[fat tire]

2019 Equinox had standard reverse lights. i switched to LED. when the new bulbs were installed i started the car and placed it in reverse. the LED bulbs were shining bright. i replaced the deck lid cover and shut the car off and shifted to park. the LED bulbs had a low glow. i removed everything and removed the Led bulbs and rotated them 180*. started, shifted to reverse, bright as could be. shifted to park , engine off, still a low glow. removed again installed original bulbs. ALL IS FINE
any ideas

 

[BogiesAnnex1]

Something is putting power on them. This could be a ground side “leak” from something that stays powered up all the time. One way to check is with the key switch off disconnect the battery ground then put a volt meter between the ground cable and the negative terminal to see if there’s a voltage. Don’t turn anything on with this hooked up like this as any high amp item turned on is likely to smoke your meter.

Bogie

 

[fat tire]

Something is putting power on them. This could be a ground side “leak” from something that stays powered up all the time. One way to check is with the key switch off disconnect the battery ground then put a volt meter between the ground cable and the negative terminal to see if there’s a voltage. Don’t turn anything on with this hooked up like this as any high amp item turned on is likely to smoke your meter.

Bogie
but wouldn't the factory bulbs glow?

 

[LATECH]

Now that I have re re read your post , and looked at the EWD for the Reverse lamps I will hazzard a guess
More like I will try to theorize I guess
The backup lamps also have a camera that powers from the same circuit
Also a feed goes to the radio (dont know why)
Power comes from the lighting module when reverse is activated, also When the key is shut off,when in park.
Then the lighting module powers the lamps, runs a timer, then kills the lights after a preset time.
There is likely a residual voltage stored in the camera and radio circuit that discharges through the incandescents, but because they need quite a bit of current to light you dont see it.
However, the LEDS use so little current and are not a low resistance path to ground so may continue to illuminate dimly as a result of said condition of the backflow of resdiual current
almost like flyback voltage if you will.The incandescent would bleed the voltage down without you noticing probably

My GTO has a hefty stereo system.
It has a 1 farad cap next to the subwoofer hooked directly to B+
If I unhook the battery for the car , with the door open, dome light on, the LED dome light stays lit, and slowly dims for about 15 seconds and then goes out
You pickin up what I am puttin down?

Dome light hooked to a capacitance that is charge, slowly discharges through t he LED
It would dim much quicker with and incandescent,