Step-by-step: fixing a hot ground

A hot ground is a life-safety failure. You measure voltage between the equipment grounding conductor and a known neutral or earth reference, and you get something other than zero. That voltage is energizing every metal enclosure, raceway, and exposed conductive part bonded to that EGC. Find it, isolate it, fix it. Here is the field workflow.

Confirm the condition before you tear anything apart

Start with a known-good meter and known-good leads. A loose lead or a meter on the wrong scale will send you chasing ghosts for an hour. Verify the meter on a live receptacle first, then move to the suspect circuit.

Take three readings at the receptacle or enclosure: hot to neutral, hot to ground, and neutral to ground. On a healthy 120V circuit you expect roughly 120V hot to neutral, 120V hot to ground, and under 2V neutral to ground under load. Anything above a few volts neutral to ground points to a shared neutral, a bootleg ground, or a true fault energizing the EGC.

If you read full line voltage from ground to a known earth reference, stop. Do not touch any bonded metal. Kill the feeder at the panel and work from there.

Rule out the easy stuff first

Most hot grounds in residential and light commercial work trace back to a handful of repeat offenders. Walk these before you pull devices or open junction boxes downstream.

• Bootleg ground at a receptacle, neutral jumpered to the ground screw to fool a three-prong tester. NEC 250.146 and 406.4(D) prohibit this.
• Reversed polarity combined with a bootleg, which puts the ungrounded conductor directly on the EGC.
• Loose or missing main bonding jumper at the service, leaving the grounded conductor and EGC at different potentials. See NEC 250.24(B) and 250.28.
• Shared neutral on a multiwire branch circuit with a broken neutral, pushing return current onto the EGC.
• Damaged cable where the ungrounded conductor has nicked or arced to the EGC inside a stud bay or under a staple.

A plug-in tester is fine for a first pass but it lies about bootlegs. Use the meter for anything that matters.

Isolate the circuit

Kill the breaker. Lock and tag if anyone else is on site. Verify dead at the point of work with the same meter you just proved live. NEC 110.16 and NFPA 70E apply here, full stop.

Once the circuit is dead, disconnect the EGC from the panel ground bar at the breaker you just opened. Leave every device on the circuit connected as it was. Now use a continuity tester or low-resistance ohmmeter from the disconnected EGC end to the ungrounded conductor of that same circuit. A short reading confirms a hot-to-ground fault somewhere on the run. An open reading means the fault is upstream, on a different circuit sharing the raceway, or at the service.

If continuity is open, also check EGC to neutral. A hard short there is a bootleg or a misbonding downstream of the service.

Walk the circuit and find the fault

Split the run in half. Open the receptacle or junction box closest to the midpoint of the circuit, separate the EGC at that point, and re-test continuity from each side. The half that still shows the short contains the fault. Repeat the split until you have it cornered to a single device, box, or cable run.

1. Identify the midpoint device on the circuit map.
2. Pull the device, separate the EGC pigtail from the box and the downstream conductors.
3. Ohm out each leg back to the panel end of the EGC.
4. Move your split point into the half that reads short.
5. Repeat until the fault sits between two adjacent boxes, then inspect the cable between them.

If the cable between two boxes ohms hot to ground but looks clean, check every staple and every drilled stud. A drywall screw through NM cable is the classic find, and it can sit dormant for years until someone bumps the wall.

Repair to code, not to "good enough"

Damaged NM or MC gets cut out and replaced, not taped. NEC 110.12(B) and 300.5(E) cover the integrity of conductors and the prohibition on damaged wiring being installed or left in service. If the fault is a pinched conductor inside a box, replace the device, re-strip clean, and verify the box has the proper clamps and bushings per NEC 314.17.

If you found a bootleg ground, remove the jumper and pull a proper EGC back to the panel. On older two-wire circuits without an EGC, your code-compliant options are listed in NEC 250.130(C) and 406.4(D)(2): GFCI protection with the "No Equipment Ground" label, or a retrofit grounding conductor run to an acceptable point.

If the main bonding jumper or grounding electrode system is the culprit, that is a service-level repair. Coordinate with the POCO if you need to pull the meter, and re-bond per NEC 250.28 and 250.50 before re-energizing anything downstream.

Verify before you button up

Re-energize the circuit and repeat the original three readings at every device on the run. Hot to neutral and hot to ground should match within a volt or two. Neutral to ground should sit under 2V under normal load. Any GFCI on the circuit should trip on the test button and on a real fault from a plug-in tester.

Document the readings. A photo of the meter at each device, with the device location written on a piece of tape in frame, takes thirty seconds and saves you on the callback. If the fault was a shared neutral or a service-level bonding issue, note it on the panel directory so the next person on the job has a fighting chance.