Re: wiring up a 3 way switch
Although there are multiple wiring paths that can be involved there is only one way to wire 3-way switches. Each switch has 3 terminal screws 1 on one end and two on the other. The two screw end is where the travelers are connected that go between the two switches. The one screw end has the power connected on one switch and the load (light) on the other switch. With only a 3 conductor wire in each boxes and if it was wired properly to begin with, in both boxes the black wire should go on the single screw and the white and red on the other two screws (travelers). It makes no difference which side you put th white or red.
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