I am in a townhouse that was built in the late 70s. From what I can tell th e circut breakers, wiring, and electical switches are the original. I have been replacing my older style switches and sockets with modern square style swiches and sockets.
I removed a 3 way switch that was at the foot of my stairs and replaced it with a new one. When I turned the breaker back on I got power to other part s of the loop (my half bath on main floor) but no power to the three way sw itch.
I thought I may have put the black, white, or red wires in the wrong spots so I tried every possible combination. Each time the same result: nothing. Now the bedroom at the top of the stairs no longer has power either. This i s strange because the half bath still has power when the breaker is on, but not the light in the stairs or the bedroom at the top of stairs.
I have not changed anything on the 2nd floor yet. Only changed switches on the main floor.
Short of calling an electrician, I don't know what to do.