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Wireman · Lighting & switches troubleshooting · 2023 NEC ·

Lighting & switches

Flicker, dead fixtures, 3-way switches, dimmers.

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Lights flicker or dimOne fixture, one circuit or the whole house. Separates harmless from a failing neutral.Up to 3 steps Light won’t turn onA dead fixture on a plain switch. Work from the bulb to the switch to the fixture box.Up to 6 steps 3-way switches don’t work rightLight only works from one switch, or in some positions. Find the common and fix the travelers.Up to 3 steps 4-way switch problemsThree or more switches for one light. Keep each traveler pair on its own pair of screws.Up to 4 steps LED glows or flickers when offFaint glow or blinking with the switch off. Usually a lit switch, a smart control or induced voltage.Up to 4 steps Bulbs burn out quicklyOne fixture eating bulbs, or failures all over the building. Heat, vibration, sockets or high voltage.Up to 4 steps Dimmer buzzes, gets hot or won’t dimBuzzing, heat, flicker at low settings and LEDs that won’t dim smoothly.Up to 4 steps Recessed light shuts off and comes backA can light that goes out after a while, then comes back on. Usually its thermal protector doing its job.Up to 3 steps Fluorescent ballast or LED driver failureTubes dark, flickering or glowing at the ends, or an LED fixture that’s dead with power at it. Ballast, driver, lamp or socket.Up to 4 steps Motion sensor or photocell problemsLights on all day, never on at night, cycling, or a motion sensor that won’t trigger or won’t shut off.Up to 4 steps Ceiling fan won’t run, wobbles or remote failsDead fan, hum or missing speeds, a wobble, or a remote that quit. Supply, receiver, capacitor, switch or mounting.Up to 6 steps Smart switch won’t work (no neutral)Smart switch won’t power up, flickers the LEDs, or drops offline. Usually a missing neutral or the wrong one.Up to 3 steps Emergency or exit light fails its testUnit won’t light on the test button, dies before 90 minutes, shows no charge, or stays on with power on.Up to 2 steps Parking lot or pole light outOne pole dark, a whole row out, cycling at night or burning all day. Control, base fuses, underground or the head.Up to 3 steps