Tracing doorbell wires behind wall
The photo below is of my doorbell (with the cover removed) which has never worked since I bought this condo way back when. Half the doorbells in the building work, the other half don't work.
As you can see, the wires from or to the doorbell have been cut. I cannot tell where the wires connected to. I'm assuming they're supposed to connect to wires that are behind the wall.
Other than cutting up the wall, is there a tool that I can use that would allow me to locate the wires behind the wall (if they exist)?
I have a doorbell button at the front of the building on the first floor (my condo is on the 3rd floor).
I don't know where the transformer is. It could either be in the attic or basement. I have no idea how I'm going to find it.
The circuit breakers are in the basement.