IBM Comprehensive Guide to Maintenance and Service Procedures for ThinkPad Hardware

ThinkPad 390E Hardware

Maintenance Manual

Read This First

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

Important		Notes
Ÿ	Only	certified trained personnel should service
	the	computer.

ŸRead the entire FRU service procedures before replacing any FRUs.

ŸUse new nylon-coated screws when you replace FRUs.

Ÿ

Be

extremely

careful

during

write

operations

such

as copying, saving, or formatting.

Drives

in

the

computer that you are servicing might have been

rearranged

or

the drive

startup

sequence

might have

been altered. If you select an incorrect drive, data or

programs

might

be

overwritten.

Ÿ

Replace

FRUs

only

for

the

correct

model.

When

you

replace

a FRU, make sure the model of the

machine

and

FRU part

number

are

correct

by refer-

ring

to

the

FRU

parts

list.

Ÿ

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. FRU

replacement

should

be

considered

only when a recur-

ring

problem

exists.

If

this is suspected, clear the

error

log and

run

the

test

again.

Do

not

replace any

FRUs

if

log

errors

do

not

reappear.

Be careful not to replace a non-defective FRU.

What to Do First

The servicer must include the following in the parts

exchange form or parts return form that is attached to the returned FRU:

1.Name and phone number of servicer

2.Date of service

3.Date when part failed

4.Date of purchase

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

ThinkPad 390E 19