I have an outdoor light controlled by a pair of 3-way switches, A and B. The switch B is much closer to the light. Here are the behaviors I observe. During the day: A: Up B: Up or Down Light:ON A: Down B: Up Light:ON A: Down B: Down Light:OFF During the night: Light:ON (regardless) Also, believe that the light comes on at a certain hour. So it must be on a timer and not on a light sensor. However, I cannot locate the timer. The wiring on switch B is attached. I'm assuming I'm correct that the timer is involved. However, I still cannot make sense of the wiring and so I cannot figure out how to change it to make the three-way switches act normally during the day. [![enter image description here][1]][1] UPDATE: I've disconnected the wires and here's what discovered. The power comes via one of the 14/3 wires. The black is always hot. The red is hot during a few hours of the night (but not dusk to dawn. More like 1am-4am). Does this confirm that there's a timer somewhere along the way? What could it possibly look like? UPDATE: Mystery solved: [![enter image description here][2]][2] [1]: https://i.sstatic.net/HywwM.jpg [2]: https://i.sstatic.net/S3pa1.jpg