Originally Posted by 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.
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?