HP TC4400 - Manual (Page 137)

5–54 Maintenance and Service Guide
Removal and Replacement Procedures
2. Release the ZIF connector to which the infrared board cable
is connected and disconnect the cable 1 from the system
board.
3. Remove the Torx8 T8M2.0×5.0 screw 2 that secures the
infrared board to the system board.
4. Remove the infrared board 3.
Removing the Infrared Board
Reverse the above procedure to install the infrared board.