I bought a Leviton timer and when I went to install it, I ran into a problem. The outlet box has ONLY three wires - Black, White and a bare copper ground. Looking at the wiring diagram for the Leviton timer, I don't know where the RD wire is supposed to be connected. I connected the Black from the box to the Black on the timer, and similarly White to White on the timer. When switched on, the timer lights up and I can hear a click but the outside light does not turn on. That's because the Red wire from the timer is not connected. Can someone please help me figure this out? I am replacing the currently installed timer with this Leviton one. But the previous timer had only 3 wires - black, white and ground. So I had no problem installing that previous one. Am attaching a pic to show my arrangement. enter image description here

  • except with the wrinkle of identifying colors. OP all due respect but if your first impulse is to match wires by color, I would get some more education on how to do this. While a house burndown is always a risk, the more immediate risk is wrecking equipment. Color means almost nothing -- or to be more precise, you often need to go cable-by-cable to research how this particular cable uses color. As things are, white is definitely not neutral, since you have a switch loop. You would need to test to determine which is always-hot and which is switched-hot. Feb 17 '18 at 18:33

Your timer needs requires four wires.

  • Black is "hot"
  • Red is the load wire, which is only hot when the switch is on (closed).
  • White is neutral, which allows the timer itself to use power to operate.
  • Bare/green is safety ground.

The box you're working at, does not have a neutral. It's what's called a "switch loop", so only has a hot, switched hot, and ground.

You'll either have to run new cable to this box, or buy a timer that doesn't require a neutral.

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