Why does the light fixture I installed no longer work? What happens if I connected the wrong wires.?

Question

This is an old house and both wires in the ceiling box were black with some white paint added to them and the same colored wire nuts. So there was no telling which one was the neutral and which was the live wire.

After I installed it, it worked at first, but the next day it no longer works. My electric tester shows that electricity is still flowing to the lights. Other items on that circuit are fine. The lightbulbs are fine. But it doesn't light up.

Did I probably just connect the wrong wires, or could there be some other cause? Could I have harmed the light fixture by connecting the wires incorrectly?

I just tried reversing the way the wires are connected, but no luck.

Either way they are connected, my electric tester beeps indicating that power is flowing through the fixture's wire and to the bulbs. So if it was a loose wire, the power wouldn't be getting to it right?

Answer 1

Could be something wrong with the fixture itself (it is defective) or the wires are lose -- I'm assuming that you used wire nuts for the connection, so twist them on tight.

If it worked initially, then you didn't hook it up wrong. Unless the watage or amperage on the fixture is wrong for that circuit (look at the old one), it has to be a defective fixture.

----edit----
Twist the bare end of the wires around each other (corkscrewise in a clockwise direction) before you twist the plastic wire nuts on -- make sure that you have a good connection.

Answer 2

In older houses the wire may be insulated with a rubber bound with woven cloth. Sometimes after many years the neutral or white wire blackens & takes a long hard look to recognise. I usually look for the one that is the "Least" black to find the neutral. The wire nuts aren't colour coded for polarity but for size instead, but the older ones are all black in colour. To find the "Line" wire use your tester, & with the circuit & wall switch on, carefully test between the metal box & each one of the wires. The "Line" or black wire will light up your tester.
I suspect you didn't quite grab one of your wires in the wire nut & after a day it popped out of the connection. So I recommend you take your fixture back down & re-do the connection after you have tested for the "Live" wire as described above. Before taking the fixture down make sure you have flipped off your circuit breaker, or taken out the fuse because you may have a bare wire floating around in behind the light. If both wires are black, then you will also want to wrap the one you have proven to be neutral with white electrical tape for future reference.

If you had miswired in such a way that would do permanent damage to the fixture then I would expect that the results would have been a little more instantaneous than the next day.

Answer 3

Sounds like a loose connection inside the light bulb screw-in fixture. Buy a new light bulb fixture.

Answer 4

When making connections using wire nuts, give them a good pull after you screw them onto the wires. Then you know you will have a solid connection. That's probably the reason.

Answer 5

doesn't really matter if the wires get hooked up backwards on a light... either u have a loose connection somewhere or u have bad bulbs.. not much to lights...
did u check for power at the wires or did u check at the light socket itself?
bulbs screwed in all the way?

Answer 6

Check out the plastic cap that you screw the wires together...the wire inside one of them has become loose....it never would have lighted up if the wires were crossed...you have it wired correctly..

Answer 7

Make sure that the connectins are GOOD...This is probably the problem that you are having