Faulty 3 way switch


  #1  
Old 09-02-16, 03:55 PM
G
Member
Thread Starter
Join Date: Sep 2016
Location: USA
Posts: 4
Upvotes: 0
Received 0 Upvotes on 0 Posts
Faulty 3 way switch

Just moved into a new town home (built 2004). The 3 way switch operating hall light upon entry from garage does not work properly (this was missed at inspection). The 1st switch (near entry door) does not turn on light in either position, regardless of position of 2nd switch (near front door). The 2nd switch does turn on lights in up position, regardless of position of 1st switch. If either switch is placed in 'middle' position, light does not work. In examining 1st switch box, there is a six wire cable...ground, 2 black (attached to two left hand terminals on switch), 1 red (attached to right hand terminal on switch), and 2 white (spliced together via wire nut). In examining 2nd switch, same situation as to which colored wires are attached to terminals. There are two other switches in this box. I didn't pull them out, and there is quite a bit of wiring in this box, so not quite sure of the details of what all is going in and out of this box. Hoping there's a simple solution (i.e., problem not 'in the walls'). Thanks.
 
  #2  
Old 09-02-16, 05:16 PM
ray2047's Avatar
Member
Join Date: Mar 2006
Location: USA
Posts: 29,711
Upvotes: 0
Received 15 Upvotes on 13 Posts
In examining 1st switch box, there is a six wire cable...ground, 2 black (attached to two left hand terminals on switch), 1 red (attached to right hand terminal on switch), and 2 white (spliced together via wire nut)
No 6-wire cable. If really cables probably a 2-conductor and a 3-conductor (grounds don't count). Sounds like you have a 2-conductor power in cable (or maybe to the light) and a 3-conductor cable between the switches. First thing is to verify if you have cables. If so disconnect the 2-conductor cable and measure between black and white. Do you get ~120v?

(Note testing must be done with a multimeter, preferably analog, or a test light, or a solenoid tester. You can't use a non contact tester.)

Next up we will try to sort out the other switch box.
 
  #3  
Old 09-02-16, 06:32 PM
PJmax's Avatar
Group Moderator
Join Date: Oct 2012
Location: Jersey
Posts: 62,091
Received 3,423 Upvotes on 3,069 Posts
Welcome to the forums.

Just to add to Ray's reply but don't want to muddy the water. If you have a two wire and a three wire cable at each ends....... the black wire from the two conductor cable needs to be on the common terminal at both switches.

Just FYI... there is no side or top or bottom to the screw terminals on a three way switch.
There are three screw terminals. Two are the travelers and are always the same color. Those two terminals are interchangeable. The third screw is always darker and is the common terminal. This is the important one.
 
  #4  
Old 09-04-16, 10:46 AM
G
Member
Thread Starter
Join Date: Sep 2016
Location: USA
Posts: 4
Upvotes: 0
Received 0 Upvotes on 0 Posts
Thanks

Thank you for the replies. We just moved in, and my circuit tester is packed away in a basement box. I'll dig it out, and then try some debugging.
 
  #5  
Old 09-04-16, 05:05 PM
ray2047's Avatar
Member
Join Date: Mar 2006
Location: USA
Posts: 29,711
Upvotes: 0
Received 15 Upvotes on 13 Posts
If your circuit tester is a non contact tester don't bother looking for it. It's too unreliable to be of any use.
 
  #6  
Old 09-12-16, 03:14 PM
G
Member
Thread Starter
Join Date: Sep 2016
Location: USA
Posts: 4
Upvotes: 0
Received 0 Upvotes on 0 Posts
OK, I found my circuit tester. It's a cheap Radio Shack digital, but seems to work OK (I have tested it on model train stuff). I also put the contact leads into a live outlet, and got a 120 volt reading. As you said on your first reply, there is a 2-conductor cable and a 3-conductor cable. I cut the power, and carefully sorted out the white and black wires from the 2-conductor cable, and freed from any connections. I turned the power back on, got a 0 reading from my tester. This was true regardless of the setting of the other wall switch (near front door, which does work to turn light off and on). Hope this helps. Thanks.
 
  #7  
Old 09-12-16, 04:06 PM
ray2047's Avatar
Member
Join Date: Mar 2006
Location: USA
Posts: 29,711
Upvotes: 0
Received 15 Upvotes on 13 Posts
Is the black of the 2-conductor cable connected to the common of the 3-way switch. Please ell us all the wiring at the other 3-way switch.
 
  #8  
Old 09-13-16, 10:25 AM
G
Member
Thread Starter
Join Date: Sep 2016
Location: USA
Posts: 4
Upvotes: 0
Received 0 Upvotes on 0 Posts
Yes, the black wire from the 2-conductor is connected to the common terminal (for switch near garage). Figuring out what is going on with the other switch is challenging, but here goes. There are three switches in the box...the 3 way in question, a 2 way for laundry fan, and 3 way for foyer light (other 2 switches work fine). There are six cables coming into the box....three 3-conductor and three 2-conductor. For one of the 3-conductors, the black wire goes to common terminal on the bad switch and the red wire goes to one of the other terminals on bad switch. The third terminal on this switch has a black wire, and comes from a splice....black wire to fan switch, black wire from a two conductor cable, and black wire from a three conductor cable (this three conductor seems to be 'extra'....not directly connected to either of the 3 way switches...). Five of the white wires are spliced together. The other white wire seems to be painted black after it comes out of the conductor a ways, and is connected to the foyer light 3 way switch. I realize I am not fully explaining the exact connections of all 15 wires coming into this box, but maybe there's enough info here to diagnose. If not, I can fully pull everything out and go deeper...just not sure if needed. Thanks.
 
 

Thread Tools
Search this Thread
 
Ask a Question
Question Title:
Description:
Your question will be posted in: