I am trying to change a regular switch to motion sensor switch.

Originally the switch had two blacks and one red connected. One of the blacks and the red are hot. One of the black was attached to a terminal labeled common on the old switch.

This is how the working/original connection look like enter image description here enter image description here

This is my attempt to connect it to the new switch. Where should the red be connected to. enter image description here

This is the new switch and wires. enter image description here

Edit: inside the box There are 3 cables that come in. one of them has the red in it in addition to black white and ground. The other two cables are regular Blk and white and ground. enter image description here Thanks.


2 Answers 2


If you want a motion sensor on this three-way switch circuit you will need a three-way capable motion sensor switch. They exist, though they are rarer to find and more expensive. Note that per instructions for at least Leviton and Lutron you will need to have a working ground, which I don't see in this box. You will also need to identify the wiring on the other switch in this circuit and modify the wiring on that switch. It's relatively complex so follow the instructions step-by-step.

Edit: per update from OP and review of the picture on a bigger screen there is totally a ground in this box. This means it would just be down to getting the right type of switch and carefully following the instructions.

  • Updated the post with what's in the box. I have grounds and whites. I have a balck hot and whites and ground if that's all needed for the switch. But I don't want to mess up the three way switch by not connecting the red.
    – Dawit
    Commented Dec 5, 2022 at 9:06
  • There are two bare wires in the back of the box. One each from the black jacketed cable on the left & the white jacketed cable on the right. They're tightly twisted and tucked at the back of the box. This is standard technique for grounding in US boxen. I don't see any white wire nuts. Otherwise, 100% and +1 anyway!
    – FreeMan
    Commented Dec 5, 2022 at 13:41
  • 1
    @FreeMan yes I was fooled by the NM jacket on my phone, looking at it again on desktop I finally track where the ground wire is headed. Looks like the box has everything needed once the right type of switch is obtained.
    – KMJ
    Commented Dec 5, 2022 at 15:48
  • Yet another win for the desktop/laptop PC vs mobile devices! :D
    – FreeMan
    Commented Dec 5, 2022 at 16:46

Normal (simple) switch has 2 wires, if it has 3 wires it is on 3 way circuit) (two switches in different location...your old switch is part of 3 way circuit,

The Leviton will need permanent Hot (black) and neutral (white) for its motion detection sensor.

Recommended wiring goes like this (from Leviton)


It is highly recommended to turn off the breaker while working unless you are killer voltage resistant :)

  • Looking the diagram closely it says to attach the green sleeved white to ground. That's part I didn't try yet.
    – Dawit
    Commented Dec 5, 2022 at 9:04
  • 1
    @Dawit as in my answer you're going to need a different model of switch to keep the 3-way functionality. Otherwise you'll end up with a motion sensor that works when the 3-way switch is in one position, and doesn't work when it's in the other position.
    – KMJ
    Commented Dec 5, 2022 at 15:51
  • ok thanks. getting 3way today and will try it out.
    – Dawit
    Commented Dec 5, 2022 at 20:10
  • @Dawit you can also skip (obandon) the 3 way if you do not need it any more
    – Traveler
    Commented Dec 5, 2022 at 20:25

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.