Dell Inspiron 15 (3543, Early 2015) - Manual (Page 71)

2 Lift the connector latches and disconnect the display cable and I/O-
board cable from the system board.
3 Disconnect the power-adapter port cable and speaker cable from the
system board.
1 power-adapter port cable 2 display cable
3 tape 4 speaker cable
5 I/O-board cable 6 connector latch
4 Remove the screws that secure the system board to the computer base.
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