Ceiling light junction box has 2 wires (black and white on both). One of the two is hot (always juiced). The other of the two travels down the wall to the switch junction box, and this is the only wire in this junction box. When I connect the two blacks and the two whites of the ceiling junction box, the switch wires become juiced. But when I try to hook up a switch to those switch wires, the switch doesn't cut the power to the ceiling junction box when I flip the switch on and off. Why?? -very frustrated.
You wired it wrong. Disconnect all of the wires, take a piece of black tape and put it on the white wire that goes to the switch. Connect the other white wire to white of the fixture. Connect the black from the switch to the fixture, Connect the grounds, then connect the last 2 wires together. Now it should work.
You need 2 wires going to the switch. You have the black wire from your power source on the bottom screw of the switch and another wire going to your fixture. They should both be black. If it is a white wire then paint it black at both ends. Connect the real black wire to the black on the fixture and the painted black wire to the black in the ceiling and connect both whites. You had nothing there to break the connection.
The light fixture junction box should not have an always hot wire in it. The switch box should have the always hot wire and a neutral wire. The switch may be wired wrong by being located on the neutral wire instead of the hot wire. Even if this were the case the light switch would still turn the light on and off so something else is also possibly wrong. You may have a system where the hot wire for the switch goes through the ceiling box(the magic word is through) to the switch box. You have to trace the hot wire backwards. Good luck!
You should check your building code in your area even though 12/2 is the most common allowed wire for homes some juridictions require 10/2 which is a larger gage wire. If you do not use what is code than if it causes a fire your insurance may not pay due to you usse a wire that is not up to code
black wires tied together, and white wires connected to the fixture, doesn't matter which wire is connected to switch. Your power is in the box itself not to the switch, so you need to open the circuit. think of it this way, if the wire was connected as one piece it would be hot on the switch and blow breaker if that switch was turned on. well imagine cutting the wire open exposing the black wire and white wire, if you snip the white wire the power is terminated. If you attached the snipped white wire to the fixure it would power up, resulting in the white wire coming from the switch to now be an extention of the black wire, you should tape this wire with a piece of electrical tape to indicate its hot for future reference.
