Shop Products
Houzz Logo Print
lipper2000

Strange electrical light switch problem

lipper2000
9 years ago

Hello,

I moved into a house a bit over a year ago. I'm having an issue with a light switch that controls the lights outside of my garage. It looks to be a three way switch although there is not another switch in the garage or outside that is connected to this one at all. As you can see by the picture of it and also by the schematic I've drawn out, there is a connection on each screw of the switch.

There is another switch in this box that is exactly the same that controls the lights inside the garage. This is working fine. The is another switch inside the garage for the inside lights of the garage and these two switches act like a three way switch.

The breaker that feeds this box feeds these two switches and also plugs for garage door openers.

The other night the switch just stopped turning the outdoor lights on. I have tested the lights and they are fine in another receptacle.
The outdoor switch internal light stays on all the time regardless of which way you toggle the switch.

Inside the box, there are 4 cables coming to it. I have shown the dark wire inside the cables to be black, the white wire is white and the red wire I have "striped". I have also measured the AC voltage on each of these wires and there is only 120V on one of the cables. I measured the voltage after unscrewing every wire and taking off the marrets and connections. The earth gnds were left(they are not shown on the picture). I have shown the voltages measured in the picture. The "dots" in the picture are marrets.

I have tested another switch and have the same results(lights outside do not come on and the light on the switch itself stays on all the time).

I cannot make heads or tails of what the electrician has done here. I'm hoping one of you could lend me some assistance.

Thanks!

Drawing of wiring in light switch box
http://i.imgur.com/wfaGfEe.jpg

Picture of the switch that controls the outdoor lights that is giving me grief
http://i.imgur.com/ev6hntO.jpg

Comments (5)