Follow the procedures in Before Working Inside Your Computer:
Ensure that your work surface is flat and clean to prevent the computer cover from being scratched.
Turn off your computer.
If the computer is connected to a docking device (docked), undock it.
CAUTION: To disconnect a network cable, first unplug the cable from your computer and then unplug the cable from the network device.
Disconnect all network cables from the computer.
Disconnect your computer and all attached devices from their electrical outlets.
Close the display and turn the computer upside-down on a flat work surface.
Remove the main battery.
Turn the computer top-side up.
Open the display.
Press the power button to ground the system board.
Remove any installed ExpressCards or Smart Cards from the appropriate slots.
Removing the Optical-disk Drive Connector:
Disconnect the optical drive connector from the optical drive disk.
