Our house was built in 1941. When we had our inspection, the porch light worked just fine. Now it doesn't work at all. Yes, we have tried new bulbs. The strange thing is that there is a switch outside our door, which may be for an outdoor outlet, and a switch inside our door. We've tried various methods of switching one off, the other one, both on...but there is also a motion sensor thingamabob (technical term) outside near the light. Could this be the source of our problem? Any suggestions, aside from a costly electrician? Easy fixes we can do.
Anonymous2009-07-06T21:54:37Z
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Think of this as a fun little puzzle you can solve by the process of elimination. Buy a simple neon tester from Home Depot (about $2.95). It should be the kind with a little LED light in a plastic housing and 2 wires sticking out. This gadget will tell you which wire is "hot".
Test a light bulb in a lamp to be sure it is good, then place it in your porch light fixture.
Stick the leads of your tester into the outdoor outlet and see if it lights up. If so, try the switches to see if one turns off the power to that outlet. If not, try the switches to see if one turns on the power to the outlet. If one of the switches controls the outlet, then we can ignore it in our subsequent testing. (Unless we come up zero and have to return to it.)
First lets test the motion sensor which is the most likely suspect. Turn off the power. Remove the motion sensor and disconnect the two wires going to it. Short the wires together and tape them together with electrical tape temporarily.
Turn on the power and test every combination of your switches: both up; both down; outside up/inside down; inside up/ outside down.
If at any time the porch light comes on, the problem is with the motion sensor and you can either replace it or cap it off with the leads shorted together.
Second let's ensure the light fixture is not faulty.
Remove the light bulb from the fixture.
Turn off the power.
Remove the light fixture.
Tape the leads of your neon tester to the two leads formerly connected to the fixture. Turn the power back on and test the various switch positions as above. If the tester lights up in any of those switch positions, it is the fixture that is bad and needs to be re-wired or replaced.
If the problem has still not been revealed: let's test the switches.
Turn off the power.
Remove both switches from the boxes and disconnect the wires from the switches leaving the wires well separated and outside of the boxes.
Turn on the power.
Wearing snug latex or rubber gloves, hold the white wire of your tester against the metal box and , in turn, touch the black tester wire to each of the leads (that were on the switches). Eventually, one of the "touches" should produce light on your tester. That is the "hot" one;
Test all the other leads to ensure you don't have another "hot" lead.
(if the boxes housing the switches turn out to be plastic or non-metal, you have another problem; please post again)
Still wearing your gloves, short the "hot" wire to the other wire that was attached to the switch in that box. The porch light should come on. If it does, just install a new switch in that box.
If it does not, try shorting the two wires in the other switch box together, then try the two wires in the "hot" box.
By now, your problem should be resolved, but if not, you have the idea of systematically testing each component.
Have fun, but be careful. Electricity can give you a nasty burn. Wear your gloves and keep the power off while bare wires are exposed unless you are actually testing and on your highest "personal alert". Keep kids and other distractions away while you are working with live power.
At a guess the sensor has bit the dust. If you don't know anything about electricity I wouldn't go opening everything up. What jim said was the best. A volt stick looks kinda like a pen and will glow red and make a buzzing noise when its near something live.
Because the house is from 1941 you might get false readings however. Alot of old places are wired "loop at the light". That means at all times there will be a live wire at the light, its just not plugged into the light.
Even with the switch turned off there can still be a live at the light. So be careful.
For quick and fairly safe trouble shooting, get an inductive probe. This is a non contact tracer that will indicate AC power from about 50 to 600 volts. Most house wiring is 120 volts to ground/neutral. Test the switches by removing the face plate and using the probe in the box. The probe is non conductive and is only good for telling you there is power to the switch. This can also be used to test for power at the motion sensor and the lamp holder. If you have power at these locations, then the lamp, the switch or the motion detector may be faulty. Using an analog voltage tester, check for power through each component. I suspect that the motion detector may be the problem since many of them also contain a photo cell that can die suddenly, or it may be pointed at another light source, like a street light or the headlights of a car. To check for this, cover the photo cell with black paper for 10 minutes or so. If all of this fails to solve the problem, I suspect you will need a qualified professional electrician to do the trouble shooting. If you have power through all of the components, then check for an open neutral/ broken white wire in the system.
When you switch the switch on the outside, does it affect the light? If so you may have a case where you could swtch both off.
You get a volt meter and they are fairly cheap and you can check to see if the electric is going through the light by toucing one each to the wires coming in.
No., if you really don't know what you are doing, you may be better seeing if you have a handly neighbor who knows anything about electrical and having them theck it. You could turn off your electric and repalce the fixture. That is not too expensive. If you find that is not the problem, you could take it back to the store unless you like it better. You can make sure the wires are all inside one of the little caps so it can't short by one wire touching another.
When it comes to the 2 switches, if you can't figure them out so it is one and you can work it from the inside, I'd get an eelectrician to take off the outside one or to run it differently. If you want the plug outside to work, you simply could turn on the inside light.
The motion detector (could it be a sensor for light and dark and only come on at dark rather than motion detector? So if you go out there in daytime, it might not work but might at night? Try to turn it on at night.
You could remove the detector to check out whether it could be the problem. If it works without the detector on there, then it is faulty. If it still doesn't work either way, then there is another problem.
Basically you need to find out if the switch works. I'd change the switch as that is easy and costs maybe 49 cents to $1.50 - no biggie. It could be the switch. My mother went without a light in her bedroom for years and years until the day, I as an adult, asked her if she had the switch checked. She hadn't. I got a switch and turned off all the electric (over her reluctance for fear of electric) even though I turned off the main breaker and I changed the switch and voila, there was light from her ceiling unit. It was that simple, just the little switch had to be replaced. I'd problably change the switch first as that is the easiest to remedy and you are out the least money. I don't do a lot of electrical, but I've changed switches, outlets, put in phone wire, and wired a lamp and installed a ceiling fan. That is it. I'm also a woman. And I was in my early 20's when I changed my mom's light switch. I'm old now.
The motion detector should be getting power from somewhere.. If it isn't, then that could be the problem. In addition to throwing the switches in different order, you also have to go wave your hand in front of the motion detector!!
Get a volt-meter and start checking everything.
I'd try to trace those switches and see where they go. Good luck it's all part of the fun of older homes!