How to Troubleshoot a 3-Way Switch (Step-by-Step DIY)

Is your 3-way switch not working properly, or does one switch have to be in a certain position before the other one works? In this video, I’ll show you how to troubleshoot a 3-way switch, identify the wiring, and get both switches working properly again. I start with a common 3-way switch problem where one switch acts like a “master switch.” Then we take the switches apart and troubleshoot the circuit step by step. I’ll show you how to identify the incoming power/feed, determine which cable contains the travellers, identify the switch leg going to the light, and verify the traveller wires using continuity. Once we know what each conductor does, I’ll show you where they belong on the 3-way switches and test the finished circuit. In this video: How a 3-way switch circuit works How to troubleshoot a 3-way switch that isn’t working How to identify the incoming power/feed How to identify the traveller wires How to identify the switch leg How to test travellers for continuity How to identify the common terminal on a 3-way switch How to wire the switches correctly How to fix the “master switch” problem Always turn off power and verify that the circuit is de-energized before working on electrical wiring. If you are not comfortable identifying or testing electrical conductors, contact a qualified electrician. If this video helped you troubleshoot your 3-way switch, consider subscribing to Fix It With Fil for more electrical troubleshooting, wiring and DIY videos Electrical Safety Disclaimer: This video is for informational and educational purposes only. Electrical work can be dangerous. Always turn off and verify power, follow your local electrical codes, and only perform work you are legally permitted, qualified and comfortable to do. If you’re unsure, contact a licensed electrician.