Lessons · Electrical · troubleshooting a dead outlet
A dead outlet: check in the order that costs least
Ask what changed, check the cheap things at the panel and the GFCI, test at the outlet with a meter, and only then de-energize, lock out and open it; the fault is almost always a tripped device or a loose connection at the last working outlet upstream.
Hone is a place to practise a career, one idea a day. This is one of its lessons, written out in full and free to read without an account.
What it is for
The homeowner has already tried three things and is standing behind you. An electrician who opens the dead outlet first spends twenty minutes finding nothing, because the open connection is in the outlet before it, or the GFCI in the garage nobody remembered. The order is the skill.
How to think about it
Cheapest first. Is anything else dead: that says which circuit. Panel: a tripped breaker, sometimes sitting in the middle, off then on. GFCI: bathroom, kitchen, garage, outside, basement; press RESET. Meter at the outlet: hot to neutral, hot to ground, neutral to ground; the pattern names the open wire. Then, and only then, breaker off, lock, verify, open the box, and look at the last live outlet's outgoing terminals as hard as the dead one's.
Worked example
Other outlets in the room: two dead, three liveHalf a circuit. An open somewhere between the last live and the first dead.
Panel: nothing tripped. GFCI in the garage: tripped, RESET pressed, still deadCheap checks done. The GFCI reset means it was not the cause this time, or it is downstream of the fault.
Meter at the dead outlet: hot to neutral 0 V, hot to ground 120 V, neutral to ground 120 VThe hot is present. The neutral is open somewhere upstream.
Breaker off, locked, verified 0 V. Open the last live outlet: neutral backstab looseThe fault is in the working outlet, on its way out. Move the wires to the screw terminals.
Restore, retest: 120 V hot to neutral at every outletDone, and proved, not assumed.
Your turn
Hot to neutral reads 0 V and hot to ground reads 120 V. Write which wire is open.
the is open
Solve one, graded on the server
The trap
Opening the dead outlet first. The break is usually where the current stopped, which is the outgoing side of the last outlet that still works. The dead one is a victim, not a suspect.