Tail lights stuck (dimly?) on

[dannyC]

I noticed today that my tail lights are stuck on, even when the vehicle is off. My TJ has LED aftermarket tail lights where the LED array dual purposes as both brake lights and nighttime tail lights (just the brightness changes), so it's not clearcut to observe which "light" is stuck on, however the array is definitely not at "brake light" brightness. It's either at nighttime tail light brightness or possibly even less (hard to gauge in daylight).

I've tried pulling the 1 (park lights), 2 (stop lights), 11 (DRL), and 13 (turn signal) fuses behind the glovebox (one at a time, not at once), hoping to narrow something down, but the tail lights remained dimly on during each.

It's been raining a lot the past week or two, so my gut says this has electrical short written all over it. But, from there I don't know what to do with that information or where to start. The one unexpected observation against that theory is if I enable my hazard blinkers, the LEDs are properly "off" in between the bright "on" intervals. (coincidentally this reminds me of a time I had a GFCI outlet go bad and an attached LED nightlight would be dimly on, until attaching an actual load to the circuit at which point it would go off)

I'm hoping some of the great minds here who have "seen it all" might have some clues. Thanks!

 

[macleanflood]

Try unplugging the brake switch under the dash.

If that doesn't work take apart the shroud around the steering column and unplug the multifunction switch.

-Mac

 

[CreepinDeth]

I've tried pulling the 1 (park lights), 2 (stop lights), 11 (DRL), and 13 (turn signal) fuses behind the glovebox (one at a time, not at once), hoping to narrow something down, but the tail lights remained dimly on during each.

That's what I was gonna have you do, but u did it already
Read
https://theautoinsiderblog.com/why-do-led-lights-stay-on-when-switched-off-in-car/

If ur still worried , you can test for parasitic draw on the circuit

 

[dannyC]

Appreciate the thoughts from both!

The following morning I went out and reconnected the battery and the tail lights immediately turned back on, so I concluded it probably wasn't a luminescence or residual capacitance issue of some sort as described in the shared article. So, I started pulling random fuses until I finally got them to go out by pulling the "horn" fuse under the hood of all things.

Because it seemed, given this, that there was possible some current crossover going on with the lines going up into the steering column, I was nervous to go in and touch the wiring/switch as Mac suggested since the airbag wiring is in the same vicinity. (this anxiety may be unfounded but I don't know what I'm doing enough to make that call)

It later turned out the shorting was maybe happening somewhere else, because even with the horn fuse removed, later that night in the dark I noticed the reverse lights were now on (the wiring of which I don't see why would be in the steering column). I also later noticed that a notepad in my glovebox was damp, so my guess is with all the rain there was a leak coming down the firewall area and affecting the area around the glovebox fuse box.

I've let it dry out over the last couple of days with the battery off, and hooked it back up today and so far no problems. So, my thought right now is my best solution going forward is to look up what rubber seals/gaskets are in that area that might need replacing (?), to prevent recurrence in the future

 

[macleanflood]

Until you fix it WD-40 might be your friend getting water out.

Horn wiring is all on the driver's fender on my 97...you've got front trim lights there...do your trim lights glow like the tail lights?

-Mac

 

[MikeE024]

I noticed today that my tail lights are stuck on, even when the vehicle is off. My TJ has LED aftermarket tail lights where the LED array dual purposes as both brake lights and nighttime tail lights (just the brightness changes), so it's not clearcut to observe which "light" is stuck on, however the array is definitely not at "brake light" brightness. It's either at nighttime tail light brightness or possibly even less (hard to gauge in daylight).

I've tried pulling the 1 (park lights), 2 (stop lights), 11 (DRL), and 13 (turn signal) fuses behind the glovebox (one at a time, not at once), hoping to narrow something down, but the tail lights remained dimly on during each.

It's been raining a lot the past week or two, so my gut says this has electrical short written all over it. But, from there I don't know what to do with that information or where to start. The one unexpected observation against that theory is if I enable my hazard blinkers, the LEDs are properly "off" in between the bright "on" intervals. (coincidentally this reminds me of a time I had a GFCI outlet go bad and an attached LED nightlight would be dimly on, until attaching an actual load to the circuit at which point it would go off)

I'm hoping some of the great minds here who have "seen it all" might have some clues. Thanks!

If problems come back, I would probably check out the Multi-Function Switch and its plug.

I found my MFS's plug burnt and pins shorted a couple years ago causing all kinds of abnormalities. Splicing in a new plug and installing a Napa Echlin MFS resolved the problem.