Common Light Switch Wiring Problems : Electrical Online The problems can present themselves in a number of different ways, and resolving the problem is obviously very specific to each situation. In this post I review three common light switch wiring problems, how to troubleshoot the actual cause of the wiring problem, and how to resolve it. Why Light Switches May Not Be Working - Ask the Electrician Three Way Switch Wiring. Key Factor of Typical Light Switch Wiring: Light switches switch the power side of the circuit, not the neutral. Remember that white wires may not always be a neutral wire, especially if you see a white wire that is connected to a light switch. Use a voltage tester to verify the circuit wiring configurations.