Before removing the system board, follow these steps:
1.Shut down the computer. If you are unsure whether the computer is off or in Hibernation, turn the computer on, and then shut it down through the operating system.
2.Disconnect all external devices connected to the computer.
3.Disconnect the power from the computer by first unplugging the power cord from the AC outlet, and then unplugging the AC adapter from the computer.
4.Remove the battery (see Battery on page 47).
5.Remove the following components:
a.Bottom door (see Bottom door on page 49).
b.Hard drive (see Hard drive on page 52)
c.Optical drive (see Optical drive on page 50)
d.Modem module (see Modem module on page 76)
e.Keyboard (see Keyboard on page 63)
f.Top cover (see Top cover on page 65)
When replacing the system board, be sure to remove the following components from the defective system board and install on the replacement system board:
●SIM (see SIM on page 48)
●Memory module (see Memory modules on page 54)
●WLAN module (see WLAN/Bluetooth combo card on page 58)
●WWAN module (see WWAN module on page 56)
●Modem module (see Modem module on page 76)
●Processor (see Processor on page 97)
Remove the system board:
1.Position the computer upright with the front toward you.
86 Chapter 4 Removal and replacement procedures