I would like to install a wifi switch for my outdoor low voltage landscape lighting. There was a timer switch there but it went out. There is one hot (black), one neutral (white) and one ground in the box. The KASA smart switch I bought has 2 black connections (Line/Load). When I tied them all together, the lights were very dim and my research led me to learn I can't connect the live/load wires.

Any suggestions on how I can install a smart switch without a live and a load wire in the junction box?

TIA.

Does the white wire have any black marks or tape on it? If so, it could also be a hot line.

You need a transformer 120v to 12v. You can wire the switch to an outlet and then plug the transformer into the outlet. Most people find it easier to get a transformer with a time already built in, but that doesn't accomplish your goal.

Does your transformer plug into a normal 120v outlet? I plug in my transformer into this plug and just use the smart functionality of the plug.

https://www.amazon.com/gp/product/B091FXH2FR/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

I have a transformer down the line from the switch to power the low voltage. This switch is in my garage to feed power to the transformer. We had it on a timer before but the screen went out on it and so I couldn't re-program. I should have taken a picture of how it was wired, but I didn't. It wasn't a smart switch. Maybe I should look for one of those?

Thanks for any thoughts.

A pic might help. How old is your house? My guess is that white one might not be a neutral. You should have line, load, neutral, and ground.

As mentioned above, some pics would help.

I think what you're dealing with is something like below. Instead of running a cable from the power supply to the light switch and another cable back, electricians used to sometimes run one cable and use the black conductor for supply hot, the white conductor for switched hot. No need for a neutral with traditional light switches, but a modern smart switch requires a neutral for control power.



There's a few ways to confirm this, but if you can figure out which electrical box upstream is supplying this switch, you'll probably see a white tied into a black. They do make 'no-neutral' smart switches for exactly this type of setup but I don't know how well they work. It also may be easier just to install a smart outlet where the transformer is plugged in and abandon the switch altogether (ETA - already mentioned above).

Thanks all. I will take some pictures this afternoon. The house was built in 2017.

If I understand correctly your switch looks similar to this except you have a two blacks instead of one black one red. And you tried to wire all the blacks to one wire nut instead of like this?

I believe Kasa makes smart switches for set ups without a neutral.

Here are photos of what I am working with. Thank you all again for any thoughts!

That cap with red on the white wire coming out of the switch could mean it is a hot line. Do you have a multimeter or tester or anything to see if the black or white wires have a voltage coming into them?

Also, I'm more curious about the outlet the low voltage transformer is plugged into. That outlet is probably connected to your switch in the way BenTheGoodAg drew above.

Yeah, I agree that outdoor outlet is likely where that switch loop ties in. I'd bet the wirenuts are just there from when OP removed the timer, though.

It's interesting that the timer box is an 'old work' box on a 2017 build. Someone added it after the fact. It'd be easy to loosen those two screws, pull the box out and see where the wires run off to. Because it is 'old work' may even be easy to pull a replacement cable with an extra conductor (hot (black), switched hot (red), neutral (white), and ground.)

You need to confirm that switch loop is wired how we think it is (slight variation of the sketch above), and it gives you a few options:
- Replace the cable with an extra conductor cable (12/3 Romex).
- Use a 'No Neutral' smart switch. - Probably the easiest option.
- Bond the black and white conductors in the timer box, and replace the outdoor outlet with a smart outlet. Blank faceplate on the timer box. Add a label inside the box if you do this so someone in the future knows what this is.
- Disconnect the switch loop in the outlet box and replace the outlet with a smart outlet (better option than above).

Thanks for all of the input. As for the wire nut, yes, I just put it on there when I removed the old timer. I tried wiring in the "no neutral wire required" switch this morning as though the white wire was a load or line and not a neutral, but I guess I need some sort of wifi bridge that I don't have. The switch didn't seem to work though even with just pushing the on/off on the actual switch. I"m going to call an electrician. Thanks again for the help!

Update -

I pulled the box out and saw that the white wire in the box was, as you guys assumed, a hot wire running to the breaker, and the black wire was running to the outlet, so there was no neutral. I ordered the bridge for the no neutral switch and got it all hooked up last night.

Thanks for all of the help!