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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.