I've got a couple switches controlling an exterior light which is not directly visible from either switch. That causes issues if, for instance, I am leaving during daylight hours and know I will be returning after dark and want to have the light on. I need to flip the switch and then check to see if the light is on (or check, then switch) which is inconvenient (there's a similar issue checking to turn if off during daylight hours).

Ideally, I'd like to use something like the Lutron dimmer system where tapping the top always turns it on and tapping the bottom always turns it off. I don't need a dimmer function so I'd rather not pay for one. Alternatively, switches that had an LED indicator to show when the circuit is energized would work. Are there any products available that would provide either feature? For various not-very good reasons, mostly having to do with laziness, I don't want to use a motion sensor or light sensor and just leave it "on" permanently.



  • Do Google search with "3 way switch with indicator light" and you will find numerous products that should meet your need. – Michael Karas Dec 8 '14 at 15:42
  • I probably should have stressed that the lighted indicator option was my least favorite. After looking at the prices for those switches, the dimmer route is only $10-20 more and doesn't offend my sensibilities (I really, really don't like switches in the "wrong" position). – Colin Young Dec 8 '14 at 16:03

Using a Z-Wave, Insteon or similar type of "smart" switch would be the simplest way, as just requires replacing the two existing switches. Expect $50-70 per switch. The is the closet thing I'm aware of that's an off-the-shelf solution to your problem.

You could also run a new wire between the two switches, to provide a switched return line that could power an indicator light. I don't know what the situation is like if it's feasible to run a line or worth the effort. Quick search finds some "3-way pilot light" switches that would work. Just to be clear, these require 4 conductors between the two 3-way switches rather than the usual 3.

You could also use a 120V panel-mount indicator light. You'd need to expand to a 2-gang box and custom mount the indicator in a blank faceplate.

Yet another option would be to build a current-sensing light circuit: basically, a current ring on the power line that is capable of sensing the light being on, and in turn, lights up a LED. This would require a custom circuit (though you can find lots of examples on the internet), a transformer to get the ~5VDC (or whatever you use for the circuit), and space to mount all of this stuff (you can't/shouldn't just mount a circuit board inside an enclosure that has 120V in it, it needs to be in a separate enclosure -- offhand I'm not sure if this is part of NEC, but if not it's just common sense).

  • Ouch. I can just grab a combo pack of dimmer and companion switch off the shelf for around $50 for both. Also, I don't have a Z-Wave or similar hub. And the other members of my household would not be pleased with the amount of tinkering I would end up doing with such a system ("How come the kitchen light switch is making the dining table light flash? It didn't do that yesterday."). – Colin Young Dec 8 '14 at 16:14
  • Yep, not cheap. But you don't need a hub, nor do you need to connect other lights/switches. – gregmac Dec 8 '14 at 17:53
  • But why would I want to buy smart-home compatible switches if I wasn't going to go all-in with a new toy to tinker with? :) – Colin Young Dec 8 '14 at 19:00

If you can add a wire then you can connect the final switched live back to the first switch for a total of 3 travelers, then you can connect the 3-ways like so:

enter image description here
(source wikipedia)

If terminal A is hot then the lamp is on. And on the other side terminal B is always hot and ready to power an indicator light.

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