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The video below shows a problem with a three-way switch, where two light switches control one light fixture. The switch in the hallway turns the light on and off, while the other switch in the dining room does nothing, depending on whether the hallway switch is in the on or off position.
The hallway switch is a single-pole switch with an “on” and “off” label. Turning to the on position completes a circuit, allowing electricity to flow to the light fixture.
The dining room switch, however, is a three-way switch that can be turned on or off without interrupting the circuit.
How To ID The Three-Way Switch
A three-way switch can be identified because it doesn’t have an “on” and “off” label. This is because the three-way switch has a common screw, which is always connected to the power source, and two “traveler” screws, which alternate which one is connected to the common screw depending on the position of the switch. In this case, the three-way switch may be up or down and be in the “on” position.
Here are the steps to diagnose and repair a three-way switch problem:
- Identify the two switches controlling the light fixture.
- Turn one switch on and off and observe if the light fixture turns on and off accordingly. Repeat with the other switch.
- If one switch does not control the light fixture, turn off the power to the circuit at the breaker box.
- Remove the switch plate and the switch from the electrical box.
- Identify the common screw, the traveler screws, and the ground wire. The common screw is usually black and is connected to a constant power source. The traveler screws are usually brass colored and are connected to the other three-way switch in the circuit.
- Inspect the wiring for a three-way switch according to the diagram. In most cases, the common wire should be connected to the common screw on the switch, and the traveler wires should be connected to the traveler screws.
- If the wiring is incorrect, swap the common and traveler wires.
Disclaimer: This blog post is for informational purposes only and should not be considered professional electrical advice. Working with electricity can be dangerous. Always consult with a qualified electrician before attempting any electrical work. The author and publisher of this blog post are not responsible for any injuries or damages that may occur as a result of following the information presented here.
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