IBM Thinkpad A20mp A21mp A22mp Manual

							Electrical safety
Observe the following rules when working on electrical
equipment.
ImportantUse 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.
vFind 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.
vDo not work alone under hazardous conditions or near
equipment that has hazardous voltages.
vDisconnect all power before:
–Performing a mechanical inspection
–Working near power supplies
–Removing or installing main units
vBefore 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.
vIf you need to work on a machine that hasexposed
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.
–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.
Safety information
Introduction15 
						

							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.
vRegularly inspect and maintain your electrical hand tools
for safe operational condition.
vDo not use worn or broken tools and testers.
vNever assumethat power has been disconnected from
a circuit. First,checkthat it has been powered off.
vAlways look carefully for possible hazards in your work
area. Examples of these hazards are moist floors,
nongrounded power extension cables, power surges,
and missing safety grounds.
vDo 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.
vDo not service the following partswith 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.)
vIf 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.
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:
vElectrical hazards, especially primary power (primary
voltage on the frame can cause serious or fatal
electrical shock)
vExplosive hazards, such as a damaged CRT face or a
bulging capacitor
Safety information
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							vMechanical hazards, such as loose or missing hardware
To determine whether there are any potentially unsafe
conditions, use the following checklist at the beginning of
every service task. 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.
Notes1. 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:
vKeep the parts in protective packages until they are
inserted into the product.
vAvoid contact with other people.
Safety information
Introduction17 
						

							vWear a grounded wrist strap against your skin to
eliminate static on your body.
vPrevent the part from touching your clothing. Most
clothing is insulative and retains a charge even when
you are wearing a wrist strap.
vUse 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.
vSelect a grounding system, such as those listed below,
to provide protection that meets the specific service
requirement.
NoteThe 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.
Laser compliance statement
Some IBM Personal Computer models are equipped from
the factory with an optical storage device; such as a
CD-ROM drive or DVD-ROM drive. They are also sold
separately as options. The 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.
Safety information
18ThinkPad A20m/p, A21m/p, A22m/p 
						

							When a CD-ROM drive, DVD drive or the other laser
product is installed, note the following:
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 exposiçãoàradiação.
Pouréviter 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 ejecuciónde
procedimientos distintos de los aquíespecificados
puede provocar la exposición a radiaciones peligrosas.
Laser compliance statement
Introduction19 
						

							Opening the CD-ROM drive, DVD-ROM drive or the other
optical storage device could result in exposure to
hazardous laser radiation. There are no serviceable parts
inside those drives.Do not open.
Some CD-ROM drives, DVD-ROM drives or the other
optical storage devices contain an embedded Class 3A or
Class 3B laser diode. Note the following:
Laser compliance statement
20ThinkPad A20m/p, A21m/p, A22m/p 
						

							DANGER
Emits visible and invisible 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
instrumentosóticos 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
oderüber 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’unitàvengono 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 instrumentalóptico el haz de luz.
Evite la exposición directa al haz.
Laser compliance statement
Introduction21 
						

							Laser compliance statement
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							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 notesvOnly certified trained personnel should
service the computer.
vRead the entire FRU removal and replacement
page before replacing any FRU.
vUse new nylon-coated screws when you
replace FRUs.
vBe extremely careful during such write
operations as copying, saving, or formatting.
Drives in the computer that you are servicing
sequence might have been altered. If you select
an incorrect drive, data or programs might be
overwritten.
vReplace 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.
vA 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 recurs. 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.
vBe careful not to replace a nondefective FRU.
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
__ 5. Failure symptoms, error codes appearing on the
display, and beep symptoms
© Copyright IBM Corp. 2001
23  
						

							__ 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:
vLCD panel cracked from the application of excessive
force or from being dropped
vScratched (cosmetic) parts
vDistortion, deformation or discoloration of the cosmetic
parts
vCracked or broken plastic parts, broken latches, broken
pins, or broken connectors caused by excessive force
vDamage caused by liquid spilled into the system
vDamage caused by the improper insertion of a PC Card
or the installation of an incompatible card
vDamage caused by foreign material in the diskette drive
vDiskette drive damage caused by pressure on the
diskette drive cover or by the insertion of a diskette with
multiple labels
vDamaged or bent diskette eject button
vFuses blown by attachment of a nonsupported device
vForgotten computer password (making the computer
unusable)
vSticky keys caused by spilling a liquid onto the keyboard
The following symptoms might indicate damage
caused by nonwarranted activities:
vMissing parts might be a symptom of unauthorized
service or modification.
vIf the spindle of a hard-disk drive becomes noisy, it may
have been subjected to excessive force, or dropped.
Read this first
24ThinkPad A20m/p, A21m/p, A22m/p