Dell D15U001 Service Manual page 36

Steps
1. To remove the dummy metal bracket, insert a flat-head screwdriver in the hole of the bracket. Push the bracket to release
the bracket, and then lift the bracket out from the system.
2. Insert the optional I/O module into its slot from the inside of your computer.
3. Connect the I/O cable to the connector on the system board.
4. Replace the two (M3x3) screws that secure the optional I/O modules or two (M2x5) cross type screws that secure the
serial module to the computer chassis.
Next steps
1. Install the side cover.
2. Follow the procedure in
36 Removing and installing components
after working inside your computer.