I have a very weird setup for my living room, and at first I didn't actually realize what was happening until I started looking into replacing a 3-way switch with a 3-way smart dimmer (Leviton DZ6HD as the main dimmer and DD00R-DLZ as a remote dimmer).

I have two 3-way light switches that control a ceiling fan light. I also have a third switch next to one of the three way switches that controls power to the fan. The fan has a remote, and on the fan remote is a light switch button. I thought that the light switch button on the remote just didn't work, but then I realized something weirder was going on.

The remote only works to turn the fan and off when the single-pole fan switch is on. The two 3-way light switches seem to have no control of the fan.

I drew a diagram to show how each light was wired. After drawing this I realized some cables have cords that go directly to two separate light switches, which also seems odd to me (although I'm not an electrician). I have not taken the wires out of the switch to test which ones are hot or not.

Wiring for 3-way switch and unrelated light switch

Wiring for 3-way switch and single-pole fan switch

I also took pictures of the backs of the light switches, which I won't embed but I will link to.
Editor note: embedding makes it easier for everyone

A (3-Way for Light)

B (Light and Fan Switch)

C (3-Way for Light)

When the two 3-way light switches (A and C) are giving power to the ceiling fan light, the light is on and the "toggle light" button on the remote does nothing regardless of what position the ceiling fan switch (B) is in.

When the two 3-way light switches (A and C) are not giving power to the ceiling fan light, and the ceiling fan switch (B) is off, then the light is off and the "toggle light" button on the remote does nothing.

However, when the two 3-way light switches (A and C) are not giving power to the ceiling fan light, but the ceiling fan switch (B) is on, then and only then does the remote actually toggle the ceiling fan light.

So it seems to me that the two 3-way light switches (A and C) are wired directly to the light, while the fan switch (B) is wired to the fan receiver, which is also wired directly to the light.

I haven't looked at the wiring for the fan so I could be wrong, but nothing else really makes sense to me.

So my first question is, if this is right is that safe to have two sources of power go to one single light? Would that not provide too much power to the light?

My second question is, can I just replace the two 3-way switches with a smart 3-way dimmer switch and leave the single pole fan switch the way it is?

Edit to clarify: My goal here is to make the ceiling light be a smart dimmable light by installing a smart dimmer. Since the smart dimmers say specifically that they cannot control a fan, I am trying to replace both of the 3-way switches (A and C) with a 3 way smart dimmer switch (DZ6HD and DD00R).

  • Can you post photos of the insides of all boxes involved please? Also, how do you want things to work here? Sep 19, 2021 at 12:41
  • Yeah definitely, I just went ahead and mapped everything out. I updated my post with the diagrams and pictures. After looking at it all mapped out I am starting to think moreso that something is wired improperly here. As far as how I want things to work - the smart dimmers I have don't work for fans so I want the two smart dimmers to control the light. I am not as concerned about the fan, I would probably leave that one and just use the remote to turn the fan on and off.
    – scorgn
    Sep 19, 2021 at 22:35

1 Answer 1


The light switch wiring itself is straightforward

What you have for the two lightswitches is a straightforward 3-way setup with power entering and exiting at the same box. Installing the main smart dimmer in place of switch C and the remote in place of switch A shouldn't be a challenge, since you have separate hot wires for the fan and light running up from the main switch box.

However, your glitch is at the ceiling box

That said, the problem you're seeing with the extra power feed is because the light output from the fan remote receiver got wired in with the switched-hot for the lights, putting the two control sources in parallel with each other. This should be trivial to fix while you're in working on this; simply un-nut the receiver's light wire from the rest of the wires it's connected to and cap it off with its own wire nut.

  • Okay that makes sense, thanks. I was thinking that each cable was for a switch, but instead it's a line / load / traveler cable. So the instructions say to hook the main dimmer up like this i.imgur.com/oy8LsfX.png. Using the same image for the switch with my diagram, would I hook the purple, green, and blue highlighted cords on the left to the terminals as shown on the right of this picture i.imgur.com/ZP9hzQ1.png (with an added cable from the neutral bundle as highlighted orange)? Also, does it matter which traveler goes to which of the two terminals on the right?
    – scorgn
    Sep 20, 2021 at 3:41
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    @scorgn -- you'll have to retask the white in the inter-switch cable as a neutral and land black on the main dimmer's hot screw in addition to a pigtail from the existing hot wires in the box so that you have the correct wires available to you at the remote location, and fit the matching remote as well, of course Sep 21, 2021 at 0:39
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    @scorgn -- not quite, you need to have hot going to both the main dimmer and the remote, and there's only one communications bus wire coming back from the remote, not the pair of travelers that'd go with a mechanical 3-way switch Sep 21, 2021 at 11:37
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    Thanks for the patience. So I need to add a wire from the bundle of hots that red wire goes in, to the hot terminal on the main dimmer. Then attach the red to the hot terminal on the remote dimmer, so now both always have a live hot. Then the purple wire will go from the bundle of neutral wires to the neutral terminal of the remote. Then the green will go from the RD/YL of the remote to the RD/YL of the main. Then add a jumper from the bundle of neutral wires to the neutral terminal on the main. In the end it would look like this i.imgur.com/5cYdVVM.png. Does that sound right?
    – scorgn
    Sep 22, 2021 at 0:53
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    @scorgn -- you got it! Sep 22, 2021 at 1:57

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