Main electrical panel beside a subpanel with its cover removed

Finding an open neutral or bootleg ground at an appliance outlet

A bootleg ground is a receptacle where the ground terminal has been jumpered to the neutral. Three-light plug-in testers cannot detect it, and a reverse-polarity version puts line voltage on the appliance frame. This guide uses meter readings and an external ground reference to find it, then refers the repair to an electrician.

Cross-checked ~20 min moderateBrands: All

Before you start

Live receptacle measurements are caution steps: insulated probes, dry hands, one hand where possible
If the frame of the appliance reads voltage to a known ground, do not touch it; unplug from the cord end and stop using the outlet
Receptacle and wiring repair is electrician work; mark the outlet out of service

Diagnostic steps

Unlock all 7 steps with expected values

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OnCall Tech is a reference tool for trained technicians and can make mistakes. Always disconnect power and confirm with the manufacturer's documentation before you work.

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