Lighting, Light Fixtures, Ceiling and Exhaust Fans - 2 light switches for one light

On the bottom of the stairs going up to the bedrooms is a switch (switch "A") that turns on the ceiling light in the upstairs hall. At the top of the stairs is another switch for the same light (switch "B"). My problem is that if I flip on the light using switch "A" and then turn off the light using switch "B" I can't turn on the lights again from switch "A" (I would have to walk back upstairs and turn them on at the top).

Is there an easy fix for this?

You should have 2 3-way switches for the application you have. It sounds as if sombeody installed just SPST switches, or you may have a bad switch.

Look at the switches, if there a 3 terminals plus a ground terminal, they are 3 way switches. If this is the case, replacing the offending switch should take care of the probem.

If there are only two terminal plus the ground terminal, you have SPST switches so you have a master/ slave situation.

to correct the problem, you need to feed one of the switches with a hot wire, then run 2 travelers to the second swithc and the switch leg from that switch goes to the lights controlled.


Let us know waht you have. You need some more detail for the 3 way stuff but nobody should have installed this setup without 3 way switches so let's hope for the best and simply need to replace a switch.

"You should have 2 3-way switches for the application you have. It sounds as if sombeody installed just SPST switches, or you may have a bad switch.

Look at the switches, if there a 3 terminals plus a ground terminal, they are 3 way switches. If this is the case, replacing the offending switch should take care of the probem.

If there are only two terminal plus the ground terminal, you have SPST switches so you have a master/ slave situation.

to correct the problem, you need to feed one of the switches with a hot wire, then run 2 travelers to the second swithc and the switch leg from that switch goes to the lights controlled.

Let us know waht you have. You need some more detail for the 3 way stuff but nobody should have installed this setup without 3 way switches so let's hope for the best and simply need to replace a switch"


Thanks Nap,
the bottom switch is a 3 way but the top isn't, it just has 2 terminals and the ground. Sloution?

Do you have 12/3 with ground, or possibly 14/3 with ground, running from switch A to Switch B?

Here are some helpful photo diagrams:
http://www.californiaelectrician.net/kitchen/switches/3_way.html

These show 3-conductor cable between the two switches (red, black, white equals 3, PLUS ground makes four wires). This is a common configuration but there are other more complicated ones, for example where the hot wire goes to the ceiling box first.

You need to turn off the power and open each switch. Tell us all the wires and how they are connected. Make special note of the wire that is attached to the black screw. It could be also labeled as COMMON.