I'm just trying to replace a broken dimmer switch, but can't make heads or tails out of the directions. Please see the photo of the partially attached NEW dimmer. Only the ground is connected so far.

The old switch was simply a vertical slider that turned the light off when it was slid down all the way... and made the light brighter by sliding it up.

The new dimmer is a combo rocker and little separate slider. I'm just not sure how to connect the rest. As you can see, sticking out from the wall are 2 blacks and 1 red. Remaining wires coming off the new dimmer are 2 reds and 1 black.

Could you please shed some light on this? (Note the bad electrical joke. :-)

Thank you!

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[2]: https://photos.app.goo.gl/PCAGXynuxuJYnVmPAenter image description hereenter image description hereenter image description here

  • Please post the model # of the new dimmer. With that, we should be able to look up the manufacturer's installation instructions and give a definitive answer regarding wire connections and other issues. Dec 19, 2018 at 14:39
  • Look at the 3 wires coming out of the box, black black red. On the old switch, were any of those wires tied together? Landing on the same terminal or wire nut? Also, is there a second switch somewhere else that can also control this light? Dec 19, 2018 at 17:48
  • Can you post a photo of the inside of the box for the light that was controlled by this dimmer? Dec 20, 2018 at 2:05
  • Hi Harper: I believe the 2 black wires were together. In the photo you also see 2 tan wires together in a wire nut. I think I just pulled them out from the back of the box to get a better photo. And yes, there is another switch that turns this same light on and off... It happens to not be a dimmer. Thanks so much. P
    – EricWood
    Dec 20, 2018 at 7:06
  • Hi ThreePhaseEel... The inside box photo is posted. Thanks so much.
    – EricWood
    Dec 20, 2018 at 7:08

1 Answer 1


There are 2 things I see from your photo and video.

First I believe the two black wires in the box are a source wire (120V) and a continuation of the source to another box. This means with both of them apart, something else in your dwelling is not working. So check that out. The red wire is probably the switch leg to your light or lighting fixtures.

Second it looks like the replacement dimmer you have is for a 3-way dimming set up. The 2 red wires are the carriers and the black goes to the light fixture.

If what I said is correct then you can connect the two black conductors in the box with a one red conductor on the dimmer and wire nut off the second red wire. Then you can connect the red conductor from the box to the black wire at the dimmer and that should work. You might just take it back and get the proper dimmer switch.

WARNING I can't be sure. Since I am not on site and cannot test the conductors in the box and cannot read the information on the dimmer. You might check the box the dimmer came in there is usually schematics on connecting the dimmer on the inside of the box. Also take a meter and identify the wires inside the wall junction box.

Good luck and be safe. Make sure your conductors are all turned of at the panel before trying any connections.

  • I disagree regarding the 3-way "you might just take it back and get the proper dimmer switch" statement. There are plenty of dimmers now like leviton.com/en/products/ddl06-1lz that are designed to handle both single-pole and 3-way switches because it is cheaper than making & stocking two different SKUs. I know the dimmer here is not the one I linked because the one I linked uses screws rather coming with pigtails. But it may be designed in essentially the same way. Or maybe not...need the model #. Dec 19, 2018 at 14:37
  • @manassehkatz - The problem is we don't know what kind of dimmer he has and I did give him an option on how to use a 3-way as a single pole. Dec 19, 2018 at 15:56
  • Agreed. My point is that it might be a model where the instructions tell you what to do to use it as a single pole. Admittedly, the manufacturer instructions are often confusing to non-technical people. But we can't interpret them for him without knowing the model! Dec 19, 2018 at 16:19
  • Thanks so much 4 all your responses so far. I am uploading 2 files, one showing the directions and the other the front cover of the direction booklet showing some specs. One of the reasons I was confused about this whole process was because step number three talks about identifying the type of circuit that you have, it talks about which wires connect to which color screws. These dimmer switches don't have screws on the back, because the switches are covered in a plastic case and the wires go through the plastic case. I hope this helps. I'll wait your responses before blowing myself up. Thanks!
    – EricWood
    Dec 19, 2018 at 17:37
  • I'm also adding an additional screenshot from the product listing page. Thank you.
    – EricWood
    Dec 19, 2018 at 17:48

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