1150 System Board, Fan Assembly, 34-Mm Expresscard Reader, And Base Cover - Lenovo ThinkPad T420s Hardware Maintenance Manual

1150 System board, fan assembly, 34-mm ExpressCard reader, and
base cover
Important notices for handling the system board:
When handling the system board, read the following:
• The system board has an accelerometer, which can be broken when several thousands of G-forces
are applied.
Note: Dropping a system board from a height of as little as 6 inches so that it falls flat on a hard bench
can subject the accelerometer to as much as 6,000 G's of shock.
• Be careful not to drop the system board on a bench top that has a hard surface, such as metal, wood, or
composite.
• If a system board is dropped, test it using PC-Doctor for DOS if the system supports PC-Doctor for DOS,
to make sure that the HDD Active Protection
Note: If the test shows that the HDD Active Protection system is not functioning, be sure to document the
drop in any reject report, and replace the system board.
• Avoid rough handling of any kind.
• At every point in the process, be sure not to drop or stack the system board.
• If you put a system board down, be sure to put it only on a padded surface such as an ESD mat or a
corrugated conductive material.
If the system supports PC-Doctor for DOS, after replacing the system board, run PC-Doctor for DOS to
make sure that HDD Active Protection system still functions. The procedure is as follows:
1. Place the computer on a horizontal surface.
2. Run Diagnostics ➙ ThinkPad Devices ➙ HDD Active Protection Test.
Attention: Do not apply physical shock to the computer while the test is running.
For access, remove these FRUs, in order:
• "1010 Battery pack" on page 68
• "1020 Serial Ultrabay Slim device or travel bezel" on page 69
• "1030 Solid-state drive (SSD) or hard disk drive (HDD)" on page 70
• "1040 DIMM" on page 72
• "1050 PCI Express Mini Card for wireless LAN" on page 74
• "1060 PCI Express Mini Card for wireless WAN" on page 77
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Chapter 8
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Removing and replacing a FRU
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