Short answer
If one fixture flickers, it's usually the bulb, a dimmer that doesn't match LED bulbs, or a loose connection in that fixture or switch. If many lights flicker or dim together, suspect a loose connection at the panel or service, a heavy load on a shared circuit, or a problem on the utility side. Lights that get brighter while others dim can mean a failing neutral, which needs an electrician right away.
What's Probably Happening
Where the flicker happens, and what else is going on at the time, narrows it down fast. One light is a small problem. Many lights at once points upstream, toward the panel, the service, or the utility.
The Bulb or the Dimmer
LED bulbs are the most common flicker source in homes today. A bulb that isn't dimmable, or an older dimmer designed for incandescent bulbs, will often flicker or buzz at low settings. A cheap bulb nearing the end of its life can flicker too. Try a different bulb before anything else.
A Loose Connection at the Fixture or Switch
If the flicker changes when you tap the switch, or when a door closes, a connection in that switch box or fixture may be loose. Loose connections make heat. This is a repair for an electrician, not a reason to take the switch apart yourself.
Heavy Loads on a Shared Circuit
If lights dim when the microwave, a space heater, a well pump or a sump pump kicks on, those loads may share a circuit with the lighting, or the house may be near the limit of its service. A small, quick dip is common. A deep or lasting dip is not.
A Problem at the Panel or Service
When lights flicker all over the house, the cause is often a loose or corroded connection at the panel, the meter base or the service conductors. A failing neutral connection is the most serious version: some lights get brighter while others dim, and electronics may fail. That calls for an electrician right away.
The Utility Side
Wind, ice on lines, tree limbs and equipment problems on the street can all cause flicker, especially during Michigan storms. If neighbors see it too, it's likely the utility's to fix.
What You Can Safely Check Yourself
- Swap the bulb for a new one, ideally the same kind that works elsewhere in the house.
- If the light is on a dimmer, check that the bulbs are marked dimmable. Turn the dimmer all the way up and see whether the flicker stops.
- Note whether the flicker is one fixture, one room, or the whole house.
- Watch what's running when it happens: furnace, air conditioner, sump pump, well pump, microwave, washer.
- Ask a neighbor whether their lights are doing the same thing. If they are, call your utility.
- Touch the switch plate with the back of your hand. It can be slightly warm on a dimmer, but it should never be hot.
When to Stop and Call
- Some lights get brighter while others dim, or electronics are failing. That can be a lost neutral. Turn off sensitive equipment and call.
- Flicker happens across several rooms and isn't the utility.
- A switch, outlet or cover plate is hot, discolored or smells burnt. If there is smoke, get everyone out and call 911.
- Lights dim hard every time a big appliance starts, and it's getting worse.
- You see damage at the meter or the wires coming into the house. Stay back and call your utility (Consumers Energy at 1-800-477-5050, or Bay City Electric Light & Power inside Bay City).
Flicker that comes from the wiring doesn't fix itself. If the simple checks don't explain it, call Select Electric at (989) 835-3587 and tell us whether it's one light or the whole house, and what was running when you noticed it.
Common Questions
Is it normal for lights to dim when the furnace or air conditioner starts?
A brief, slight dip when a big motor starts is common, especially on older services. A dip you can clearly see, one that lasts, or one that is getting worse over time is worth having checked, because it can point to a loose connection or an undersized service.
Why do my LED bulbs flicker on a dimmer?
Many older dimmers were made for incandescent bulbs and don't work well with LEDs. Using bulbs marked dimmable and a dimmer rated for LED loads usually fixes it. If the flicker continues with matched parts, the switch or wiring may be the issue.
Could flickering be the utility's problem and not my house?
Yes. If neighbors see it too, or it happens during wind or storms, the cause may be on the utility side. Most of this area is served by Consumers Energy, and Bay City is served by Bay City Electric Light & Power. Call them for problems on their lines. Problems inside the house, including the service entrance and panel, are for an electrician.
Are flickering lights dangerous?
One bulb flickering usually isn't. Flickering across several rooms, lights that get brighter as others dim, or flicker paired with warm switches or a burning smell can mean a loose or failing connection, which can overheat. Those deserve a prompt look.