Quick answer
An AFCI (Arc Fault Circuit Interrupter) breaker trips to prevent electrical fires. To reset, turn it fully off then on. If it trips again, disconnect devices on the circuit and test each one.
Confirm the symptom
- Breaker labeled "AFCI" trips frequently
- Power cuts to one or more outlets or lights
- Breaker won't reset or resets then trips immediately
Tools and prep
- Voltage tester
- Screwdriver (flathead or Phillips, depending on breaker box)
- Flashlight
- Pen and paper to note circuit layout
- Turn off power at the main breaker before working inside the panel
Step-by-step troubleshooting
- Step 1: Turn Off the AFCI BreakerDo: Flip the AFCI breaker to the OFF position.Observe: Breaker moves to OFF.Means: Breaker is now de-energized.Next: Step 2: Turn Breaker Back On
- Step 2: Turn Breaker Back OnDo: Move the breaker to the ON position.Observe: Breaker stays on without tripping.Means: Issue may be resolved temporarily.Next: Step 3: Monitor for Tripping
- Step 3: Monitor for TrippingDo: Use the circuit normally for 1–2 hours.Observe: Breaker remains on.Means: No immediate fault detected.Next: Step 4: Identify the Cause if Tripping Recurs
- Step 4: Identify the Cause if Tripping RecursDo: Turn off the breaker and unplug all devices on the circuit.Observe: Breaker stays off.Means: Prepares for testing individual devices.Next: Step 5: Test Devices and Outlets
- Step 5: Test Devices and OutletsDo: Plug in devices one at a time and turn the breaker on after each.Observe: Breaker trips after plugging in a specific device.Means: Faulty device or wiring is causing the trip.Next: Step 6: Inspect Wiring and Outlets
- Step 6: Inspect Wiring and OutletsDo: Check outlets and wiring for damage, loose connections, or frayed cords.Observe: Visible damage or loose wires found.Means: Damaged wiring or outlets are likely the cause.Next: Step 7: Replace or Repair Faulty Components
- Step 7: Replace or Repair Faulty ComponentsDo: Replace damaged outlets or cords, or tighten loose connections.Observe: No visible damage and connections are secure.Means: Circuit should now operate safely.Next: Step 8: Test the Circuit Again
- Step 8: Test the Circuit AgainDo: Turn the breaker on and use the circuit normally.Observe: Breaker stays on without tripping.Means: Issue is resolved.Next: Done
Common causes
| Cause | Likelihood | Difficulty | Part often needed |
|---|---|---|---|
| Faulty appliance or device Arcing inside the device triggers the AFCI. | Common | Easy | Appliance repair or replacement |
| Loose or damaged outlet wiring Loose connections create arcs that AFCI detects. | Common | Easy–Medium | Outlet or wiring replacement |
| Damaged AFCI breaker Internal failure causes false trips or inability to reset. | Sometimes | Medium | AFCI breaker replacement |
| Overloaded circuit Excessive current draw can cause arcing. | Sometimes | Easy | None, if load is reduced |
| Moisture in outlets or wiring Water conducts electricity and causes arcs. | Rare | Medium | Outlet or wiring replacement |
| Old or deteriorated wiring Aging insulation can crack and cause arcs. | Rare | Hard | Wiring replacement |
Parts matching
Common parts needed for AFCI breaker issues:
- AFCI circuit breaker (match amperage and type to panel)
- Outlet or receptacle (if wiring is damaged)
- Voltage tester
- Wire nuts and electrical tape
- Replacement cords for damaged appliances
Always match the amperage and type of the original AFCI breaker when replacing it.
When to call a professional
- Breaker trips repeatedly after testing all devices and outlets
- You find damaged or deteriorated wiring in walls
- The AFCI breaker won't reset at all
- You're unsure about working inside the electrical panel
- You smell burning or see visible damage in the panel
FAQ
What does an AFCI breaker do?
An AFCI breaker detects dangerous electrical arcs and interrupts the circuit to prevent fires.
Can I replace an AFCI breaker myself?
Yes, if you're experienced with electrical panels and follow safety steps. Otherwise, call a professional.
Why does my AFCI breaker trip even with no devices plugged in?
This may indicate a wiring issue in the circuit, such as a loose connection or damaged insulation.
How do I know if the AFCI breaker is faulty?
If it trips without cause or won't reset, it may be faulty and need replacement.
Can a GFCI outlet cause an AFCI breaker to trip?
Yes, if the GFCI outlet is faulty or wired incorrectly, it can cause an AFCI breaker to trip.