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Carefully lift the upper case about half of an inch and move it so that you can access the power and speaker cables.

If the upper case is sticking, it may be necessary to free the tabs holding the upper case to the metal framework along the outer edge of the battery compartment.

The connectors at the ends of the cables are attached very firmly to the sockets on the logic board. Pulling directly on the cable will either separate the cable from its connector or the socket from the logic board.

Lift the upper case enough to disconnect the blue and white power cable from the logic board. Using your fingernails or a dental pick, carefully pry the connector from its socket. Make sure you're pulling only on the connector and not on the socket.