Now admitedly, it is not a straight wire, there is a blind (no access) junction box on a corner stud along this 10ft run (I know that because I put that junction box there myself when I remodeled the room 2 years ago). But still how could the connection inside the junction box fail?

Tsk-tsk! There's a good reason why it's against code to install a blind junction box and I'd wager dollars to donuts that it's precisely the cause of your problem.

Weak connections in junction boxes do fail. Yep, it really does happen. If it's been arcing slightly (something you might not know) one good motor surge could do it. Other times, expansion and contraction due to heat/cold variations can work a connection loose.

When outlets in a series stop working you go to the last working outlet to check the continuity of the wires. The problem will be there or in your blind junction box which you should open anyway and put a cover on.

Ain't no wire cut inside your wall - sure, it happens, but not much. 99% of electrical wiring problems will occur where the wires are spliced, and most of those are accessible, in an outlet or junction box. Buried splice? Heh heh, good luck finding it.

But I've a gut feeling there's something right under your nose, something that you just haven't seen yet. Take your time, and be methodical. You'll find it.

Do what hendricus said... look in the last working outlet on that circuit.

Thanks for the suggestions. I have been thinking that indeed it must be something under my nose because I cannot believe that I'm unlucky enough to have a non moving splice inside a junction box fail. I have tested it several times to no avail.

The last working receptacle is completely out and so are the two non working ones. I measure continuity from wire to wire and the white neutral wire has continuity from the last working receptacle to either one of the two non working ones. However the balck hot wire has no continuity from the last working receptacle to either one of the two non working receptacles.

So, now, perhaps, instead of ripping the wall (wallboard, plywood, vapor barrier, insulation), would it be out of the question to:

a) Forget about the wire that failed and disconnect it from the non functional receptacles
b) Tap into the ceiling light circuit and bring down from the attic, between the studs, a wire to the two receptacles

One issue I see with this solution is that the ceiling light circuit has a 15amp fuse as opposed to a 20amp for the receptacles. IÂm not sure though if there is any difference in wire gauge.

But assuming that the ceiling light circuit wire is capable of 20amps (say if I find out it is 12 AWG), can I then put the two failed receptacles on that circuit and change the fuse from 15 to 20amps?

Âor is mixing ceiling lights and receptacles another no-no.

Is there a GFCI that needs to be reset?????

Good point about GFCI, somewhere you hadn't thought about. Also, you testing with rcps removed and conductors spliced?

A bad splice in a buried junction-box is not out of the quesition. It happens. Look for a bulge in the wall, or evidence of recent patching.

Mixing receptacles and lighting on the same circuit is not a problem per se, but you certainly shouldn't change the fuse or breaker from 15 to 20 amps without being absolutely sure that all the wiring is 12 guage. Most of the time, a lighting circuit fused for 15 amps is wired with #14AWG which is not allow by code (and not safe) for a 20-amp circuit.

Depending on what else is on that circuit and what you intend to use those receptacles for, you can add a couple of 15-amp receptacles to a 15-amp light-and-receptacle circuit. (A lot of bedrooms are wired that way, BTW.) However, if there is a lot of lighting already on the circuit in terms of total wattage, that may or may not be a wise choice.

Is it really that hard to tear out and expose the presumably bad junction box? I dunno, but it seems to me that running new wires from the attic isn't all that trivial a job either.

Without knowing all of the hassles involved in this particular case, I'd be more inclined to fix the problem than circumvent it, but YMMV.

I agree with TT--I'm not much of a fan of workarounds, when there is a reasonable way to fix the problem correctly.

To address your original question, you can use a time-domain reflectometer (TDR) to determine the distance from the exposed end of the cable to the break. (However, rather few folks happen to have a TDR sitting around their home engineering lab...)

I suspect the break could also be found with an electrician's circuit tracer. The signal generator part of the tracer puts a tone on the cable, and if it has enough range, you should be able to trace along the wall with the receiver until you lose the signal. You may be able to hire an electrician to do this for you.

However, the break is in your buried junction box. Un-bury it, fix the break, and put a proper cover on it. Or better yet, replace the spliced line with one continuous line from one receptacle to the next, and get rid of the box entirely.

In the unlikely case that the problem isn't in the buried box, you haven't lost anything, because you need to fix the buried box anyway.

Suppose for a moment that the routing of the cable in the wall is actually different from what you presently assume. As a test, at the last working receptacle, disconnect the black wire and then test all other outlets- receptacles and lights. It might be that some outlet(s) that are in the string have not yet been identified.

simple solution is to open the wall at the junction and install an outlet there. i bet it fixes your broke wire as well.

The buried junction box needs to be addressed anyway. I am guessing the problem is in that box. Unless you were pounding nails or screws into the wall, the wire is not going to break. A connection will come apart. I have seen it before.

Have you considered moving?

:)

No, but my wife has :-)

bus_driver saidÂ
"Suppose for a moment that the routing of the cable in the wall is actually different from what you presently assumeÂ.Â.It might be that some outlet(s) that are in the string have not yet been identified."

This is a very good point, which I had not thought about.

So I removed the last working receptacle and 1st I tested continuity from the black wire of this last working receptacle to either one of the two non working ones, open circuit in both cases. Then I tested that everything else electrical in the house (lights and receptacles) is working in the house, and it did. So unfortunately the only explanation remains discountinuity somewhere inside the wall (probably the j-box).

Thanks for all your suggestions.

I will think about it for a week (just because I still find it hard to believe that the j-box in the wall failed) and then I will open the wall. Hopefully it will turn out to be the j-box, otherwise IÂm looking at potentially tearing up 10ft of wall.

BTW, I know where the hidden junction box is, because during remodeling two years ago I took a lot of pictures. I believe that from one of the pics I took I can now pinpoint where the junction box is to within +-1 inch. With some luck I may be able to make a hole no larger than the cover plate.

In retrospect, I did another blunder when I installed that hidden j-box. Not only did I leave the j-box hidden but since it was hidden, I did not bother to face the j-box so that its cover was towards the inner wall. I mounted the j-box with its cover facing sideways. So now I have to basically remove the j-box and put another one in  all this through a hole that is (hopefully) no bigger than the cover plate.

I will make sure to post the results once I fix it (or hit another puzzle along the way).

Well, after thinking about the problem for about 3 months in the background, I finally decided to act on it last weekend. The fix was successful. As many of you suggested, indeed, the wire connection inside the hidden junction box had come loose.

Luckily, I had taken quite a few pictures of the studs and the electrical wires when I demolished the walls to remodel the room last year, so I was able to locate where the junction box should be behind the wall by making some measurements on the digital pictures. In retrospect I was able to predict the location of the hidden J-Box from the digital photo with an accuracy of ½ inch! IÂll remember to always take pictures during remodels.

So I drilled one first hole where I thought the center of the box should have been and voila! I hit the box. Then I kept drilling holes close to each other until I located the perimeter of the box. Drilling the holes was made a little more complicated by the fact that this wall was sheathed with 3/4in plywood from the inside and there was also insulation between the plywood and the J-Box. So I had to drill through both the 5/8" wallboard and the 3/4" plywood. Once the exploratory holes revealed the perimeter of the box, I cut out the exact perimeter with a jigsaw.
Once I established access I broke the old hidden box (plastic) installed a new one, redid the wire connections and was able to cover the hole with a blank access plate. Having been careful while drilling the initial exploratory holes, the cutout was small enough that I was able to cover it with a standard size cover plate.

You got VERY lucky!!!

This is a classic example of why NOT to bury boxes, and to make sure splices are absolutely sound.