Thanks for your help first.
I am trying to replace a dimmer switch (it has 2 black wires coming out from the switch). Then there are 4 wires from the J-Box (red, black, white, and ground). It was previously connected from 4 wires into an older 2 wires dimmer switch and I am going to replace the switch; however, I forgot how it was connected to the switch. I measured the volt (white, black =120V), (red, black =120V), (white, red=0V). I tried black red connect to switch (one wire) and white to the other wire and light just stays on even when OFF. It is not a 3way switch, is a single switch that connects to the light and was working before. Did I do something wrong?
I tried black red connect to switch (one wire) and white to the other wire and light just stays on even when OFF. Did I do something wrong?
I also tried black connects to one wire from the switch and red, white connect to the other wire but light is not on at all.
tried connect black to one wire (from switch) and red to other wire of switch (capped white) and also white to one wire, black to other wire and capped red, but no luck again, light won't go on.
That's what I think but I can't find the white wire from the light source from the electrical box. Inside the electrical box, only those 4 wires from the J-Box and that's all...so I connect red to one wire on the switch and black to the other of the switch, then ground to the screw and I have the white hanging