after maintenance.

v When lifting any heavy object:

1. Ensure you can stand safely without slipping.

2. Distribute the weight of the object equally between
your feet.

3. Use a slow lifting force. Never move suddenly or
twist when you attempt to lift.

4. Lift by standing or by pushing up with your leg
muscles; this action removes the strain from the
muscles in your back. Do not attempt to lift any

objects that weigh more than 16 kg (35 lb) or objects
that you think are too heavy for you.

v Do not perform any action that causes hazards, or that

makes the equipment unsafe.

v Before you start the machine, ensure that other service

representatives and the customer’s personnel are not in
a hazardous position.

v Place removed covers and other parts in a safe place,

away from all personnel, while you are servicing the
machine.

v Keep your toolcase away from walk areas so that other

people will not trip over it.

v Do not wear loose clothing that can be trapped in the

moving parts of a machine. Ensure that your sleeves
are fastened or rolled up above your elbows. If your hair
is long, fasten it.

v Insert the ends of your necktie or scarf inside clothing or

fasten it with a non-conductive clip, approximately 8
centimeters (3 inches) from the end.

v Do not wear jewelry, chains, metal-frame eyeglasses, or

metal fasteners for your clothing.
Attention: Metal objects are good electrical

conductors.

v Wear safety glasses when you are hammering, drilling,

soldering, cutting wire, attaching springs, using solvents,
or working in any other conditions that might be
hazardous to your eyes.

12 ThinkPad X20, X21, X22, X23, X24

v After service, reinstall all safety shields, guards, labels,

and ground wires. Replace any safety device that is
worn or defective.

v Reinstall all covers correctly before returning the

machine to the customer.

Electrical safety

Observe the following rules when working on electrical
equipment.

Important

Use only approved tools and test equipment. Some
hand tools have handles covered with a soft
material that does not insulate you when working
with live electrical currents.

Many customers have, near their equipment, rubber
floor mats that contain small conductive fibers to
decrease electrostatic discharges. Do not use this
type of mat to protect yourself from electrical shock.

v Find the room emergency power-off (EPO) switch,

disconnecting switch, or electrical outlet. If an electrical
accident occurs, you can then operate the switch or
unplug the power cord quickly.

v Do not work alone under hazardous conditions or near

equipment that has hazardous voltages.

v Disconnect all power before:

– Performing a mechanical inspection

– Working near power supplies

– Removing or installing main units

v Before you start to work on the machine, unplug the

power cord. If you cannot unplug it, ask the customer to
power-off the wall box that supplies power to the
machine and to lock the wall box in the off position.

v If you need to work on a machine that has exposed

electrical circuits, observe the following precautions:

– Ensure that another person, familiar with the

power-off controls, is near you.
Attention: Another person must be there to switch

off the power, if necessary.

– Use only one hand when working with powered-on

electrical equipment; keep the other hand in your
pocket or behind your back.

Attention: An electrical shock can occur only when
there is a complete circuit. By observing the above
rule, you may prevent a current from passing through
your body.

Chapter 1. Introduction

13

– When using testers, set the controls correctly and

use the approved probe leads and accessories for
that tester.

– Stand on suitable rubber mats (obtained locally, if

necessary) to insulate you from grounds such as
metal floor strips and machine frames.

Observe the special safety precautions when you work
with very high voltages; these instructions are in the
safety sections of maintenance information. Use
extreme care when measuring high voltages.

v Regularly inspect and maintain your electrical hand tools

for safe operational condition.

v Do not use worn or broken tools and testers.

v Never assume that power has been disconnected from

a circuit. First, check that it has been powered off.

v Always look carefully for possible hazards in your work

area. Examples of these hazards are moist floors,
non-grounded power extension cables, power surges,
and missing safety grounds.

v Do not touch live electrical circuits with the reflective

surface of a plastic dental mirror. The surface is
conductive; such touching can cause personal injury and
machine damage.

v Do not service the following parts with the power on

when they are removed from their normal operating
places in a machine:

– Power supply units

– Pumps

– Blowers and fans

– Motor generators

and similar units. (This practice ensures correct
grounding of the units.)

v If an electrical accident occurs:

– Use caution; do not become a victim yourself.

– Switch off power.

– Send another person to get medical aid.

Safety inspection guide

The purpose of this inspection guide is to assist you in
identifying potentially unsafe conditions. As each machine
was designed and built, required safety items were
installed to protect users and service personnel from injury.
This guide addresses only those items. You should use
good judgment to identify potential safety hazards due to
attachment of non-IBM features or options not covered by
this inspection guide.

14 ThinkPad X20, X21, X22, X23, X24

If any unsafe conditions are present, you must determine
how serious the apparent hazard could be and whether
you can continue without first correcting the problem.

Consider these conditions and the safety hazards they
present:

v Electrical hazards, especially primary power (primary

voltage on the frame can cause serious or fatal
electrical shock)

v Explosive hazards, such as a damaged CRT face or a

bulging capacitor

v Mechanical hazards, such as loose or missing hardware

The guide consists of a series of steps presented in a
checklist. Begin the checks with the power off, and the
power cord disconnected.

Checklist:

1. Check exterior covers for damage (loose, broken, or
sharp edges).

2. Power-off the computer. Disconnect the power cord.

3. Check the power cord for:

a. A third-wire ground connector in good condition.

Use a meter to measure third-wire ground
continuity for 0.1 ohm or less between the external
ground pin and frame ground.

b. The power cord should be the type specified in the

parts list.

c. Insulation must not be frayed or worn.

4. Remove the cover.

5. Check for any obvious non-IBM alterations. Use good
judgment as to the safety of any non-IBM alterations.

6. Check inside the unit for any obvious unsafe
conditions, such as metal filings, contamination, water
or other liquids, or signs of fire or smoke damage.

7. Check for worn, frayed, or pinched cables.

8. Check that the power-supply cover fasteners (screws
or rivets) have not been removed or tampered with.

Handling electrostatic discharge-sensitive devices

Any computer part containing transistors or integrated
circuits (ICs) should be considered sensitive to electrostatic
discharge (ESD). ESD damage can occur when there is a
difference in charge between objects. Protect against ESD
damage by equalizing the charge so that the machine, the
part, the work mat, and the person handling the part are all
at the same charge.

Chapter 1. Introduction

15

notes

1. Use product-specific ESD procedures when they
exceed the requirements noted here.

2. Make sure that the ESD protective devices you
use have been certified (ISO 9000) as fully
effective.

When handling ESD-sensitive parts:

v Keep the parts in protective packages until they are

inserted into the product. Avoid contact with other
people.

v Wear a grounded wrist strap against your skin to

eliminate static on your body.

v Prevent the part from touching your clothing. Most

clothing is insulative and retains a charge even when
you are wearing a wrist strap.

v Use the black side of a grounded work mat to provide a

static-free work surface. The mat is especially useful
when handling ESD-sensitive devices.

v Select a grounding system, such as those listed below,

to provide protection that meets the specific service
requirement.

note

The use of a grounding system is desirable but
not required to protect against ESD damage.

– Attach the ESD ground clip to any frame ground,

ground braid, or green-wire ground.

– Use an ESD common ground or reference point

when working on a double-insulated or
battery-operated system. You can use coax or
connector-outside shells on these systems.

– Use the round ground-prong of the AC plug on

AC-operated computers.

Grounding requirements

Electrical grounding of the computer is required for
operator safety and correct system function. Proper
grounding of the electrical outlet can be verified by a
certified electrician.

16 ThinkPad X20, X21, X22, X23, X24

Laser compliance statement

Some IBM Personal Computer models are equipped from
the factory with a CD-ROM drive. CD-ROM drives are also
sold separately as options. The CD-ROM drive is a laser
product. The CD-ROM drive is certified in the U.S. to
conform to the requirements of the Department of Health
and Human Services 21 Code of Federal Regulations
(DHHS 21 CFR) Subchapter J for Class 1 laser products.
Elsewhere, the drive is certified to conform to the
requirements of the International Electrotechnical
Commission (IEC) 825 and CENELEC EN 60 825 for
Class 1 laser products.

When a CD-ROM drive is installed, note the following:

Chapter 1. Introduction 17

CAUTION:

Use of controls or adjustments or performance of
procedures other than those specified herein might
result in hazardous radiation exposure.

O uso de controles, ajustes ou desempenho de
procedimentos diferentes daqueles aqui especificados
pode resultar em perigosa exposição à radiação.

Pour éviter tout risque d’exposition au rayon laser,
respectez les consignes de réglage et d’utilisation des
commandes, ainsi que les procédures décrites.

Werden Steuer- und Einstellelemente anders als hier
festgesetzt verwendet, kann gefährliche
Laserstrahlung auftreten.

L’utilizzo di controlli, regolazioni o l’esecuzione di
procedure diverse da quelle specificate possono
provocare l’esposizione a

El uso de controles o ajustes o la ejecución de
procedimientos distintos de los aquí especificados
puede provocar la exposición a radiaciones
peligrosas.

Laser radiation

Opening the CD-ROM drive could result in exposure to
hazardous laser radiation. There are no serviceable parts
inside the CD-ROM drive. Do not open.

18 ThinkPad X20, X21, X22, X23, X24

Some CD-ROM drives contain an embedded Class 3A or
Class 3B laser diode. Note the following.

Chapter 1. Introduction

19

DANGER

Laser radiation when open. Do not stare into the
beam, do not view directly with optical instruments,
and avoid direct exposure to the beam.

Radiação por raio laser ao abrir. Não olhe fixo no
feixe de luz, não olhe diretamente por meio de
instrumentos óticos e evite exposição direta com o
feixe de luz.

Rayonnement laser si carter ouvert. Évitez de fixer
le faisceau, de le regarder directement avec des
instruments optiques, ou de vous exposer au
rayon.

Laserstrahlung bei geöffnetem Gerät. Nicht direkt
oder über optische Instrumente in den Laserstrahl
sehen und den Strahlungsbereich meiden.

Kinyitáskor lézersugár!Nenézzen bele se szabad
szemmel, se optikai eszközökkel. Kerülje a
sugárnyalábbal valóérintkezést !

Aprendo l’unità vengono emesse radiazioni laser.
Non fissare il fascio, non guardarlo direttamente
con strumenti ottici e evitare l’esposizione diretta al
fascio.

Radiaciónláser al abrir. No mire fijamente ni
examine con instrumental óptico el haz de luz.
Evite la exposición directa al haz.

20 ThinkPad X20, X21, X22, X23, X24

Chapter 2. General descriptions

This chapter includes descriptions for any ThinkPad model
that has the PC-Doctor DOS diagnostics program. Some
descriptions might not apply to your particular computer.

Read this first

Before you go to the checkout guide, be sure to read this
section.

Important notes:
v Only certified trained personnel should service the

computer.

v Read the entire FRU removal and replacement page

before replacing any FRU.

v Use new nylon-coated screws when you replace

FRUs.

v Be extremely careful during such write operations

as copying, saving, or formatting. Drives in the

computer that you are servicing may have had their start
sequence altered. If you select an incorrect drive, data
or programs might be overwritten.

v Replace FRUs only for the correct model. When you

replace a FRU, make sure the model of the machine
and the FRU part number are correct by referring to the
FRU parts list.

v A FRU should not be replaced because of a single,

unreproducible failure. Single failures can occur for a

variety of reasons that have nothing to do with a
hardware defect, such as cosmic radiation, electrostatic
discharge, or software errors. Consider replacing a FRU
only when a problem reoccurs. If you suspect that a
FRU is defective, clear the error log and run the test
again. If the error does not recur, do not replace the
FRU.

v Be careful not to replace a nondefective FRU.

v Service applied by an unauthorized/trained Thinkpad

technician may potentially void your warranty

What to do first: When you do return a FRU, you must
include the following information in the parts exchange
form or parts return form that you attach to it:

1. Name and phone number of servicer

2. Date of service

3. Date on which the machine failed

4. Date of purchase

21

5. Failure symptoms, error codes appearing on the
display, and beep symptoms

6. Procedure index and page number in which the failing
FRU was detected

7. Failing FRU name and part number

8. Machine type, model number, and serial number

9. Customer’s name and address

Note for warranty: During the warranty period, the
customer may be responsible for repair costs if the
computer damage was caused by misuse, accident,
modification, unsuitable physical or operating environment,
or improper maintenance by the customer. The following
list provides some common items that are not covered
under warranty and some symptoms that might indicate
that the system was subjected to stress beyond normal
use.

Before checking problems with the computer, determine
whether the damage is covered under the warranty by
referring to the following:

The following are not covered under warranty:

v LCD panel cracked from the application of excessive

force or from being dropped

v Scratched (cosmetic) parts

v Cracked or broken plastic parts, broken latches, broken

pins, or broken connectors caused by excessive force

v Damage caused by liquid spilled into the system

v Damage caused by the improper insertion of a PC Card

or the installation of an incompatible card

v Damage caused by foreign material in the diskette drive

v Diskette drive damage caused by pressure on the

diskette drive cover or by the insertion of a diskette with
multiple labels

v Damaged or bent diskette eject button

v Fuses blown by attachment of a non-supported device

v Forgotten computer password (making the computer

unusable)

The following symptoms might indicate damage
caused by non-warranted activities:

v Missing parts might be a symptom of unauthorized

service or modification.

v If the spindle of a hard disk drive becomes noisy it may

have been subjected to excessive force or from being
dropped.

22 ThinkPad X20, X21, X22, X23, X24

v I9990303 errors can be caused by exposure to strong

magnetic fields.

Chapter 2. General descriptions

23

Related service information

This section provides information about the following:

v Service Website

v Passwords

v Power management

Service Web site

The latest maintenance diskette is available at

http://www.pc.ibm.com/partner/infotips/

The latest system program service diskette is available at

http://www.pc.ibm.com/us/support/thinkpad/tpopsys.html
or athttp://www.pc.ibm.com/partner/infotips/

Product recovery program

Restoring the Pre-installed Software

To restore the pre-installed software, you can use either
the Product Recovery program or a Recovery CD. The
Product Recovery program is in a section of the hard disk
drive (the Service Partition) that is not displayed by
Windows Explorer. Use the Recovery CD if it was provided
with the computer.

Note: The recovery process might take up to 2 hours.

To use the Product Recovery program to restore the
pre-installed software, do the following:

1. Save all files and shut down the desktop.

2. Turn off the computer.

3. Turn on the computer. Quickly press F11 when this
message is displayed on the screen: ...“To start the

Product Recovery program, press F11”.....This

message is displayed for only a few seconds.

Note: If this message does not appear, you can use a

Recovery Repair diskette to get access to the
Product Recovery program. (see “Creating a
Recovery Repair diskette” on page 26 for
instructions for making the Recovery Repair
diskette)

4. From the list displayed on the screen, select the
operating system you want to recover.

5. Select the recovery options you want, and follow the
instructions on the screen.

24 ThinkPad X20, X21, X22, X23, X24

Using Recovery CD

To create Service Partition and install the preloaded
system from Recovery CD, do the following;

To create Service Partition [SP]:

1. Erase all partitions on the hard-disk drive using FDISK
or similar application.

2. Boot with Recovery CD (and boot diskette if required).

3. A menu will appear stating “Your computer originally

included a Product Recovery program ... Reinstall
the Product Recovery Program? (Y/N) [ ]”.

Note: If the hard-disk drive contains any partitions, you

will not receive this menu - go to step 1.

4. Enter “Y” and Service Partition will be created and
loaded with Product Recovery Program files.

Note: If you do not want to create Service Partition,

press “N”, and then go to the “Install preloaded
system from CD” procedure.

5. Press“ENTER„at next window to continue.

v Service Partition will be created. System will

automatically reboot during this process.

v Recovery process will copy some files to the Service

Partition, PKUNZIP others

v Follow prompts - you may be prompted to change

CDs.

v System will reboot. When completed, continue with

“Install preloaded system from CD” procedure to
install preloaded system.

Install preloaded system from CD:

1. Boot with Recovery CD (and boot diskette if required)

2. If the hard-disk drive is blank, a menu will appear
stating “Your computer originally included a

Product Recovery program ... Reinstall the Product
Recovery Program? (Y/N) [ ]”.

v To install Service Partition, go to step 4 of “To create

Service Partition [SP]” procedure.

v To preload hard-disk drive without installing Service

Partition, press “N”.

3. If a menu appears asking which operating system to
install, highlight proper operating system and press

“ENTER”.

4. A menu will appear stating “Full Recovery:”.Press
“ENTER” to select.

5. Enter “Y” at the three windows which follow.

6. Follow prompts to complete the Recovery Process.

Chapter 2. General descriptions

25

Creating a Recovery Repair diskette

The Recovery Repair diskette is used to recover the
prompt that is needed to access the Product Recovery
program, if the prompt does not appear. Make a Recovery
Repair diskette and save it for future use.

To make a Recovery Repair diskette:

1. Shut down and turn off the computer.

2. Attach the external diskette drive to the computer.

3. At the prompt, press F11. (The option to press F11
appears for only a few seconds. You must press F11
quickly.) The Product Recovery program main menu
appears.

4. If you are using Windows 2000 Professional, you will
be prompted to select the appropriate operating system
setting. This menu does not appear for Windows 98
SE.

5. Select System Utilities from the main menu. Press
Enter.

6. Select Create a Recovery Repair diskette. Press Enter.

7. Follow the on-screen instructions.

8. When the process is completed, label the diskette as
the Recovery Repair diskette and save it for future use.

To use the Recovery Repair diskette:

1. Shut down and turn off the computer.

2. Attach the external diskette drive to the computer.

3. Insert the Recovery Repair diskette into the drive; then
turn on the computer.

4. Follow the on-screen instructions.

Passwords

As many as three passwords may be set for any ThinkPad
computer: the power-on password (POP), the hard disk
password (HDP), and the supervisor password (SVP).

When the power-on password, the hard disk password, or
the supervisor password is used, a password prompt
appears on the screen whenever the computer is turned
on. The computer does not start until the password is
entered.

Power-on password: A power-on password (POP)
protects the system from being powered on by an
unauthorized person. The password must be entered
before an operating system can be booted.

Hard disk password: There are two hard-disk passwords
(HDPs):

26 ThinkPad X20, X21, X22, X23, X24

v User HDP - for the user

v Master HDP - for the system administrator, who can use

it to get access to the hard disk even if the user has
changed the user HDP

Note: There are two modes for the HDP: User only and

Master + User. The Master + User mode requires

two HDPs and is designed for the system
administrator to input both in the same operation.
The system administrator then provides the user
HDP to the system user.

Attention:

If the user HDP is forgotten, check to see if a master HDP
was set. If a master HDP was set and can be recalled, this
will allow access to the hard-disk drive. If no master HDP
is available, IBM does not provide any services to reset
either the user or the master HDPs nor recover data from
the hard-disk drive. The hard-disk drive can be replaced
for a scheduled fee.

Supervisor password: A supervisor password (SVP)
protects the system information stored in the IBM BIOS
Setup Utility . The SVP must be entered in order to access
the IBM BIOS Setup Utility and make changes to system
configuration settings.

Attention:

If the SVP has been forgotten and cannot be made
available to the servicer, there is no service procedure to
reset the password. The system board must be replaced
for a scheduled fee.

How to remove the power-on password: To remove the
POP, do the following:

(A) If SVP is installed and known by the servicer

1. Power on the computer while pressing and holding F1.

2. Enter the supervisor password. The IBM BIOS Setup
Utility menu appears.

3. Select Password, using the cursor keys to move down
the menu.

4. Select Power-on password. A pop-up window opens.

5. Enter the password. When the Enter New Password
field opens, leave it blank and press Enter twice.

6. Press F10; then click Exit.

7. Select Yes in the Setup Configuration window. The
POP has been removed.

Chapter 2. General descriptions

27

(B) If SVP is not installed

1. Turn off the computer.

2. Remove the DIMM cover from the bottom of the
computer.

3. Remove the backup battery. For information on how to
remove the backup battery, see “1030 Backup battery”

on page 60

4. Turn on the computer and wait until the POST ends.
After the POST ends, the password prompt does not
appear. The POP has been removed.

5. Reinstall the backup battery and the DIMM cover.

How to remove the hard-disk password:

Attention:

If User only mode is selected and the user HDP is
forgotten and cannot be made available to the servicer,
IBM does not provide any services to reset the user HDPs
nor recover data from the hard-disk drive. The hard-disk
drive can be replaced for a scheduled fee.

To remove the user HDP that has been forgotten, when
the SVP and master HDP is known,do the following:

1. Power on the computer by pressing and holding F1.

2. Enter the SVP. The IBM BIOS Setup Utility menu
appears.

3. Select Password, using the cursor keys to move down
the menu.

4. Select Hard-disk x password, where x is the letter of
the hard-disk drive. A pop-up window opens.

5. Select either User HDP or Master HDP.

6. Enter the master HDP; then leave the New Password
field blank and press Enter twice.

7. Press F10

8. Select Yes in the Setup Configuration window. Both
user HDP and master HDP will have been removed.

Power management

To reduce power consumption, the computer has three
power management modes: screen blank, standby, and
hibernation.

Screen blank mode: In screen blank mode, the following
occurs:

v The LCD backlight turns off.

v The hard disk drive motor stops.

v The speaker is muted.

28 ThinkPad X20, X21, X22, X23, X24

Note: Screen blank mode in Windows 98 is called standby

mode in Windows 95.

To enter screen blank mode, press Fn + F3. To end screen
blank mode and resume normal operation, press any key.

Standby mode: When the computer enters standby mode,
the following events occur in addition to what occurs in
screen blank mode:

v The LCD is powered off.

v The hard disk drive is powered off.

v The CPU stops.

Note: Screen blank mode in Windows 98 and Windows

2000 is called standby mode in Windows 95.

To enter standby mode, do any of the following:

v Press Fn + F4.

v Close the LCD cover. (To prevent the computer from

entering standby mode when the LCD is closed, click
Will not suspend even if LCD is closed in the Power
Management Properties window. Then only the LCD
turns off.)

In certain circumstances, the computer goes into standby
mode automatically:

v If a ″suspend time″ has been set on the timer, and the

user does not do any operation with the keyboard, the
TrackPoint, the hard disk, the parallel connector, or the
diskette drive within the time set.

v If the AC adapter is plugged in.

v If the battery indicator blinks orange, indicating that the

battery power is low. (Alternatively, if Hibernate when
battery becomes low has been selected in the “Power

Management Properties” window, the computer goes
into hibernation mode.)

Note: Even if you don’t set the low-battery alarm, the

charge indicator lets you know that the battery is
low, and then the computer enters the power-saving
mode automatically. This default low-battery
behavior is independent of the operating system; so
if you have set the low-battery alarm, the computer
may not do what you specified. It chooses either
your setting or the default setting, whichever is

appropriate.
Any one of the following events causes the computer to
resume operation from standby mode:

v The Fn key is pressed.

v The LCD cover is opened.

v The ring indicator (RI) is signaled by a serial device or a

PC Card device. The power switch is turned on.

Chapter 2. General descriptions

29

v The resume timer is set. In Windows 98, the Scheduled

Tasks setting has priority over the Resume on timer

selection in the “Power Management Properties”
window.

Note: The computer does not accept any input

immediately after it enters suspend mode. Wait a
few seconds before taking any action to reenter
operation mode.

Hibernation mode

Note for Windows NT

A Windows NT user cannot create a hibernation file
in a Windows NT system that uses NTFS format,
the Windows NT default format. If you want to use
hibernation mode, you will need to reinstall Windows
NT with FAT format.

In hibernation mode, the following occurs:

v The system status, RAM, VRAM, and setup data are

stored on the hard disk.

v The system is powered off.

Notes:

1. In the ThinkPad Configuration program, the

computer can be set to suspend/hibernate
while docked.

2. The computer cannot enter hibernation mode
when it is powered with AC power and a
communication PC Card is used.

3. If the computer enters the hibernation mode
when it is docked to the docking station, do not
undock it from the docking station before
resuming normal operation. If you do undock it,
then if you try to resume normal operation, you
will get an error message, and you will have to
restart the system.

Any one of the following events causes the computer to
enter hibernation mode:

v The Fn + F12 keys are pressed.

v The power switch is turned off and the mode is set to

Power switch mode Hibernation.

v The timer conditions are satisfied in suspend mode (for

operating systems other than Windows 98).

30 ThinkPad X20, X21, X22, X23, X24

v A critically low battery condition occurs and the mode is

set to Hibernate when battery becomes low.

When the power is turned on, the computer leaves
hibernation mode and resumes operation. The hibernation
file in the boot record on the hard disk drive is read, and
system status is restored from the hard disk drive.

Chapter 2. General descriptions

31

Checkout guide

Use the following procedures as a guide in identifying and
correcting problems with the ThinkPad computer.

Note: The diagnostic tests are intended to test only IBM

products. The use of non-IBM products, prototype
cards, or modified 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.

Testing the computer

The ThinkPad computer has a test program called
PC-Doctor DOS (hereafter called PC-Doctor). You can
detect errors by running the diagnostics test included in
PC-Doctor. This section is an overview of the procedure.
For details that depend on model-unique functions, refer to
“Product overview” on page 42

For some possible configurations of the computer,
PC-Doctor might not run correctly. To avoid this problem,
you need to initialize the computer setup by running the
IBM BIOS Setup Utility before you run PC-Doctor. In the
IBM BIOS Setup Utility screen, press F9, Enter, F10, then

Enter.

Note: When you initialize the computer configuration,

some devices are disabled, such as the serial port.
If you test one of these devices, you will need to
enable it by using PS2.EXE.

PC-Doctor cannot be used to test a device that is in the
docking station. If a device is in the Ultrabay 2000 or
connected to the USB connector of the docking station,
remove it and install it in the Ultrabay 2000 or connect it to
the USB connector of the computer. Then test it with
PC-Doctor.

To run the test, do as follows:

Note: In the following procedure, you can select an item

not only with the arrow keys, but also with the
TrackPoint. Instead of pressing Enter, click the left
button.

1. Insert the PC-Doctor disk into the diskette drive; then
power on the computer.

32 ThinkPad X20, X21, X22, X23, X24

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 48.

On the first screen, select the model and press Enter.
Follow the instructions on the screen.

2. The main panel of PC-Doctor appears.

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

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

The options on the test menu are as follows:

Diagnostics Interactive Tests

v Run Normal Test

v Run Quick Test

v CPU/Coprocessor

v Systemboard

v Video Adapter

v Serial Ports

v Parallel Ports

v Fixed Disks

v Diskette Drives

v Other Devices

v ZIP Drive

v LS-120/240 Drive

v Wireless LAN (*)

v Memory Test-Full

v Memory Test-Quick

v Keyboard

v Video

v Internal Speaker

v Mouse

v Joystick Test

v Diskette

v System Load

v CD-ROM/DVD Test

v Stereo Speaker

v 802.11 Wireless Radio Test

(*)

Chapter 2. General descriptions 33

Notes:

v In the Keyboard test in Interactive tests, the Fn key is

scanned only once. Because of this, each key should be held
down for at least 2 seconds or it will not be sensed.

v The sound card is not recognized in the Stereo Speaker in the

Interactive Tests. To test it, use the audio device test in the
Other Devices (Diagnostics).

v Video Adapter test supports only the LCD display on

ThinkPad. Before running PC-Doctor DOS, detach the external
Monitor.

v To test ZIP Drive or LS-120 Drive, each media is needed to be

inserted before start testing.

v Wireless LAN test is only for some models. Some model do

not have them.

v To test Digital Signature Chip, the chip must be enabled and

initialized.

v When legacy Floppy Drives is Enabled in the BIOS Setup

Utility, Diskette Drives test is activated even if no diskette
drive is attached to the ThinkPad.

v There are 5 kinds of modem test in Other Devices test menu.

Please check first which modem device you want to test as
belows.

Lucent Modem (M2) Loopback

Lucent Modem (M2)
Dialtone/DTMF

Lucent Soft Modem Loopback

Lucent Soft Modem Dialtone

Intel Modem Register

Intel Modem Loopback/DTMF

Intel SP Modem Register

Intel SP Modem
Loopback/DTMF

3Com MiniPCI Modem Test

3Com MiniPCI Dialtone Test

Lucent Modem

Software Modem used in
Wireless Combo Card

Intel combo / Xircom Depop
Combo Card

Intel SP Combo Card

3Com Combo Card

4. Run the applicable function test.

5. Follow the instructions on the screen. If there is a
problem, PC-Doctor shows messages describing it.

6. To exit the test, select Quit-Exit Diag. To cancel the
test, press Esc.

Note: After executing PC-Doctor, check the system

time/date and reset them if needed.

34 ThinkPad X20, X21, X22, X23, X24

Detecting system information with PC-Doctor

PC-Doctor can detect the following system information:

Hardware Info:

v System Configuration

v Memory Contents

v Physical Disk Drives

v Logical Disk Drives

v VGA Information

v IDE Drive Info

v PCI Information

v PNPISA Info

v SMBIOS Info

v VESA LCD Info

Utility:

v Run External Tests

v Surface Scan Hard Disk

v Benchmark System

v DOS Shell

v Tech Support Form

v Battery Rundown

v View Test Log

v Print Log

v Save Log

v Full Erase Hard Drive

v Quick Erase Hard Drive

Power system checkout

To verify the symptom of a problem, do the following:

1. Power off the computer.

2. Remove the battery pack.

3. Connect the AC adapter.

4. Check that power is supplied when you power on the
computer.

5. Power off the computer.

6. Disconnect the AC adapter and install the charged
battery pack.

7. Check that the battery pack supplies power when you
power on the computer.

If you suspect a power problem, see the appropriate one
of the following power supply checkouts:

Chapter 2. General descriptions

35

v ″Checking the AC adapter″ 36

v ″Checking operational charging″ 36

v ″Checking the battery pack″ 37

v ″Checking the backup battery″ 37

Checking the AC adapter: If the computer fails only when
the AC adapter is used, check the following:

v If the power problem occurs only when the port

replicator is used, replace the port replicator.

v If the power-on indicator does not turn on, check the

power cord of the AC adapter for correct continuity and
installation.

v If the computer does not charge during operation, go to

″Checking operational charging.″

1. Unplug the AC adapter cable from the computer and
measure the output voltage at the plug of the AC
adapter cable. See the following figure:

2

1

(16-10V)

Pin Voltage (V dc)

1 +15.5 to +17.0

2 Ground

If the voltage is not correct, replace the AC adapter. If
the voltage is acceptable, do the following:

v Replace the system board.

v If the problem persists, go to “Product overview” on

page 42.

Note: Noise from the AC adapter does not always

indicate a defect.

Checking operational charging: To check operational
charging, use a discharged battery pack or a battery pack
that has less than 50% of the total power remaining when
installed in the computer.

Perform operational charging. If the battery status indicator
or icon does not turn on, remove the battery pack and let it
return to room temperature. Reinstall the battery pack.

36 ThinkPad X20, X21, X22, X23, X24

If the charge indicator or icon still does not turn on, replace
the battery pack. If the charge indicator still does not turn
on, replace the system board. Then reinstall the battery
pack. If the reinstalled battery pack has not been charged,
go to the next section.

Checking the battery pack: Battery charging does not
start until the Fuel Gauge shows that less than 95% of the
total power remains; under this condition the battery pack
can charge to 100% of its capacity. This protects the
battery pack from being overcharged or from having a
shortened life.

Note: If the battery pack becomes hot, it may not be able

to charge. Remove it from the computer and leave it
at room temperature for a while. After it cools down,
reinstall and recharge it.

To check the battery pack, do the following:

1. Power off the computer.

2. Remove the battery pack and measure the voltage
between battery terminals 1 (+) and 4 (-). See the
following figure:

1(+)

2

3

4(-)

Terminal Voltage (V dc)

1 + 0 to + 12.6 (6-cell) +0 to 16.8(4-cell)

4 Ground (-)

3. If the voltage is less than +11.0 V dc, the battery pack
has been discharged.

4. If the voltage is more than +11.0 V dc, measure the
resistance between battery terminals 3 and 4. The
resistance between battery terminals 3 and 4 must be
from 4 to 30k ohms.

Note: Recharging will take at least 3 hours, even if the

indicator does not turn on.
If the voltage is still less than +11.0 V dc after
recharging, replace the battery.

Checking the backup battery: Do the following:

1. Power off the computer, and unplug the AC adapter
from it.

Chapter 2. General descriptions

37

2. Turn the computer upside down.

3. Remove the backup battery (see “1030 Backup battery”
on page 60).

4. Measure the voltage of the backup battery. See the

following figure.

@

Red(+)

Blac

k(-)

Wire Voltage (V dc)

Red +2.5 to +3.2

Black Ground

a. If the voltage is correct, replace the system board.

b. If the voltage is not correct, replace the backup

battery.

c. If the backup battery discharges quickly after

replacement, replace the system board.

38 ThinkPad X20, X21, X22, X23, X24

Chapter 3. ThinkPad X20, X21, X22, X23, X24

Product overview ............42

Specifications ............42

Statusindicators...........45

Fn key combinations ..........47

Symptom-to-FRU index ..........48

Numeric error codes ..........48

Error messages ...........50

Beep symptoms ...........51

No beep symptoms .........51

LCD-related symptoms .........52

Intermittentproblems..........52

Undetermined problems .........53

FRU replacement notices .........54

Screwnotices............54

Retaining serial numbers.........55

Restoring the serial number of the system unit 55

RetainingtheUUID.........56

Removing and replacing a FRU........57

1010 Battery pack...........58

1020 DIMM ............59

1030 Backup battery ..........60

1040 Hard disk drive ..........61

1050 Keyboard ...........63

For X20, X21 ...........63

For X22, X23, X24 .........65

1060 KBD Control Panel Assemble .....67

1070 Mini PCI adapter .........69

For X20, X21 ...........69

For X22, X23, X24 .........69

1080 CDC adapter ..........70

For X22, X23, X24 .........71

1090 BDC adapter ..........71

For X23, X24 ...........72

1100 Fan assembly ..........72

For X20, X21 ...........72

For X22, X23 ...........73

ForX24.............73

1110 Wirelesslan assembly for X22, X23, X24 . . 74

1120 LCD assembly ..........75

For X20, X21 ...........76

For X22, X23, X24 .........78

1130 Case Keyboard deck ........79

For X20, X21 ...........80

For X22, X23, X24 .........81

1140 Speaker ............82

For X20, X21 ...........82

For X22, X23, X24 .........83

1150 PC Card slot assembly .......84

For X20, X21 ...........84

39

For X22, X23, X24 .........85

1160IRDAPort...........85

For X22, X23, X24 .........86

1170 RJ11, RJ45 ...........87

For X20, X21 ...........87

For X22, X23, X24 .........88

1180 System board ..........89

For X20, X21 ...........89

For X22, X23 ...........90

ForX24.............90

1190 LCD USB cover..........91

1200 Front bezel ...........92

1210 LCD panel ...........93

XGA for X20, X21 ..........94

SVGA for X20, X21 .........95

XGA for X22, X23, X24 ........97

Locations ..............98

Front view for X20, X21 .........98

FrontviewforX22 ..........98

Front view for X23, X24 .........99

Rear view for X20, X21 .........101

Rear view for X22, X23, X24 .......101

Bottomview............103

PartsList..............104

X20 series model matrix ........104

X21 series model matrix ........104

X22 series model matrix ........105

X23 series model matrix ........105

X24 series model matrix ........106

LCDFRU.............107

12.1-inch XGA TFT X20, X21 ......107

12.1-inch SVGA TFT ........108

12.1-inch XGA TFT X22, X23, X24 ....111

System .............112

For X20, X21 ...........112

ForX22............114

ForX23............117

ForX24............120

Keyboard .............121

For X20, X21 ...........121

For X22, X23, X24 .........121

Base Cover FRU ..........122

ForX20............122

ForX21............123

ForX22............123

ForX23............123

ForX24............124

Recovery CDs for X21 Series .......124

Windows 98 recovery CDs .......124

Windows 2000 recovery CDs ......125

Windows 2000/Windows NT recovery CDs 125

Windows Me recovery CDs ......126

Recovery CDs for X22 Series .......126

40 ThinkPad X20, X21, X22, X23, X24

Windows 98 recovery CDs .......126

Windows 2000 recovery CDs ......126

Windows XP Pro recovery CDs .....127

Windows XP Home recovery CDs ....127

Recovery CDs for X23 Series .......128

Windows 2000 recovery CDs ......128

Windows XP Pro recovery CDs .....128

Windows XP Home recovery CDs ....129

Recovery CDs for X24 Series .......129

Windows 2000 recovery CDs ......129

Windows XP Pro recovery CDs .....130

Windows XP Home recovery CDs ....131

Miscellaneous parts ..........131

For X20, X21 ...........131

For X22, X23 ...........132

ForX24............133

OptionsFRUlist...........133

For X20, X21 ...........133

For X22, X23, X24 .........134

Common parts list (X20, X21, X22, X23, X24) 135

Tools.............135

Power code (system) ........136

Chapter 3. ThinkPad X20, X21, X22, X23, X24

41

Product overview

This section presents the following product-unique
information:

v Specifications

v Status indicators

v Fn key combinations

Specifications

The following table lists the specifications of the ThinkPad
X20, X21, X22, X23, X24 series:

Feature Description
Processor X20, X21

®

v Intel

mobile Pentium®ΙΙΙ 700MHz, L2

256–KB cache

®

Celeron processor 600MHz, L2

v Intel

128–KB cache

®

Celeron processor 500MHz, L2

v Intel

128–KB cache

X22

v Intel®mobile Pentium®ΙΙΙ-M 733MHz,

L2 512KB cache

®

mobile Pentium®ΙΙΙ-M 800MHz,

v Intel

L2 512KB cache

X23

v Intel®mobile Pentium®ΙΙΙ-M 800MHz,

L2 512KB cache

v Intel®mobile Pentium®ΙΙΙ-M 866MHz,

L2 512KB cache

X24

v Intel®mobile Pentium®ΙΙΙ-M 1.06GHz,

L2 512KB cache

®

mobile Pentium®ΙΙΙ-M 1.13GHz,

v Intel

L2 512KB cache

Bus architecture X20, X21

v PCI BUS

X22, X23, X24

v Hub Architecture

v PCI / LPC BUS

42 ThinkPad X20, X21, X22, X23, X24

Memory (standard) X20, X21

v 64 MB (on the system board)

v 128 MB (on the system board)

X22, X23, X24

v 128 MB (on the system board)

v 256 MB (on the system board plus

128 MB DIMM)

Memory (optional) X20, X21

v 64 MB, 128 MB, or 256 MB SDRAM

card (maximum of 320/384 MB)

X22, X23, X24

v 64 MB, 128 MB, 256 MB or 512 MB

SDRAM card (maximum of 640 MB)

CMOS RAM X20, X21

v 114 bytes +4 Kbytes

X22, X23, X24

v 256bytes

Display X20, X21

v 12.1-inch, 16M colors SVGA

(800×600 resolution) TFT color LCD

v 12.1-inch, 16M colors XGA

(1024×768 resolution) TFT color LCD

X22, X23, X24

v 12.1-inch, 16M colors XGA

(1024×768 resolution) TFT color LCD

Hard disk drive X20, X21

v 10GB, 20GB

X22

10GB, 15GB, 20GB, 30GB

X23, X24

20GB, 30GB

I/O port X20, X21

v USB, RJ11, RJ45, VGA, Mic, Line-in,

Headphone, Docking, 1394 (Some
Models)

X22, X23, X24

USB, RJ11, RJ45, VGA, Mic, IrDA,
Line-in, Headphone, Docking, 1394
(Some Models)

Internal modem X20, X21, X22, X23, X24

v V.90 D/F

Chapter 3. ThinkPad X20, X21, X22, X23, X24 43

Audio X20, X21

v CS4281/CS4297A Mono Speaker

X22, X23, X24

CS4299 Mono Speaker

PC Card X20, X21, X22, X23, X24

T2, Cardbus

AC adapter X20, X21

72W AC/DC

X22, X23, X24

56W AC/DC

Status indicators

The system status indicators show the current computer
status in different colors (green or orange):

3

2

1

TM

5

6

7

9

8

T

M

4

Indicator Meaning

1 Battery Green:The battery is fully charged.

Blinking green: The battery has enough

power to operate but is charging.

Orange: The battery power is low. The
battery is charging.

Blinking orange: The battery needs
charging.

44 ThinkPad X20, X21, X22, X23, X24

2 Standby status Green:The computer is in standby mode.

Blinking green: The computer is entering

standby mode or hibernation mode, or is
resuming normal operation.

3 Bluetooth(X23,
X24 Bluetooth
Model Only)

4 Bluetooth
power button(X23,
X24 Bluetooth
Model Only)

5 Drive in use Green:Data is read from or written to the

6 Num lock Green:The numeric keypad on the keyboard

7 Caps lock Green:Caps Lock mode is enabled.
8 Scroll lock Green:Arrow keys can be used as

9 Power on Green:The power is on.

Green:The Integrated Bluetooth features are
on.

Blinking green:The Integrated Bluetooth
features are functioning.

Press this button to turn the IBM Integrated
Bluetooth on and off.

hard disk drive, diskette drive, or drive in the
Ultrabay 2000.

is enabled.

screen-scroll function keys.

The following table shows the test for each FRU.

FRU Applicable test

System board

Power Diagnostics --> Other Devices --> IBM AC

LCD unit

1. Diagnostics --> CPU/Coprocessor

2. Diagnostics --> Systemboard

Adapter, IBM Battery

1. Diagnostics --> Video Adapter

2. Interactive Tests --> Video

Chapter 3. ThinkPad X20, X21, X22, X23, X24 45

Modem

Audio

Speaker Interactive Tests --> Internal Speaker
PC Card slots Diagnostic --> System Board --> PCMCIA,

Keyboard

TrackPoint or
pointing device

Hard disk drive Diagnostics --> Fixed Disks

Diskette drive

CD-ROM or DVD
drive

1. Make sure the modem is set up
correctly.

2. Replace the modem jack and the
modem card in turn, and run the
following test in Diagnostics --> Other

Devices.

a. Lucent Modem (M2) Loopback

b. Lucent Modem (M2) Dialtone/DTM

c. Lucent Soft Modem Loopback

d. Lucent Soft Modem Dialtone

e. Intel Modem Register

f. Intel Modem Loopback/DTMF

g. Intel SP Modem Register

h. Intel SP Modem Loopback/DTMF

i. 3Com MiniPCI Modem Test

j. 3Com MiniPCI Dialtone Test

1. Interactive Tests --> Internal Speaker

2. Diagnostics --> Other Devices -->

Crystal SoundFusion Test

PCMCIA External Loop

1. Diagnostics --> System Board -->
Keyboard

2. Interactive Test --> Keyboard

If the TrackPoint does not work, check the
configuration in the ThinkPad Configuration
program. If the TrackPoint is disabled, select
Enable to enable it.

After you use the TrackPoint, the pointer
may drift on the screen for a short time. This
drift can occur when a slight, steady
pressure is applied to the TrackPoint pointer.
This symptom is not a hardware problem.
No service action is necessary if the pointer
stops after a short time

If enabling the TrackPoint does not correct
the problem, continue with the following.

v Interactive Tests --> Mouse

1. Diagnostics --> Diskette Drives

2. Interactive Tests --> Diskette

1. Diagnostics --> Other Devices -->

CD-ROM/DVD

2. Interactive Tests --> CD-ROM/DVD
Test

46 ThinkPad X20, X21, X22, X23, X24

Memory

Fan

1. If two DIMMs are installed, remove one

of them and run Diagnostics -->
Memory Test - Quick.

2. If the problem does not recur, replace
the DIMM, remove the other one, and
run the test again.

3. If the test does not detect the error, run
Diagnostics --> Memory Test - Full.

1. Turn on the computer and check the air
turbulence at the louver near the power
switch.

2. Run Diagnostics --> Other Devices -->

IBM Fan.

Fn key combinations

The following table shows the function of each combination
of Fn with a function key.

The Fn key works independently from the operating
system.

Key Combination Result
Fn+F1 Reserved.
Fn+F2 Reserved.
Fn+F3 Standby mode.
Fn+F4 Suspend mode.
Fn+F5 Reserved.
Fn+F6 Reserved.
Fn+F7 Switch between the LCD, the external

Fn+F8 Reserved.
Fn+F9 Reserved.
Fn + F12 Hibernation mode.
Fn + PgUp ThinkLight On/Off.
Fn + Home The LCD becomes brighter.
Fn + End The LCD becomes less bright.

monitor, and both the LCD and external
monitor.

Chapter 3. ThinkPad X20, X21, X22, X23, X24 47

Symptom-to-FRU index

The symptom-to-FRU index lists symptoms and errors and
their possible causes. The most likely cause is listed first,
in boldface type.

Note: Do the FRU replacement or other actions in the

sequence shown in the column headed ″FRU or
action, in Sequence″. If replacing a FRU does not
solve the problem, put the original part back in the
computer. Do not replace a non-defective FRU.

This index can also help you determine, during regular
servicing, what FRUs are likely to need to be replaced
next.

A numeric error is displayed for each error detected in
POST or system operation. In the displays, n can be any
number.

If no numeric code is displayed, check the narrative
descriptions of symptoms. If the symptom is not described
there, go to “Intermittent problems” on page 52.

Note: For an IBM devices not supported by diagnostic

codes in the ThinkPad notebook computers, see the
manual for that device.

Numeric error codes

Symptom or error FRU or action, in sequence
0175

Bad CRC1, stop POST task.
The EEPROM checksum is not
correct.

0187

EAIA data access error

0190

Critical low battery error.

0193

RF antenna has been removed.
0194The computer has been

carried through a security gate.

1. System board.

1. System board.

1. Critical low battery error.

Charge the battery pack.

2. Battery pack.

1. Enter the supervisor

password.

1. Enter the supervisor
password.

48 ThinkPad X20, X21, X22, X23, X24

0200

Fixed disk failure

021x

Monitor type does not match
CMOS

0220

Shadow RAM failure at offset
nnnn

0232

Extended RAM failure at offset
nnnn

0250

System battery is dead—
replace and run setup

0251

System CMOS checksum
bad—Default configuration used

0252

Password checksum bad.

0260

System timer error

0270

Real time clock error

0271

Date and time error

0280

Boot incomplete error— Default
configuration used

1. Reseat the hard disk

drive.

2. Load Setup Defaults in IBM
BIOS Setup Utility.

3. Hard disk drive.

4. System board.

1. Load Setup Defaults in

IBM BIOS Setup Utility.

1. System board.

1. DIMM.

2. System board.

1. Replace the backup

battery and run IBM BIOS
Setup Utility to reset the
time and date.

1. Replace the backup
battery and run IBM BIOS
Setup Utility to reset the
time and date..

1. Reset the password by
running IBM BIOS Setup
Utility.

1. Replace the backup
battery and run IBM BIOS
Setup Utility to reset the
time and date.

2. System board.

1. Replace the backup

battery and run IBM BIOS
Setup Utility to reset the
time and date.

2. System board.

1. Run IBM BIOS Setup

Utility to reset the time
and date..

1. Load Setup Defaults in
IBM BIOS Setup Utility.

2. DIMM.

3. System board.

Chapter 3. ThinkPad X20, X21, X22, X23, X24 49

02F4

EISA CMOS not writable.

02F5

DIMM test failure

02F6

Software NMI failure

02F7

Fail-safe timer NMI failure

1. Load Setup Defaults in

IBM BIOS Setup
Utility.Replace the backup

battery.

2. System board.

1. DIMM.

2. System board.

1. DIMM.

2. System board.

1. DIMM.

2. System board.

Error messages

Symptom or error FRU or action, in sequence

Device address conflict

Allocation error for device

Failing bits: nnnn

Invalid system configuration
data

I/O device IRQ conflict

Operating system not found

1. Load Setup Defaults in

IBM BIOS Setup Utility.

2. Backup battery.

3. System board.

1. Load Setup Defaults in

IBM BIOS Setup Utility.

2. Backup battery.

3. System board.

1. DIMM.

2. System board.

1. DIMM.

2. System board.

1. Load Setup Defaults in

IBM BIOS Setup Utility.

2. Backup battery.

3. System board.

1. Enter IBM BIOS Setup

Utility and see whether
the hard disk drive and
the diskette drive are
properly identified.

2. Diskette drive.

3. Hard disk drive.

4. System board.

50 ThinkPad X20, X21, X22, X23, X24

Hibernation error

Operating system not found

Fan error

1. Restore the system

configuration to what it
was the before the
computer entered
hibernation mode.

2. If memory size has been
changed, re-create the
hibernation file.

1. Reseat the hard disk

drive.

2. Check the boot sequence
by use of IBM BIOS Setup

1. Fan.

Beep symptoms

Symptom or error FRU or action, in sequence

One beep and a blank,
unreadable, or flashing LCD

One long and two short beeps,
and a blank or unreadable LCD

Two short beeps with error
codes

Two short beeps with blank
screen

Only cursor appears

1. Reseat the LCD

connector.

2. LCD assembly.

3. System board.

1. System board.

2. LCD assembly.

POST error. See “Numeric
error codes” on page 48

1. System board.

1. Reinstall operating

system.

No beep symptoms

Symptom or error FRU or action, in sequence

No beep, power-on indicator
on, LCD blank, and no POST

No beep, power-on indicator
on, and LCD blank during
POST

No beep during POST, but
system runs correctly

Chapter 3. ThinkPad X20, X21, X22, X23, X24 51

1. Make sure that every

connector is connected
tightly and correctly.

2. DIMM.

3. System board.

1. Reseat DIMM.

2. System board.

1. Speaker.

The power-on password prompt A power-on password or a

The hard disk password prompt A hard disk password is set.

The DOS-full screen looks
smaller.

supervisor password is set.
Type the password and press
Enter.

Type the password and press
Enter.

Start the ThinkPad
Configuration program and set
the Screen expansion
function.

LCD-related symptoms

Important:

The TFT LCD for the notebook computer contains many
thin-film transistors (TFTs). A small number of dots that are
missing, discolored, or always lighted is characteristic of
TFT LCD technology, but excessive pixel problems can
cause viewing concerns. The LCD should be replaced if
the number of missing, discolored, or lighted dots in any
background is:

v SVGA(X20, X21): 5 or more bright dots, 5 or more dark

dots, or a total of 9 or more bright and dark dots.

v XGA(X22, X23, X24): 8 or more bright dots, 8 or more

dark dots, or a total of 9 or more bright and dark dots.

Symptom or error FRU or action, in sequence

No beep, power-on indicator
on, and a blank LCD during
POST

v LCD backlight not working

v LCD too dark

v LCD brightness cannot be

adjusted

v LCD contrast cannot be

adjusted

v LCD screen unreadable

v Characters missing pixels

v Screen abnormal

v Wrong color displayed

v Horizontal or vertical lines

displayed on LCD

1. System board.

1. Reseat the LCD

connectors.

2. LCD assembly.

3. System board.

1. See important note for

″LCD-related symptoms″.

2. Reseat all LCD connectors.

3. LCD assembly.

1. LCD assembly.

Intermittent problems

Intermittent system hang problems can be due to a variety
of causes that have nothing to do with a hardware defect,

52 ThinkPad X20, X21, X22, X23, X24

such as: cosmic radiation, electrostatic discharge, or
software errors. FRU replacement should be considered
only when a recurring problem exists.

When analyzing an intermittent problem, do the following:

1. Run the diagnostic test for the system board in loop

mode at least 10 times.

2. If no error is detected, do not replace any FRUs.

3. If any error is detected, replace the FRU shown by the
FRU code. Re-run the test to verify that no more errors
exist.

Undetermined problems

If the diagnostic tests did not identify which adapter or
device failed, which installed devices are incorrect, whether
or not a short circuit is suspected, or if the system is
inoperative. Follow these procedures to isolate the failing
FRU (do not isolate FRUs that have no defects).

Verify that all attached devices are supported by the
computer.

Verify that the power supply being used at the time of the
failure is operating correctly. (See “Power system
checkout” on page 35)

1. Power off the computer.

2. Visually check each FRU for damage. Replace any
damaged FRU.

3. Remove or disconnect all of the following devices:

a. Non-IBM devices

b. Devices attached to the port replicator

c. Printer, mouse, and other external devices

d. Battery pack

e. Hard disk drive

f. External diskette drive

g. DIMM

h. CD-ROM and diskette drive in the UltraBase X2

i. PC Cards

4. Power on the computer.

5. Determine whether the problem has changed.

6. If the problem does not recur, reconnect the removed
devices one at a time until you find the failing FRU.

7. If the problem remains, replace the following FRUs one
at a time (do not replace a non-defective FRU):

a. System board

b. LCD assembly

Chapter 3. ThinkPad X20, X21, X22, X23, X24

53

FRU replacement notices

This section contains notices related to removing and
replacing parts. Read this section carefully before replacing
any FRU.

Screw notices

Loose screws can cause a reliability problem. The IBM
ThinkPad computer addresses this problem with special
nylon-coated screws that have the following characteristics:

v They maintain tight connections.

v They do not easily come loose, even with shock or

vibration.

v They are harder to tighten.

v They should be used only once.

Do the following when you service this machine:

v Keep the screw kit (P/N 05K4841) in your tool bag.

v Always use new screws.

v Use a torque screwdriver if you have one.

Tighten screws as follows:

v Plastic to plastic

Turn an additional 90 degrees after the screw head
touches the surface of the plastic part:

90 degrees more

(Cross section)

v Logic card to plastic

54 ThinkPad X20, X21, X22, X23, X24

Turn an additional 180 degrees after the screw head
touches the surface of the logic card:

180 degrees more

(Cross section)

v Torque driver

If you have a torque driver, refer to the ″Torque″ column
with each step.

v Make sure you use the correct screw. If you have a

torque screwdriver, tighten all screws firmly to the torque
shown in the table. Never use a screw that you

removed. Use a new one. Make sure the screws are
tightened firmly

Retaining serial numbers

This section includes the following descriptions:

v ″Restoring the serial number of the system unit″

v ″Retaining the UUID″

Restoring the serial number of the system unit

When the computer was manufactured, the EEPROM on
the system board was loaded with the serial numbers of
the system and all major components. The numbers need
to remain the same throughout the life of the computer.

If you replace the system board, you must restore serial
number of the system unit to its original value.

Before replacing the system board, save the original serial
number by doing the following:

1. Install the ThinkPad Hardware Maintenance Diskette
Version 1.60, and restart the computer.

2. From the main menu, select 1. Set System

Identification.

3. Select 2. Read S/N data from EEPROM.

The serial number for each device is displayed. Write
down the serial number of the system unit, designated as
follows:

20:System unit serial number

Chapter 3. ThinkPad X20, X21, X22, X23, X24

55

After you have replaced the system board, restore the
serial number by doing the following:

1. Install the ThinkPad Hardware Maintenance Diskette
Version 1.60 and restart the computer.

2. From the main menu, select 1. Set System

Identification.

3. Select 1. Add S/N data from EEPROM.

Follow the instructions on the screen.

Note: The serial number of the system unit is written

on the label attached on the bottom of the
computer.

Retaining the UUID

The Universally Unique Identifier (UUID) is a 128-bit
number uniquely assigned to your computer at production
and stored in the EEPROM of your system board. The
algorithm that generates the unique number is designed to
provide unique IDs until the year A.D. 3400. No two
computers in the world have the same number.

When you replace the system board, you must set the
UUID on the new system board as follows:

1. Install the ThinkPad Hardware Maintenance Diskette
Version 1.60, and restart the computer.

2. Select 4. Assign UUID from the main menu. A new
UUID is created and written. If a valid UUID already
exists, it is not overwritten.

56 ThinkPad X20, X21, X22, X23, X24

Removing and replacing a FRU

This section presents information and drawings for use in
removing and replacing a FRU. Be sure to observe the
following general rules:

1. Do not try to service the computer unless you have
been trained and certified. An untrained person runs
the risk of damaging parts.

2. Before replacing any FRU, review “FRU replacement
notices” on page 54.

3. Begin by removing any FRUs that have to be removed
before the failing FRU. Any such FRUs are listed at the
top of the page. Remove them in the order in which
they are listed.

4. Follow the correct sequence in the steps for removing
the FRU, as indicated in the drawings by the numbers
in square callouts.

5. When turning a screw to replace a FRU, turn it in the
direction indicated by the arrow in the drawing.

6. When removing the FRU, move it in the direction
indicated by the arrow in the drawing.

7. To put the new FRU in place, reverse the removal
procedure and follow any notes that pertain to
replacement. For information about connecting and
arranging internal cables, see “Locations” on page 98.

8. When replacing a FRU, use the correct screw as
shown in the procedures.

CAUTION:

Before removing any FRU, power off the computer,
unplug all power cords from electrical outlets, remove
the battery pack, and then disconnect any
interconnecting cables.

CAUTION:

The battery consists of small amount of nickel. Do not
disassemble it, throw it into fire or water, or
short-circuit it. Dispose of the battery pack as required
by local ordinances or regulations.

Chapter 3. ThinkPad X20, X21, X22, X23, X24

57

Attention:

Before the computer is powered on after FRU
replacement, make sure all screws, springs, and other
small parts are in place and are not loose inside the
computer. Verify this by shaking the computer gently and
listening for rattling sounds. Metallic parts or metal flakes
can cause electrical short circuits.

Attention:

The system board is sensitive, and can be damaged by
electrostatic discharge. Establish personal grounding by
touching a ground point with one hand before touching
these units.

You must use an electrostatic discharge (ESD) strap (P/N

6405959) to establish personal grounding.

1010 Battery pack

1

2

58 ThinkPad X20, X21, X22, X23, X24

1020 DIMM

v Battery pack (1010)

1

2

Note: Loosen the screw 1 but do not remove it.

Step Screw (quantity) Torque

1 M2 × 3.4 mm,

Nylock-coated (1) BK

14.7 Ncm (1.5 kgfcm)

4

3

Chapter 3. ThinkPad X20, X21, X22, X23, X24 59

1030 Backup battery

v Battery pack (1010)

v DIMM (1020)

CAUTION:
The backup battery is a lithium battery and can cause
a fire, an explosion, or severe burns. Do not recharge
it, remove its polarized connector, disassemble it, heat
it above 100°C (212°F), incinerate it, or expose its cell
contents to water. Dispose of the battery as required
by local ordinances or regulations. The use of an
incorrect battery can result in ignition or explosion of
the battery.

60 ThinkPad X20, X21, X22, X23, X24

1040 Hard disk drive

v Battery pack (1010)

Attention: Do not drop the hard disk drive or apply
any shock to it. The hard disk drive is sensitive to

physical shock. Incorrect handling can cause damage and
permanent loss of data. Before removing the drive, have
the user make a backup copy of all the information on the
drive if possible. Never remove the drive while the system
is operating or is in suspend mode.

1

2

Note: The hard disk is attached to the cover.

Step Screw (quantity) Torque

1 M3 × 3.5mm,

Nylock-coated (1) BK

19.6 Ncm (2 kgfcm)

1

1

1

When installing: Make sure that the HDD connector is
firmly connected.

Step Screw (quantity) Torque

1 M3 ×3 mm (4) Red 19.6 Ncm (2 kgfcm)

Chapter 3. ThinkPad X20, X21, X22, X23, X24 61

1

62 ThinkPad X20, X21, X22, X23, X24

1050 Keyboard

v Battery pack (1010)

v Hard Disk Drive (1040)

For X20, X21

1

Step Screw (quantity) Torque

1 M2 × 4.5 mm,

Nylock-coated (4) BK

19.6 Ncm (2 kgfcm)

Chapter 3. ThinkPad X20, X21, X22, X23, X24 63

When installing: When installing the keyboard, do as
follows:

1. Install the new keyboard, following the directions in the
figure. Make sure that the keyboard edges, shown in
the figure as (A), (B), (C), (D)and (E), are under the
frame.

A

B

C

D

E

64 ThinkPad X20, X21, X22, X23, X24

2. Align the tabs of the keyboard with the corresponding
slots; then press the keyboard until it snaps into place.

For X22, X23, X24

1

Step Screw (quantity) Torque

1 M2 × 7 mm, Nylock-coated

(3) BK

Chapter 3. ThinkPad X20, X21, X22, X23, X24 65

19.6 Ncm (2 kgfcm)

When installing: When installing the keyboard, do as
follows:

1. Install the new keyboard, following the directions in the
figure. Make sure that the keyboard edges, shown in
the figure as (A), (B), (C), (D)and (E), are under the

66 ThinkPad X20, X21, X22, X23, X24

frame.

A

B

C

D

E

2. Align the tabs of the keyboard with the corresponding
slots; then press the keyboard until it snaps into place.

1060 KBD Control Panel Assemble

v Battery pack (1010)

v Keyboard assembly (1050)

Chapter 3. ThinkPad X20, X21, X22, X23, X24 67

2

2

2

1

1

1

1. Align the KBD Control Panel hooks with the
corresponding slots like the picture.

2. Press the KBD Control Panel until its snaps fit.

68 ThinkPad X20, X21, X22, X23, X24

1070 Mini PCI adapter

For X20, X21

v Battery pack (1010)

v Keyboard assembly (1050)

6

For X22, X23, X24

v Battery pack (1010)

v Keyboard assembly (1050)

Chapter 3. ThinkPad X20, X21, X22, X23, X24

69

6

1080 CDC adapter

For X22, X23, X24

v Battery pack (1010)

v Keyboard assembly (1050)

FRU P/N

Antenna RF Connector removal
tool

08K7159

70 ThinkPad X20, X21, X22, X23, X24

1a

1

Step Screw (quantity) Torque

1a M2 × 3.5mm (2)

Nylock-coated Silver

19.6 Ncm (2 kgfcm)

2

1090 BDC adapter

For X23, X24

v Battery pack (1010)

v Keyboard assembly (1050)

Chapter 3. ThinkPad X20, X21, X22, X23, X24

71

1

2

4a

4

3

Step Screw (quantity) Torque

4a M2 × 3.5mm (2)

Nylock-coated Silver

19.6 Ncm (2 kgfcm)

1100 Fan assembly

v Battery pack (1010)

v Keyboard assembly (1050)

For X20, X21

d

a
P
k

n

i
h
T

Step Screw (quantity) Torque

1 M2 × 3mm (4) White 19.6 Ncm (2 kgfcm)

1a M2 × 6mm, Nylock-coated

(1) BK

19.6 Ncm (2 kgfcm)

72 ThinkPad X20, X21, X22, X23, X24

For X22, X23

Step Screw (quantity) Torque

1 M2 × 3.5mm (4) Silver 19.6 Ncm (2 kgfcm)

1a M2 × 6mm, Nylock-coated

(1) BK

19.6 Ncm (2 kgfcm)

For X24

Step Screw (quantity) Torque

1a M2 × 6mm, Nylock-coated

(1) BK

19.6 Ncm (2 kgfcm)

Chapter 3. ThinkPad X20, X21, X22, X23, X24 73

1110 Wirelesslan assembly for X22, X23, X24

v Battery pack (1010)

v Keyboard assembly (1050)

1

2

2

2

m

m

Step Antena Color Wireless LAN Board

1 Gray Color Main (J1)

2 Black Color Aux (J2)

10mm

74 ThinkPad X20, X21, X22, X23, X24

1120 LCD assembly

v Battery pack (1010)

v Keyboard assembly (1050)

v CDC adapter (1080)

v BDC adapter (1090)

v Wirelesslan assembly (1110)

For X20, X21

1

Chapter 3. ThinkPad X20, X21, X22, X23, X24 75

2

d
a

P
k
n
i

h

T

d
a

P

k
n
i

h

T

Step Screw (quantity) Torque

1 M2.6 × 4mm (2) BK 29.4 Ncm (3 kgfcm)

2 M2 × 8mm,

Nylock-coated(2) BK

29.4 Ncm (3 kgfcm)

76 ThinkPad X20, X21, X22, X23, X24

For X22, X23, X24

1

2

d

a

P
k
n
i

h

T

Chapter 3. ThinkPad X20, X21, X22, X23, X24 77

d

a
P
k

n
i
h

T

Step Screw (quantity) Torque

1 M2.6 × 4mm (4) BK 29.4 Ncm (3 kgfcm)

2 M2 × 8mm,

Nylock-coated(2) BK

29.4 Ncm (3 kgfcm)

78 ThinkPad X20, X21, X22, X23, X24

1130 Case Keyboard deck

v Battery pack (1010)

v Keyboard assembly (1050)

v CDC adapter (1080)

v BDC adapter (1090)

v Fan assembly (1100)

v Wirelesslan assembly (1110)

v LCD assembly (1120)

For X20, X21

1

1a

1a

Step Screw (quantity) Torque

1 M2 × 3.5mm,

1a M2 × 6mm, Nylock-coated

Nylock-coated (5) BK

(3) BK

Chapter 3. ThinkPad X20, X21, X22, X23, X24 79

19.6 Ncm (2 kgfcm)

19.6 Ncm (2 kgfcm)

2

3

4

Case Keyboard deck up; then remove it

Step Screw (quantity) Torque

2 M2 × 6mm, Nylock-coated

(4) BK

19.6 Ncm (2 kgfcm)

For X22, X23, X24

1a

1a

1

Step Screw (quantity) Torque

1 M2 × 3.5mm,

1a M2 × 6mm, Nylock-coated

Nylock-coated (3) BK

(5) BK

19.6 Ncm (2 kgfcm)

19.6 Ncm (2 kgfcm)

80 ThinkPad X20, X21, X22, X23, X24

2

3

Case Keyboard deck up; then remove it

Step Screw (quantity) Torque

2 M2 × 6mm, Nylock-coated

(4) BK

19.6 Ncm (2 kgfcm)

Chapter 3. ThinkPad X20, X21, X22, X23, X24 81

1140 Speaker

v Battery pack (1010)

v Keyboard assembly (1050)

v CDC adapter (1080)

v BDC adapter (1090)

v Fan assembly (1100)

v Wirelesslan assembly (1110)

v LCD assembly (1120)

v Case keyboard deck (1120)

For X20, X21

2

1

Step Screw (quantity) Torque

1 M2 × 3mm, Nylock-coated

(2) BK

19.6 Ncm (2 kgfcm)

5

4

3

When installing: Make sure that you fasten the connector
firmly.

82 ThinkPad X20, X21, X22, X23, X24

For X22, X23, X24

1

Step Screw (quantity) Torque

1 M2 × 3.5mm,

Nylock-coated (2) Silver

5

19.6 Ncm (2 kgfcm)

4

44

3

3

When installing: Make sure that you fasten the connector
firmly.

Chapter 3. ThinkPad X20, X21, X22, X23, X24

83

1150 PC Card slot assembly

v Battery pack (1010)

v Keyboard assembly (1050)

v CDC adapter (1080)

v BDC adapter (1090)

v Fan assembly (1100)

v Wirelesslan assembly (11100)

v LCD assembly (1120)

v Case keyboard deck (1130)

v Speaker (1140)

For X20, X21

1

1a

2

Step Screw (quantity) Torque

1 M2 × 3mm (2) White 14.7 Ncm (1.5 kgfcm)

1a M2 × 6mm, Nylock-coated

(2) BK

19.6 Ncm (2 kgfcm)

84 ThinkPad X20, X21, X22, X23, X24

For X22, X23, X24

1

1a

2

Step Screw (quantity) Torque

1 M2 × 3.5mm (2) Silver 14.7 Ncm (1.5 kgfcm)

1a M2 × 6mm, Nylock-coated

(2) BK

19.6 Ncm (2 kgfcm)

1160 IRDA Port

v Battery pack (1010)

v Keyboard assembly (1050)

v CDC adapter (1080)

v BDC adapter (1090)

v Fan assembly (1100)

v Wirelesslan assembly (1110)

v LCD assembly (1120)

v Case keyboard deck (1130)

v Speaker (1140)

v PC Card slot assembly (1150)

Chapter 3. ThinkPad X20, X21, X22, X23, X24

85

For X22, X23, X24

1

Step Screw (quantity) Torque

1 M2 × 3.5mm (2)

Nylock-coated Silver

19.6 Ncm (2 kgfcm)

86 ThinkPad X20, X21, X22, X23, X24

1170 RJ11, RJ45

v Battery pack (1010)

v Keyboard assembly (1050)

v CDC adapter (1080)

v BDC adapter (1090)

v Fan assembly (1100)

v Wirelesslan assembly (1110)

v LCD assembly (1120)

v Case keyboard deck (1130)

v Speaker (1140)

v PC Card slot assembly (1150)

v IRDA Port (1160)

For X20, X21

4

2

3

1

Step Screw (quantity) Torque

1 M2 × 6mm, Nylock-coated

(2) BK

Chapter 3. ThinkPad X20, X21, X22, X23, X24 87

19.6 Ncm (2 kgfcm)

For X22, X23, X24

4

2

1

3

Step Screw (quantity) Torque

1 M2 × 6mm, Nylock-coated

(1) BK

19.6 Ncm (2 kgfcm)

88 ThinkPad X20, X21, X22, X23, X24

1180 System board

v Battery pack (1010)

v Keyboard assembly (1050)

v CDC adapter (1080)

v BDC adapter (1090)

v Fan assembly (1100)

v Wirelesslan assembly (1110)

v LCD assembly (1120)

v Case keyboard deck (1130)

v Speaker (1140)

v PC Card slot assembly (1150)

v IRDA Port (1160)

v RJ11, RJ45 (1170)

note

CF dummy socket is needed to be removed before
planar replacement.

For X20, X21

1

Step Screw (quantity) Torque

1 M2 × 3mm (1) White 19.6 Ncm (2 kgfcm)

Chapter 3. ThinkPad X20, X21, X22, X23, X24 89

For X22, X23

1

Step Screw (quantity) Torque

1 M2 × 3.5mm (1) Silver 19.6 Ncm (2 kgfcm)

For X24

1

2

Step Screw (quantity) Torque

1 M2 × 3.5mm (1) Silver 19.6 Ncm (2 kgfcm)

2 M2 × 3mm (1) White 19.6 Ncm (2 kgfcm)

90 ThinkPad X20, X21, X22, X23, X24

1190 LCD USB cover

1200 Front bezel

v Battery pack (1010)

v Keyboard assembly (1050)

v Wirelesslan assembly (1110)

v LCD assembly (1120)

2

1

1

1

Chapter 3. ThinkPad X20, X21, X22, X23, X24 91

Step Screw (quantity) Torque

1 M2.6 × 5mm (3) BK 29.4 Ncm (3 kgfcm)

92 ThinkPad X20, X21, X22, X23, X24

1210 LCD panel

v Battery pack (1010)

v Keyboard assembly (1050)

v Wirelesslan assembly (1110)

v LCD assembly (1120)

v Front bezel (1200)

XGA for X20, X21

1

2

1

1

Step Screw (quantity) Torque

1 M2 × 3.5mm (5) BK 19.6 Ncm (2 kgfcm)

2 M2.6 × 4mm (2) BK 29.4 Ncm (3 kgfcm)

Step Screw (quantity) Torque

5 M2 × 3mm (4) WH 19.6 Ncm (2 kgfcm)

Chapter 3. ThinkPad X20, X21, X22, X23, X24 93

Step Screw (quantity) Torque

1 M2 × 3.5mm (2) BK 19.6 Ncm (2 kgfcm)

SVGA for X20, X21

1

2

3

Step Screw (quantity) Torque

1 M2 × 2.7mm (4) White 19.6 Ncm (2 kgfcm)

2 M2 × 3.5mm (1) BK 19.6 Ncm (2 kgfcm)

3 M2.6 × 4mm (1) BK 29.4 Ncm (3 kgfcm)

94 ThinkPad X20, X21, X22, X23, X24

2

1

3

3

4

1

Step Screw (quantity) Torque

1 M2 × 3.5mm (2) BK 19.6 Ncm (2 kgfcm)

Chapter 3. ThinkPad X20, X21, X22, X23, X24 95