Customer Says An Outlet Doesn't Work, Translation To Fault Decision Tree

Why this matters

"The outlet doesn't work" is the highest-volume electrical complaint and the one most often fixed by the wrong person doing the wrong thing. Behind those four words sit a tripped GFCI somewhere upstream, a tripped breaker, a failed receptacle, a loose backstab connection that has gone open, an open neutral on the circuit, or a switch-controlled outlet the customer forgot about. Each has a distinct test signature. The discipline is to read the receptacle with a meter and a tester, work from the easy upstream causes (GFCI, breaker) toward the wiring, and identify whether the dead outlet has lost hot, lost neutral, or lost both. A senior tech clears the free causes in two minutes and reserves wall-opening for an actual open splice.

Symptom presentation

The customer reports one or more receptacles with no power: a phone charger does not charge, a lamp will not light. Useful variants: a single outlet dead while its neighbors work, a string of outlets dead together, an outlet that is dead only sometimes, or an outlet that quit after they ran a high-draw appliance (heater, hair dryer) which points to a heat-stressed connection or a tripped protective device. Note whether the dead outlet is in a kitchen, bath, garage, or outdoors, where it is almost certainly GFCI-protected.

Quick checks

• Plug in a known-good tester or lamp to confirm the outlet is truly dead, and check the neighbors to map the dead zone.
• Look for and reset any GFCI device on the circuit, including ones in other rooms (a single GFCI often protects a bath, the garage, and outdoor outlets downstream).
• Check the panel for a tripped or off branch breaker.
• See if the outlet is half-hot or switch-controlled (a wall switch may control it); flip nearby switches.
• With a meter at the receptacle: hot-to-neutral, hot-to-ground, neutral-to-ground. This tells you instantly what is missing.

Isolation tree

1. A GFCI is tripped upstream and resetting it restores the outlet? Done, but find why it tripped (moisture, a faulty load, or a ground fault) before leaving.
2. Branch breaker tripped or off? Reset and observe; if it re-trips, you have a circuit fault, not just a dead outlet. Pivot to a tripping-breaker diagnosis.
3. Meter reads 0 V hot-to-neutral and 0 V hot-to-ground, but 0 V neutral-to-ground? No hot reaching the outlet. The hot is open upstream: a loose feed-through connection at a prior receptacle, a failed device, or an open at the breaker/switch.
4. Meter reads about 120 V hot-to-ground but 0 V hot-to-neutral? Hot is present, neutral is open. The neutral connection is broken upstream, classically a loose backstab or a failed splice. The outlet is hot but cannot complete a circuit.
5. Outlet is dead only intermittently or after a heavy load? Heat-stressed, loose connection (often a backstabbed terminal) that opens when warm. Inspect the receptacle and the feed-through connections for scorch.
6. A whole string of outlets went dead together from one point? The open is at the upstream device or junction that feeds them all; trace to the last working outlet and inspect its load-side connections.
7. Outlet works only when a switch is on? It is a switched receptacle by design; not a fault.

Confirming diagnosis

Pull the dead receptacle (breaker off, verified dead) and inspect. A backstabbed connection that has gone open is the most common find: a discolored, loose, or arced stab terminal. Confirm an open hot or neutral by powering the circuit and metering the incoming conductors at the box: the conductor reading 0 V relative to its partner is the open leg. Work upstream to the last receptacle that still has both hot and neutral; the open is in the connection between it and the dead one. For GFCI cases, identify the controlling device and confirm the downstream wiring is on its load terminals. For switch-controlled outlets, confirm with the switch. Use a receptacle tester to flag reversed polarity, open ground, or an open neutral pattern as a cross-check, but trust the meter for the actual voltages.

Remediation

Tripped GFCI or breaker: reset and resolve the underlying cause. Failed receptacle: replace it with a properly terminated device, using screw terminals or listed back-wire clamps rather than push-in backstabs. Open hot or neutral from a loose backstab or splice: re-terminate the connection at the offending upstream device or junction, pigtailing feed-through connections so a single device failure does not kill the downstream string. Heat-damaged device or conductor: replace the damaged parts and correct what overloaded them. Switched outlet mistaken for dead: explain it to the customer. After repair, re-meter the outlet for about 120 V hot-to-neutral and hot-to-ground, near 0 V neutral-to-ground, confirm correct polarity and a present ground with a tester, and verify under load.

References

• National Electrical Code (NFPA 70), Article 406, Receptacles, Cord Connectors, and Attachment Plugs.
• NEC Article 210.8, Ground-Fault Circuit-Interrupter Protection for Personnel.
• NEC Article 300.15 and 314, junction boxes and conductor connections.
• NEC Article 110.14, Electrical Connections (termination requirements).
• NFPA 70E, Standard for Electrical Safety in the Workplace.