Problem with Security Light?

[williwatt]

I have a security light that just quit working and I can't figure out what happened to it. I have checked the light on another circuit and it works OK. When I check the wiring that comes through the soffit I am only getting a very low voltage reading -- in the 1-2 volts range. I checked the SPST switch that turns on the light and I get the same low voltage reading at the switch. I replaced the switch, but it didn't make any difference. I'm getting 120 volts at the breaker. Any ideas on what could be wrong with this circuit and what to do to fix it?

[Daryl]

I would guess you are using a digital meter, which will show a small voltage even when there is none. You can use a neon tester on the hot wire and verify that there is no voltage. You seem to have an open circuit. Perhaps there is a tripped gfci that you are not aware of.

[BobSch]

I'd start checking at the breaker. Make sure the screw holding the wire on the breaker is tight. After that it's a matter of tracing the wiring. Since most houses have multiple outlets or lights on the same circuit, you might find a loose wire nut in the box for another outlet before the switch. Check to see if you have any dead outlets in the house.

[gerti]

And always triple check that the volt meter is set to AC, and not to DC.

[williwatt]

Follow-up on Security Light problem

I have now checked the connection at the breaker box and there is 120 volts at the breaker. The power from that breaker goes to a triple wall switch. Two of the switches, one controls the porch light and one controls the foyer light, have power and are working, but the switch that controls the security light still does not have power even after changing out the switch. That circuit also provides power to the ceiling lights in the kitchen. I'm trying to figure out if there is a way to get power to the bad circuit from one of the switches that is working. What am I missing?

[smorris]

Just a thought, as I chased my tail over something similar once. Check to see if there is a GFI on the circuit somewhere. I had one trip at the other end of the house once that left me trying to figure out why an outdoor outlet quit working. Never did figure out what possessed the electrician to wire things that way.

[Mr__Bill]

Question: Is the power routed to the switch box and then to the lights or is the power to the lights with a switch leg down to the switch box?

If the power is to the switch box then you should see a black wire (hot in) that connects to all the switches and then a black that goes from the switch to the light. The common or white wire will also connect at the switch box and go to each light. If this is the case then the wire nut connection where the black wires connect together is the likely culprit. Turn off the breaker and remake that connection.

If the power goes to each light and a switch leg to the switch box then you should see a cable for each light with the black and white wire (may be red or a white wire painted or taped to be black) both connected to the switch. If this is the case then the problem is in the power feed to the light fixture and that is going to be a pain to trace back to find the loose connection or damaged wire.

Lets hope it's option one.
If it's option two you should look for other lights or outlets that do not work, and as stated before, for a GFCI in the link to the light switch.

Please note that these are not the only possible wiring options, only the two that I think are the most likely.

You might also let us know how old the house and wiring is and if at any time it was worked on by someone other than an electrician or yourself.

Bill
I'm not an electrician nor do I play one on TV, my opinions are based on limited knowledge and experience.

[williwatt]

Question: Is the power routed to the switch box and then to the lights or is the power to the lights with a switch leg down to the switch box?

If the power is to the switch box then you should see a black wire (hot in) that connects to all the switches and then a black that goes from the switch to the light. The common or white wire will also connect at the switch box and go to each light. If this is the case then the wire nut connection where the black wires connect together is the likely culprit. Turn off the breaker and remake that connection.

If the power goes to each light and a switch leg to the switch box then you should see a cable for each light with the black and white wire (may be red or a white wire painted or taped to be black) both connected to the switch. If this is the case then the problem is in the power feed to the light fixture and that is going to be a pain to trace back to find the loose connection or damaged wire.

Lets hope it's option one.
If it's option two you should look for other lights or outlets that do not work, and as stated before, for a GFCI in the link to the light switch.

Please note that these are not the only possible wiring options, only the two that I think are the most likely.

You might also let us know how old the house and wiring is and if at any time it was worked on by someone other than an electrician or yourself.

Bill
I'm not an electrician nor do I play one on TV, my opinions are based on limited knowledge and experience.

The two switches that are working have a black wire and a white wire to each terminal while the switch to the security light has a black wire to each terminal. Each black wire is from a different wire. The white wires from each wire are tied together with a crimped connector and the joint is covered with a vinyl insulator.

The house was built in 1960 and there have probably been some wiring changes, but the circuit with the problem appears to be original. There are no GFI devices any where in the house. The house is a split level and the three switches are in the foyer on the main floor. The security light is fed through the soffit on the upper level. The breaker box is in the basement so the wire feeds from there to the main floor, but I'm not sure how it gets to the upper level.

[Mr__Bill]

The two switches that are working have a black wire and a white wire to each terminal while the switch to the security light has a black wire to each terminal. Each black wire is from a different wire. The white wires from each wire are tied together with a crimped connector and the joint is covered with a vinyl insulator.

The house was built in 1960 and there have probably been some wiring changes, but the circuit with the problem appears to be original. There are no GFI devices any where in the house. The house is a split level and the three switches are in the foyer on the main floor. The security light is fed through the soffit on the upper level. The breaker box is in the basement so the wire feeds from there to the main floor, but I'm not sure how it gets to the upper level.

As the plot thickens....
Are you sure that only one breaker feeds the switches in the box?
Is there a switched hot and a common going out to the security light?
Where is the hot coming from for the security light?
Is it perhaps fed through another switch and only works when both are on?

It may help you to draw out the circuit and post it, perhaps someone with more knowledge than I can figure it out.

Another thought, have you done any work in the house, between when the light last worked and when you discovered the light not working? There may be a connection.

Bill

[williwatt]

When I attach my breaker finder on to the wires to the switch the light comes on when I attach to the white wire that is crimped and one of the black wires. After I turn the switch on then the light glows on either black wire because the circuit is closed. The switch is on the same breaker as the other two switches are.

I did have vinyl soffit installed, but all they did was take down the light and put it back. The light did work for 2-3 weeks after the soffit installation.

I am having a difficult time of trying to trace the circuit from the breaker box because it is hard to tell which wire it is because there is a wood cover around the breaker box.

[Daryl]

I think I would get up into the soffitt and check the wiring connections. Maybe they were in a hurry and made a connection that came loose.

[billwmeyer]

I think I would get up into the soffitt and check the wiring connections. Maybe they were in a hurry and made a connection that came loose.

I agree with Daryl. That is the first place I would look.
Bill

[Stytooner]

Dirt daubers love to fill wire nuts. They can do such a good job that it will loose a good connection. They are quick about it too. I would indeed check the light connections. It is a little more expensive, but any outside connections should be done with waterproof connectors regardless of location. That keeps bugs, humidity etc... out of the connection.

[williwatt]

The problem with getting into the soffit is that the installers used J-blocks to install the security lights and the inside part of the J-block is nailed in as is the J channel that is installed on the corner at a 45-degree angle. Also, the soffit is vented beadboard that is stiff and very difficult to remove and is held in place by a metal channel and the fascia cap. You can see the two wires from the circuit where I have removed the security light. If there is something loose or damaged, it must be in the attic or in some other part of the circuit. I won't be able to get into the attic until cooler weather.

[Stytooner]

This is why code require's all junctions in a box and be accessible. They broke code when they covered that up. There has to now be a junction that you cannot see.