Dell Inspiron 14 (M4040, Mid 2011) - Manual (Page 11)

Before You Begin 11
6 Disconnect all attached devices from your computer.
CAUTION: To help prevent damage to the system board, remove the main battery,
see "Removing the Battery" on page 13, before working inside the computer.
7 Remove the battery. See "Removing the Battery" on page 13.
8 Turn the computer top-side up, open the display, and press the power
button to ground the system board.