General Descriptions; Read This First; What To Do First - IBM ThinkPad T20 Hardware Maintenance Manual

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
sequence might have been 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 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.
v Be 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
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