FRU Removals and Replacements
This section contains information about removals and
replacements.
Do not damage any part. Only certified and trained
personnel should service the computer.
The arrows in the “Removals and Replacements”
section show the direction of movement to remove a
FRU, or to turn a screw to release the FRU. The
arrows are marked in numeric order, in square
callouts, to show the correct sequence of removal.
When other FRUs must be removed before the failing
FRU is removed, they are listed at the top of the
page.
To replace a FRU, reverse the removal procedure
and follow any notes that pertain to replacement.
See “Locations” for internal cable connections and
arrangement information.
When replacing a FRU, use the correct screw size as
shown in the procedures.
CAUTION:
Before removing any FRU, turn off the computer,
unplug all power cords from the electrical outlets,
remove the battery pack, and then disconnect any
interconnecting cables.
CAUTION:
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.
Attention: 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 short circuits.
Attention: The system board is sensitive to, 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.
Important Notice
This machine uses special nylon-coated screws with the
following characteristics:
They maintain tight connection.
They do not easily come loose, even with shock or
vibration.

But:

They need additional force to tighten.
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