Janicholson posted this Oct29Jim or anyone plse explain.

[JMOR]

...the logic behind this and how it works to isolate one or the other.

Turn switch 1 up.
Turn switch 2 on and off. If it does go on and off, good
Next turn switch 1 down, then go to switch 2 and turn it on and off
If the light does not go off and on with it in one of those two tests it is the switch 1 that is bad
Doing it the opposite way tests Switch 2. Jim

 

[1948CaseVAI]

Not really sure what there is to explain about the procedure. If it is beyond you then it is dirt cheap to replace both switches and the whole job can be done in 5 minutes. You do want to check for any insulation on the wires that looks discolored as if it has been hot but chances are that one switch went bad (anything with moving parts is vunerable) and since they are cheap just replace them both.

 

[JMOR]

(quoted from post at 12:42:27 11/14/23) Not really sure what there is to explain about the procedure. If it is beyond you then it is dirt cheap to replace both switches and the whole job can be done in 5 minutes. You do want to check for any insulation on the wires that looks discolored as if it has been hot but chances are that one switch went bad (anything with moving parts is vunerable) and since they are cheap just replace them both.

hanks for replying, but all my 3-way switches are currently working just fine. I am just curious about the described procedure and how it works.

 

[Janicholson]

The failed 3 way switch (of the two switches) causes the light to not work when the opposing switch is in one of the two positions. Jim

 

[Butch(OH)]

I had this problem. I bought one switch.
replaced the one most used, didn't fix it.
Took the one I removed and replaced the
other one, fixed! And I didn't need a
degree to figure it out LOL

 

[wore out]

Bottom line is that if it was wired correctly and was working it's a switch issue and you can replace both for under $10 how much time do you want to waste mucking around?

 

[Butch(OH)]

So how is buying two and replacing both going to save time over buying one and removing and replacing both? Must be new age math??

 

[JMOR]

(quoted from post at 22:49:46 11/14/23) So how is buying two and replacing both going to save time over buying one and removing and replacing both? Must be new age math??

don't believe that diagnosis scheme works anyway.

 

[John T]

I would simply turn off all power DUH and use my ohm meter to check each switch and
replace whatever necessary. As always there's more than one way to skin a cat and to
each THEIR own methods and opinions.....

John T

 

[Hemmjo]

You really can not tell which switch is bad by flipping the switches. There is more that one way a circuit can fail. With multiple failure possibilities, the various if/then combinations do not always indicate the real problem. I cannot tell by flipping switches which is bad.

I made a sketch to try to visualize some of the possibilities. I do think it helps to visualize the issues.

 

[JMOR]

 

[Hemmjo]

That is correct. Too many possibilities to fit on one page. Just pull out
the switches and test them.

 

[sotxbill]

guess you could run across two defective switches???? so buying two would do.

 

[JMOR]

(quoted from post at 20:41:36 11/16/23) guess you could run across two defective switches???? so buying two would do.

enious!

 

[Jamisonj1]

(quoted from post at 09:42:27 11/14/23) Not really sure what there is to explain about the procedure. If it is beyond you then it is dirt cheap to replace both switches and the whole job can be done in 5 minutes. You do want to check for any insulation on the wires that looks discolored as if it has been hot but chances are that one switch went bad (anything with moving parts is vunerable) and since they are cheap just replace them both.

ell, it seems that it was smart mouth that it was "beyond you" to understand".

 

[JustIn Case]

(quoted from post at 11:28:37 11/14/23) ...the logic behind this and how it works to isolate one or the other.

Turn switch 1 up.
Turn switch 2 on and off. If it does go on and off, good
Next turn switch 1 down, then go to switch 2 and turn it on and off
If the light does not go off and on with it in one of those two tests it is the switch 1 that is bad
Doing it the opposite way tests Switch 2. Jim

I ve been around this sort of thing for 40+ years and yeh it probably be sorted out by logic, but it s just about easier and quicker to pull the switches out and check with a meter. But here s some additional food for thought. I never knew this arrangement even existed till about 3 years ago. I found it in the house we were living in. Great house we lived there and raised five kids there. All of the receptacle circuit had been retired using NM-B (Romeo). The breaker panel had been upgraded too. But some of the upstairs lighting circuit were still n
Knob and tube. 14 Ga wire on 15A breaker very lightly loaded but not very accessible. Anyway the three way circuit for the stairwell light used what I found to be a "California Three Way". Look it up, it s out there online. I have a feeling it comes from days of old where hot and neutral ran in knob and tube across attic and they didn t have to keep all of the wiring routed like we think of conventionally today. Look it up kind of interesting!

 

[JMOR]

(quoted from post at 14:55:36 11/19/23)

(quoted from post at 11:28:37 11/14/23) ...the logic behind this and how it works to isolate one or the other.

Turn switch 1 up.
Turn switch 2 on and off. If it does go on and off, good
Next turn switch 1 down, then go to switch 2 and turn it on and off
If the light does not go off and on with it in one of those two tests it is the switch 1 that is bad
Doing it the opposite way tests Switch 2. Jim

I ve been around this sort of thing for 40+ years and yeh it probably be sorted out by logic, but it s just about easier and quicker to pull the switches out and check with a meter. But here s some additional food for thought. I never knew this arrangement even existed till about 3 years ago. I found it in the house we were living in. Great house we lived there and raised five kids there. All of the receptacle circuit had been retired using NM-B (Romeo). The breaker panel had been upgraded too. But some of the upstairs lighting circuit were still n
Knob and tube. 14 Ga wire on 15A breaker very lightly loaded but not very accessible. Anyway the three way circuit for the stairwell light used what I found to be a "California Three Way". Look it up, it s out there online. I have a feeling it comes from days of old where hot and neutral ran in knob and tube across attic and they didn t have to keep all of the wiring routed like we think of conventionally today. Look it up kind of interesting!

amiliar with it. Not legal and could be deadly.. Shell and tip of bulb/socket can both be hot.

 

[Hemmjo]

I never head it called a california 3 way before. Buy my son and I had to remove all of the knob and tube wiring from an old house he bought. I could not figure out how that 3-way circuit worked. Did not have time to study it. Now, seeing the diagram is makes perfect sense.

It is very interesting, have to keep this in mind.

 

[JMOR]

(quoted from post at 09:01:35 11/20/23) I never head it called a california 3 way before. Buy my son and I had to remove all of the knob and tube wiring from an old house he bought. I could not figure out how that 3-way circuit worked. Did not have time to study it. Now, seeing the diagram is makes perfect sense.

It is very interesting, have to keep this in mind.

es, keep in mind...................not to use it!

 

[Hemmjo]

The shell of the socket is never hot.