Porch light unpowered by separate multi-way switch

S_Jeff

An outdoor porch light (controlled by a standard single toggle light switch) will only work if the stairway lights are on. If the stairway lights are switched off, the porch light is completely unpowered. A pair of multi-way switches control the stairway lights.

A tenant recently discovered the problem and I am unsure whether it has been this way for a long time or is as result of a recent change to one of the stairway lights.

Why is this happening? How can I fix it?

I want to avoid calling an electrician if possible.

Thanks!

AllanJ

First you need to trace the wiring to find out whether the power (the power that is interrupted by the stairway light switches) go for the porch light es to the porch light switch first or to the porch light itself first.

Then you need to string a new cable from a power feed location not controlled by the stairway light switches over to the porch light or switch whichrever the power used to go in.

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joed

Is the porch light switch in the same box as one of the stairway switches? It could be a simple fix if it is.

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S_Jeff

Unfortunately, no. The nearest stairway switch is 15' from the porch light switch.

Techy

how many wires do you have in the porch light switch box

S_Jeff

I am not sure. I will be back at the property on Friday morning--Pacific time, with a voltmeter. I will inspect the switch and reply then.

Thanks.

SD515

This may be where you'll have to look also. If the outside light worked independantly from the stairs at one time, someone might have changed something incorrectly.

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Kyle

Just because you can, doesn't always mean you should

dmxtothemax

May be the light was installed by some dipstick,
Who did not know what he was doing!
Or didnt care!
Probably thought it was easier to just
hook up to the existing light.
Uses less wire.

S_Jeff

Here are some pics that illustrate the switch wiring:





The first is for the outdoor porch light, which has two black wires and a white wire that passes through in the back of the box.



The second is the dimmer/switch at the top of the stairs. The dimmer affects the porch light as well.




The third is the switch at the bottom of the stairs.

Can anyone tell, from this, why the porch light is being controlled by the stairway switches as well?

joed

We need to know which wire is the common on the three way switch in last picture.

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Julius793

In ur second picture there are three wires under one cap. My guess is one of the wires is feeding power to ur porch. So what I would do is open the splice and first connect one red to the blue, check if the porch light goes on. If it doesn't the connect the other red to the blue.

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joed

That would be my guess as well. The red coming from the bottom needs to be connected with the blue and black wires. Or maybe the blue and black need to be swap and the red connected to the two blacks.

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