Hello. I hope you're having a great day!
I have 3 switches in one electrical box. The first switch is for the back door light, the second switch is for a light above the garage and the third switch controls the back step lights. I purchased a digital timer and would prefer to use it for the back step lights; if not than my second choice would be to use it for the back door lights. I have a diagram of the current wiring and a schematic for the digital timer. How can I send you a copy of both so you can see clearly see what I am doing ? Thanks for your help.

Timer should have 2 blacks, possibly a black and a red, a white and a ground. Black is hot, should say line. /load, white is neutral and green is ground. You need a neutral for a digital timer to work. If both of the lights are switch looped and no neutral present, you won't be able to use a digital timer. Hot supply goes to line, light wire goes to load, white to neutral and green to ground.

What Brian is saying is that if you have only 3 cables, each with a black and white wire, you cannot use the timer because you need a neutral. If you have 4 cables each with a black and white wire you can use the the timer.

Describe the wiring in the switch box.

The source of the power to the switch is critical to know. If the source of the power to the switch is a switch loop (supply into the light box, then to the switch and back to the light box) then you may not be able to get this to work with the wiring you have.

Simple switches do not use a "Neutral" conductor. They only use the "Hot" conductor. Most often there is a white conductor (that is being used as a hot conductor) to feed the switch.

If the power is being fed to the switch and then to the lighting outlet, then you should have the neutral present in the switch box.

So, what type of wiring circuit do you have?

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