This is usually caused by a circuit overload (too many fixtures), a short circuit (a fault in the wiring or a fixture), or a ground fault. The first step is to unplug all devices on that circuit, reset the breaker, and then reconnect them one by one to identify the faulty . A light switch that does not work may look like a small problem, but it can sometimes point to a bigger issue. A switch may stop working because of loose wires, an old or broken part, or too much load on the circuit. When a light switch is going bad, the signs are often pretty easy to spot. When lights don't turn on at all, flicker or turn on and off on their own and changing light bulbs doesn't help the problem, it's a clear sign that something. Electrical troubleshooting often reveals several common wiring issues that can cause light switches to malfunction. The most common issue is a tripped circuit breaker.
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