Diagnosing and Fixing Open Grounds

Diagnosing and Fixing an Open Ground

Step	Diagnostic Action	What You Are Checking	Expected Result	If Problem Found	Typical Fix
1	Confirm tester reading on multiple outlets on the same circuit	Determine if the problem is local to one receptacle or circuit-wide	Only one outlet shows open ground	Ground likely disconnected at that box	Proceed to inspect that receptacle box
2	Turn off breaker and remove receptacle cover	Check if ground wire exists in the box	Bare or green wire present	Ground wire missing entirely	Cable may be old 2-wire cable without ground
3	Check ground wire connection to receptacle	Ensure ground wire is connected to green screw	Ground firmly attached	Wire loose or disconnected	Reattach wire to ground screw
4	Check wire nut splice of grounds inside box	Grounds must be tied together and pigtailed to outlet	All ground wires tied together	Ground splice loose or missing	Re-splice grounds and add pigtail to receptacle
5	Check metal box bonding	Ground wire must bond to metal box if metal box used	Box connected with ground screw or clip	Box not bonded	Add ground screw and bonding jumper
6	Check upstream receptacle on same circuit	Ground may be disconnected in previous box	Ground continuous through circuit	Upstream ground wire loose	Reconnect ground splice upstream
7	Inspect cable entering box	Verify ground conductor is intact in cable	Ground wire continuous	Ground broken or cut	Replace damaged cable segment
8	Measure continuity from receptacle ground to panel ground bar	Verify entire grounding path	Near-zero resistance	No continuity	Ground conductor open somewhere in circuit	Trace wiring back toward panel
9	Inspect grounding bar connection in main panel	Circuit ground wire must terminate on ground bar	Ground wire properly landed	Ground not terminated or loose	Attach wire to grounding bar
10	Verify grounding electrode system	Ensure panel ground is bonded to ground rod or service ground	Ground rod present and bonded	Missing or loose grounding electrode conductor	Repair connection to ground rod