Dell Latitude C540 - Manual (Page 103)

9.
If a modem is not already installed, go to step 11 . If you are replacing a modem, remove the existing
modem:
Remove the screw(s) securing the modem to the system board, and set them aside. a.
Pull straight up on the attached pull tab to lift the modem out of its connector on the system
board, and disconnect the modem cable. b.
10.
11.