What's actually causing this
Light switches fail when the internal contacts wear out from repeated use. They can also fail from loose wire connections at the terminals, which create intermittent contact and heat.
What you'll need
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- Replacement light switch Shop →
- Non-contact voltage tester Shop →
- Phillips and flathead screwdrivers Shop →
- Wire stripper Shop →
Step-by-step fix
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1
Turn off the circuit
Go to the breaker panel and turn off the circuit controlling the switch. Verify it's off by flipping the switch — the light should not respond.
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2
Test for voltage
Remove the switch cover plate. Hold a non-contact voltage tester near the wires before touching anything. The tester should show no voltage.
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3
Remove the old switch
Unscrew the two mounting screws holding the switch to the electrical box. Gently pull the switch out. Take a photo of the wire connections before removing anything.
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4
Connect the new switch
Disconnect the wires from the old switch. Connect them to the new switch in the same configuration. For a single-pole switch: black wire to brass terminal, white wire to silver terminal, bare copper to green screw.
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5
Reinstall and test
Fold the wires back into the box and screw the switch in place. Restore power at the breaker. Test the switch.
Electricians in Boston typically charge $130–220/hr. Service calls and diagnostics typically run $150–400, while full circuit upgrades cost $2,000–5,000+.
Massachusetts requires licensed electrician. Homeowner exemptions do not apply. Boston requires permits and inspections.
Knob-and-tube wiring is common in pre-1950s homes and is uninsurable. Fuse boxes are common; breaker panel upgrades are frequent. Many older homes still have aluminum wiring. Electrical upgrades are common in renovations.
Boston faces significant severe weather risk — high winds, hail, and potential hurricane/tornado exposure can damage electrical panels, outdoor wiring, and service lines. Whole-house surge protection is strongly recommended.
DIY in Boston: Boston's strict code requirements, historic preservation rules, and high licensing standards make DIY repairs very restricted. Most homeowners must hire licensed professionals. Permits are expensive and inspections are thorough. The cost of non-compliance is high.
- You see burn marks or melted plastic on the switch or wires.
- There are more than 3 wires in the box — it may be a 3-way switch requiring different wiring.
- The switch controls multiple fixtures and you can't trace the wiring.
- The circuit breaker trips when you restore power.
Let Uncle AI diagnose it first.
Describe the problem. Uncle AI asks the right questions and tells you exactly what's broken — and whether you should fix it yourself or call someone in Boston.
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