FRU Service Procedures
Review the following procedures before replacing any
FRU.
LCD FRU Replacement Notice:
The TFT LCD
for the notebook computer contains over 2,359,296 thin-
film transistors (TFTs). A small number of missing, discol-
ored, or lighted dots (on all the time) 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 8 or more.
Replacing the System Board:
When you
replace the system board, restore the system unit serial
number using the VPD Data Utility and reassign the UUID
using the Flash UUID Utility in the ThinkPad 390/i Series
1700 CE Utility Diskette.
Note: Do not power off the computer while restoring the
VPD.
Screw Notices:
When you service this machine, do
the following,
Keep the screw kit (P/N 12J0808) in your tool bag.
Always use new screws. Plastic screws cannot be
reused.
Use a torque screwdriver if possible.
Screw Tightening Information:
Loose screws
can cause a reliability problem. The IBM ThinkPad com-
puter addresses this problem with nylon-coated screws.
Tighten screws as follows,
Plastic to plastic
Turn an additional
90 degrees after
the screw head
touches the
surface of the
plastic part.
Logic card to plastic
Turn an additional
180 degrees after
the screw head
touches the
surface of the logic
card.
Torque driver
If you have a
torque driver, refer
to the torque
instructions with
each step.
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ThinkPad 390/i Series 1700
