Home>Discussions>ELECTRICAL & LIGHTING>3 way light switch - light inop
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Kerry Alexander
Re: 3 way light switch - light inop

I am using a multimeter and checking voltage with one prong in the white wire and the other prong to the screws.
Thanks
I still don't know why I can't get power to switch 2.

JLMCDANIEL
Re: 3 way light switch - light inop

Just to be sure check power from the bare ground wire, you may have a bad connection or break in the neutral. Does nay of the wiring go through the light box? I believe the drawing below is what you should have. If you have power on all three screws of switch one then the power lead and the light lead are probably connected to a traveler screw rather than the screw marked as common and you are getting feed back. Are there any markings on the back of the switches?
Jack

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JLMCDANIEL
Re: 3 way light switch - light inop

Here's a thought. Disconnect the switch and set you meter to check continuity. You should read continuity between only two of the screws, flip the switch and check again. You will have continuity between only two screws . One of the screws will be in both pairs of positive continuity tests. That screw is "C". In other words if you read continuity between screw 1 and 3 with the switch in the up position and you read continuity between screw 2 and 3 with the switch down, screw 3 is "C" and that is the screw you want to connect power to on switch one and the screw you want to connect the black wire from the light on switch 2.
Jack

Kerry Alexander
Re: 3 way light switch - light inop

Reply to Jack,
The switch does have a common screw and that is where the black jumper connects. I had power using the ground.
I will check continuity in the morning.

JLMCDANIEL
Re: 3 way light switch - light inop

Be sure to check bothe switches. Also with the power off nut the red and black travelers together on one end then check and see if you have continuity between the red and black on the other end.
Jack

Kerry Alexander
Re: 3 way light switch - light inop

Jack, I just got back to check the continuity on my switches, and wires.
The switches are good. I have no continuity on my red or black travelers I checked from end to end of each wire.
Do I have a cut in the wire somewhere?
I had a new AC installed and the air handler is in the area of the light. The light did work after this install.
I am stumped but I have to figure this out.
Kerry

NEC
Re: 3 way light switch - light inop
Kerry Alexander wrote:

Jack, I just got back to check the continuity on my switches, and wires.
The switches are good. I have no continuity on my red or black travelers I checked from end to end of each wire.
Do I have a cut in the wire somewhere?
I had a new AC installed and the air handler is in the area of the light. The light did work after this install.
I am stumped but I have to figure this out.
Kerry

Yup, no magic pill here Kerry and time to go figure it out.

JLMCDANIEL
Re: 3 way light switch - light inop
Kerry Alexander wrote:

Jack, I just got back to check the continuity on my switches, and wires.
The switches are good. I have no continuity on my red or black travelers I checked from end to end of each wire.
Do I have a cut in the wire somewhere?
I had a new AC installed and the air handler is in the area of the light. The light did work after this install.
I am stumped but I have to figure this out.
Kerry

No continuity means you have an open. Could be cut cable, broken cable or cable pulled out of a mid way junction box. Could be the cable was stressed during AC install and finally broke.
Jack

Kerry Alexander
Re: 3 way light switch - light inop

I found two things wrong, a white wire had come loose and I found a third switch. Got it working now. Thanks for the help.
Guess I should have had a V8.
Kerry

JLMCDANIEL
Re: 3 way light switch - light inop

Thanks for reporting back Kerry, it's nice to know when a problem is solved and what the solutions was.
Jack

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