Port problem? Mindstorms EV3 brick doesn't detect sensor blocks
Welcome Violetta. The EV3 Brick has a total of 8 ports - 4 output ports on one side labeled A-D, used for driving motors, and 4 input ports on the other side of the brick labeled 1-4, used for getting information from sensors.



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Make sure you have plugged your sensors into the correct port, as plugging them into ports A-D will not allow the Brick to detect them.