Thread Tools
Old 06-23-2014, 09:35 PM
Guest
Join Date: Jun 2009
Posts: 1,311
Electricians: Help Me Troubleshoot Two 3-Way Switches

I have a question for you electricians. I have a hall light that has two 3-way switches. The light has been working for at least 20 years. About 7 years ago, I changed out the light fixture and replaced it with a fixture that had 3 halogen bulbs in it. The light and both switches have worked fine for the past 7 years.

When I say "worked fine", I mean, you could turn the light on or off at either switch without having to flip the other one. Turn it on upstairs, turn it off downstairs, and vice-versa.

About 2 weeks ago, we started having problems with that light fixture in that the switches stopped working.

I took both switches out of the wall, but left the wires connected, at first. From what I could tell, all the wires were seated correctly.

(Please note: All electrical work discussed below was done with the circuit breaker off.)

I started by replacing the downstairs switch because it looked like it had evidence of burning or a short. At the time, I did not realize that I had to make a note of the "common" black wire. However, I took a picture with my phone, and it looks like the other black wire and the red wire were twisted together. I replaced the switch with a new 3-way switch and put the single black wire into the common post and the other black wire and red wires onto the other posts.

I pushed both light switches back into the wall and tightened them down.

I tried the light but it didn't work, and when I flipped the switch upstairs, the lights flickered on and then off again. My thought was that the upstairs switch probably had a loose connection that got exacerbated when I shoved the switch back into the wall. (All wires were inserted into the pressure clips, as opposed to being screwed down.)

I then replaced the upstairs switch with a new 3-way switch. Now, however, I can only turn on the light when the upstairs switch is in one position and the downstairs switch is in the other.

So, here are my questions:

1. My thought is that I may not have put the true common black wire on the common post on one of the switches. Is it OK to open one of the switches and change the black wire?

2. If that doesn't work, what is my next troubleshooting step? Take out the light fixture and see if those wires are loose?

3. Is there an easy way to determine which wire in one switch is the same wire in the other switch? I have a multimeter but it doesn't have a continuity checker. I tried to hook a battery up to check the continuity by testing DC volts, but couldn't get a real good feeling I was doing the right thing. I'm afraid I just can picture the way the wires are connected in the wall.


Any words of wisdom?

Disclaimer: You are not my electrician. I am performing all work on my own house at my own risk. I make sure that the circuit breaker is turned off before doing anything with the light fixture or the switches. If I electrocute myself, it is my fault, not yours.

Thanks.
Old 06-23-2014, 10:12 PM
Guest
Join Date: Apr 2003
Location: Dayton Ohio USA
Posts: 26,958
not an electrician but there is a number of ways to wire a 3 way switch.
Old 06-23-2014, 10:19 PM
Guest
Join Date: Apr 2003
Location: Dayton Ohio USA
Posts: 26,958
I would think the first thing to establish is where power is brought in.
Old 06-23-2014, 11:25 PM
Guest
Join Date: Oct 2009
Location: CentralArkansas
Posts: 22,629
Is the OP sure the light fixture and bulbs are ok? The earlier problem may have burned them out.

You'll need a meter to check voltages. The earlier link has the various ways these circuits can be wired. You need to figure out which one is used in your house. Voltage checks can identify where the power comes from. Continuity checks can trace common connections. Always shut off power before attempting continuity checks.

Experienced electricians use a meter for continuity checks. A easier way is a continuity checker. if it lights open then you have continuity.
http://walmart.com/ip/GE-Light-U...ester/16561530

Last edited by aceplace57; 06-23-2014 at 11:30 PM.
Old 06-23-2014, 11:35 PM
Guest
Join Date: Oct 2009
Location: CentralArkansas
Posts: 22,629
Sorry, I had a typo. if the continuity checker lights up, then you've found two common wires. I prefer continuity checkers because they are quicker to use. It takes longer to read a meter. A meter is bigger/heavier to hold. I keep my continuity checker in my back pocket climbing ladders or up in the attic.

DIYers need to be very careful with meters. You have to check for voltage using live circuits. Make certain the meter is set for AC. You'll burn out the meter if it is set on the resistance range.

Last edited by aceplace57; 06-23-2014 at 11:39 PM.
Old 06-23-2014, 11:58 PM
Guest
Join Date: Oct 2009
Location: CentralArkansas
Posts: 22,629
I have a non contact voltage checker too. Quite useful to quickly find a hot wire.
http://all-spec.com/products/NCV...FTSVMgodNzMAWg

instructions/demo
http://youtube.com/watch?v=6F_wuU47PLU

another simple tester.
http://youtube.com/watch?v=D_eb37WApx8

Last edited by aceplace57; 06-24-2014 at 12:01 AM.
Old 06-24-2014, 04:49 AM
Guest
Join Date: Jan 2013
Location: Worcestershire UK
Posts: 5,549
Here is another link with some drawings.

http://how-to-wire-it.com/wiring...ay-switch.html
Old 06-24-2014, 08:15 AM
Guest
Join Date: Jun 2009
Posts: 1,311
Thanks for the help, all. I'll give the suggestions a try.

I know the light bulbs still work because the light fixture will come on in one configuration of switch settings. Tonight I will remove the light fixture and make sure all the connections are good and solid.
Old 06-24-2014, 09:35 AM
Charter Member
Join Date: Jun 2003
Location: Portlandia
Posts: 38,531
Quote:
I then replaced the upstairs switch with a new 3-way switch. Now, however, I can only turn on the light when the upstairs switch is in one position and the downstairs switch is in the other.
Sounds like you got your wires confused. Identify the feed wire from the panel. Connect it to the proper terminal on one switch. Identify the load wire going to the light fixture and connect it to the proper terminal on the other switch. That leaves the two traveler wires. Connect them to the other two screws on both switches. If there is still a switching problem, reverse the traveler wires on one of the switches. Should fix it.
Old 06-29-2014, 07:59 AM
Guest
Join Date: Jun 2009
Posts: 1,311
Problem Solved!

I found the problem: when I replaced the first switch, the common wire broke off at the terminal when I was shoving the switch back into the receptacle. Once I reattached it to the post, the light started working.

Thanks to all for the suggestions.
Old 06-29-2014, 08:36 PM
Guest
Join Date: Mar 2003
Location: Minneapolis, MN
Posts: 13,600
Quote:
Originally Posted by BobArrgh View Post
(All wires were inserted into the pressure clips, as opposed to being screwed down.)
P.S. Not a good idea. Using the screw terminals on the side of the switches is more secure over the long term.
Old 06-29-2014, 10:35 PM
Guest
Join Date: Jun 2009
Posts: 1,311
t-bonham, I should have said, "All wires had been originally inserted into the pressure clips ...". When I replaced the switches, I screwed the wires onto the posts.

Thanks again, all!
Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is Off
HTML code is Off

Forum Jump


All times are GMT -5. The time now is 06:26 AM.

Copyright © 2017
Best Topics: gun battleship commander eddington 100 won coin firehouse subs inches wool sweater shrinkage fax vs scan bi stands for parliament cigs hiring a scriptwriter microwave making noise dingy wall pepcid vs tums roommate vs housemate cat cowering christina ricci forehead kelly misfits accent franchise tag wiki repierce ears rotor resurfacing cost escorts stds removing caliper pins usernet pictures smoking with gum installing colonial charter pirate playlist trim eyelashes blocking mailbox unisom overdose death edinburgh scotland pronunciation coke ii bonsai apple heroclix scenario sherpa names holy zombie jesus big lots return policy no receipt how can you have your pudding if you don't eat your meat sir swears a lot get taste back when sick stop and shop commercials eyes blurry when i wake up how to withdraw money with account and routing number fast breathing while sleeping coed bathrooms in college death by a thousand cuts meaning bathroom vents into attic garden party lyrics meaning how long does it take for a cartilage piercing to close should i tell my girlfriend i love her louis ck no beard mom and dad making love how long after the sell by date is ground beef good does adam and eve have discreet shipping friends with benefits rules kissing friday the 13th chainsaw carmax early payoff penalty what do naturally red lips mean lowes pressure treated wood out of area private caller how far do squirrels travel otep shamaya real name k for strikeout origin definition of holocaust survivor does mail come earlier on saturdays where are these moths coming from christmas in the 70s memories