Ghost voltage/current?
 

Probably not do it yourself or may not be big deal but here goes?

I replace bad 4 foot LED light in my garage with another 4 foot LED kit, different brand but guts looked same (from china). Simple job removing and rewired the hot, neutral, and ground. Used same hole for mounting so when quickly and easily.

Reset breaker, turned switch, and got lights. Now the weird part. When garage was kind of dark the new LED are faintly lite and the other old one was not? Which the other light kit did not do. Now I got ghost stray voltage causing the light to have faint glow in one of the lights?

Also new light lights up before the other?

I looked in switch which feed comes from multiple plug with fault breaker, didn’t see much except the nurtural was connected to light switch and hot wire tied together?

My thoughts builders may have wired the switch wrong? (most diagrams the hot wire to poles on switch?) which still get current do to alternating?

The new light might be more sensitive to ghost voltage that was there all the time?

Any thoughts?

Hmmm, something is not right.

Any chance the neutral and ground wires are swapped?

Maybe temporarily disconnect the ground connection at the new light and see if it changes?

If so, may be a defective light with a high resistance path to ground.

OP, give me a call, send a PM so we can get together.

If I read your post correctly, it sounds like you have 2 LED lights. I am GUESSING that there is a wiring issue. I have seen situations where the switch opened the NEUTRAL wire and NOT the HOT wire. If there are surge suppression capacitors in the lights, these can provide a leakage path with enough voltage to cause the lights to come on dimly.

In any case, I would go over all of the wiring from the circuit breaker to the lights. Also of there are any switched outlets on this circuit, unplug any devices that are plugged in and see if this changes the lights. Also, using a quality voltmeter, check the voltages to GROUND with the switch turned OFF on all of the devices connected on this circuit.

Does it fade away after a few hours?
Is it on a 100% mechanical switch? Or a dimmer, smart, timer, etc?

Regular flip light switch. It faintly lite enough when garage is dark to see it. It don’t fade away. The old light which had same LED internals didn’t do it.

Yes two LED light wired from same switch. As noted the switch wired by neutrals and black Hot wires are wired together which I suspect is wrong? Which looks like lights were add on some time years pass? I checked the plug in circuits up stream with A.W.Sherry circuit checker and it says ( by yellow lights that light up) the line wired correctly?

I suspect the black hot wires should be connected in light switch and the neutrals wired together? But I can’t figure how that would cause very small phantom current flow?

Try flipping breaker off and see if it goes out. If yes, then (safely **) take apart the wire nut on the hot wire junction. Breaker on. If light still off all the way, bad switch.

If hot is off (disconnected or breaker off) and light is still dim, you have a serious problem where neutral is not bonded to ground somewhere.

** if there is a possibility that there is stray voltage involved, you need to be cautious not to be in the middle of any possible path between any wiring. Neutral to ground. Hot to anything.

Kind of following that, but why would one light be faintly lite and not the other one? I can only see the side poles on the light switch and can’t see what maybe wired in through back of switch if anything. This looks like getting over my head unless the switch is bad or hot wires need to connect to switch instead of the white neutrals?

Shut off the breaker and see what happens

Ok I shut off breaker and the faint light went out. I also while had breaker off I gained access to light in question wires with breaker off no current at black (hot) to ground and no current at white to ground.

Now with breaker on and switch off the light faintly lite, I took ground off at light no noticeable change. I check voltage with light switch off at black to ground 120 volts, same with white to ground 120 volts.

Now with breaker off checking from white to black at light connections I get .007 volts. Now with breaker on and switch off at black and white at the light I get 1.5Vs. I guessing that 1.5V is enough to cause the faint light?

Hmm, could be if the neutral is being switched or inductance from a power wire?

Tips to Stop LED Lights From Glowing When Off | LEDwatcher

https://youtu.be/0Ospzqy78iY?si=rvLdObKqFwEmVi4V

So here’s how wiring goes. Main breaker to GFCI wall outlet, to regular wall outlet, to switch, out to two LED lights.

I know it wired right through GFCI, through wall outlets. Only thing possible wired wrong at switch were common going through switch instead of black, black tied together (all wiring diagrams I’ve seen with switch and two lights show blacks through switch and white commons wired together). When I test the GFCi the dim light goes out and no voltage at light. IMO it’s either the cheap LED light KIT or switch. I forgot to check switch with multi meter when in off position see if any voltage bleed. I haven’t gone into the other light see if same 1.5v bleeding there.

OP, it looks like you have a wiring error, and there is probably a slight difference between the to lights even though they look the same, and this is causing one to stay on dimly. If you KNOW what you are doing, I would turn off the breaker, and trace all of the wiring and correct the connections, then test the lighting. Basically, all grounds bonded together. All neutrals bonded together. Black HOT wire from source to switch, and the black wires to the lights on the switched side of the switch.
I have equipment to help if needed.

You are correct! Just got done rewiring switch. I guess the common (white) wires run through switch instead is the hot (black) bleeds enough ghost current (in my case 1.5 volts) to faintly lite the LEDS.

I had verified earlier that wiring was right up to switch.

I rewired the black through switch and no current flow out of switch.

Thanks everyone who responded for all for help!.

Problem solved!.

Great job - well done!