Dome light always on but super dim

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Fittrjoe

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67 Barracuda restomod
I switched to LED bulb in my dome light about 2 years ago. Never an issue… nice and white compared to before.
Now when doors are closed and ignition off it’s on super dim
Checked door switches one at a time/ unplugged and still on ever so slightly
Weird thing is it’s not even draining the battery over a 3 day period for instance… been monitoring the battery with Volt meter just normal.
Dash switch next?
 
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I'll lay my quarter on aftermarket jukebox wiring. We can't tie the memory to the yellow wire. That tiny draw will kill the battery in time. I've been wrong before but, that's where I would look. I think the lamp in trunk is on same circuit. Easier to check anyway.
 
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Since leds take very little current a tiny current leak can cause them to light.

The bulbs get power continuously and the door switch or the headlight switch provide a ground.

Only places among with the wiring that can make the ground to keep it on.
 
Something wet, leaking. By that I mean leakage CURRENT due to wetness, corrosion, etc. Determine for CERTAIN which dome lamp terminal is NOT the power one, then, with all doors closed and the HL switch for certain turned off of the dome position, take a resistance reading on the highest meter scale. If it reads anythng except open/ infinity, you are on the right track.

Now inspect and pull the door switches loose, one at a time. See if the problem goes away. They are more likely to be wet/ corroded. If not, leave them both disconnected, and pull the headlight switch connector. If that does not do it I don't know what to tell you. Any other lamps in the circuit that might be prone to leakage around the sockets? C pillar? etc?
 
@67Dart273 My first thought was a bad door switch. Then @Oldmanmopar mentioned the headlight switch, and that is a possibility too. I think I's check the door switches first and then the headlight switch. The 56 Studebaker Power Hawk I am helping my friend with had some crusty door switches. He was going to look for some new ones, but I told him to let me play with them. The door switches are pretty simple. I took them apart and rebuilt them. They work great now.
 

LED's can do some crazy things. I have LED bulbs in my garage door opener and they glow all the time. You would never notice it until you walk in the garage at night in the dark.
 
LED's can do some crazy things. I have LED bulbs in my garage door opener and they glow all the time. You would never notice it until you walk in the garage at night in the dark
Your garage door opener probably uses solid state switching for the bulbs.


If that does not do it I don't know what to tell you
Then it's in the wiring. Cracked insulation and moisture
 
AND NOW YET ANOTHER annoying story from the old days

In the '80's I spent about a dozen years in HVAC/R service/ repair and help with installations. We had a young man here, VERY successful locally with a restaurant, built a big house out of town, LP gas, lots of "stuff." Commercial grade kitchen. Back in those days, the contractors always pushed our boss to get the furnace we'd installed online, for heat. So I went out there, late in the day, winter, already headed towards end of daylight. The site was a mess. It had started to thaw, then snowed a lot. There was over a foot. No body there, I had to wrestle up what was going on with electrics, being supplied by a temp meter/ pole out away from the house. Couple of extension cords, etc. I had a then new electrical tester, small lightweight, had a long row of LEDs all the way from 12V to 600V. I clipped it to the furnace case for a quick ground point, stabbed the probe into this cord, and ALL THE LIGHTS in the building, also on cords, went out!!!! WTF!!! So I had wade down and up through a ditch, through a big berm, and through more deep snow to the pole. YUP. GFI and it's tripped!!!! Back then, these were pretty new, at least in this area, and I wasn't hip on how they worked. I thought I shorted the probe some how. So I went back in and DID IT AGAIN!!!!

I finally got it fired and left. THEN I did some research on how GFI's work. This of course is BEFORE Al Gore invented the internet.
 
AND NOW YET ANOTHER annoying story from the old days
Mine is along the same issue as the top is having.

Commercial office building, new electrical runs to newly installed cubicles.

The electricians left a flex conduit with exposed and un terminated wires loose on the floor under a cubical.

I got out my trusty volt meter and checked the wires, 80v AC. what the heck? Traced it back to the breaker panel and the breaker was off. My first thought was bad breaker, then exposed wires along the run making slight contact.

Then it donned on me. Induced current from other wires in the same conduit. Yep add a load to the wire with 80v Ac and the voltage dropped to 0. Had unchecked it with a Wiggy it would have tested 0.

I didn't but I could have touched the wire with my bear hand and not gotten bit!
 
Mine is along the same issue as the top is having.

Commercial office building, new electrical runs to newly installed cubicles.

The electricians left a flex conduit with exposed and un terminated wires loose on the floor under a cubical.

I got out my trusty volt meter and checked the wires, 80v AC. what the heck? Traced it back to the breaker panel and the breaker was off. My first thought was bad breaker, then exposed wires along the run making slight contact.

Then it donned on me. Induced current from other wires in the same conduit. Yep add a load to the wire with 80v Ac and the voltage dropped to 0. Had unchecked it with a Wiggy it would have tested 0.

I didn't but I could have touched the wire with my bear hand and not gotten bit!
A few years ago a cable modem died, this was Time Slymer. Tech came out and claimed the port was blown up and claimed "I was backfeeding power into the port." The only thing connected to the cable was THEIR modem!!! So I got my fluke and showed him that the coax "showed voltage" (it is not far from the power line) AND THEN showed him that the garage metal roof showed line voltage as well, yet I could grab it and ground and not get zapped.

Nevertheless they put in their comments that I somehow was backfeeding their coax!!! I had one hell of a time with them. FINALLY they sent out a woman, who actually knew something, and after showing her and explaining to her, she relented
 
along the lines of the above comments, our garage light went out. replaced the bulb, still no light. checked the breaker, it's on. Dad says to replace the porcalin fixture. I had my truck in the garage for repairs and had just about enough room to put my head in there sideways to work on it. turned the breaker off. undid the fixture, and then wires but I could feel the fuzz on my face standing on end. got it put back together and it worked. told Dad what happened and he laughed. and he did mention the back feeding stuff.
 
When I worked at the wheelchair joint, this was a building that was originally some sort of shop, maybe for trucks. Have very tall roll up doors clear to the ceiling. The company had installed a pre-fab bolt together mezzanine floor, and there was not much headroom upstairs. I could reach up and touch the ceiling. In one corner, the rails for the door came up and along the ceiling, and closeby was a row of flourescent lamps.

They had hired a girl who had problems. One day she evidently ran out of stuff to do, and the company was slowly converting the lamps to LED. I guess someone had told her "she could do that."

I was working at my bench, and got up to stretch my legs. I heard something over in that corner, there were stock shelves blocking my view, so I walked around and here she was. She was standing on a 2- step stool, in a tank top. Her head was inches away from the lamp housing, and her bare shoulder was inches away from the door track. A bit of movement, and she could have contacted them. Here she was, changing out the fixture LIVE. Bear in mind if you were darn careful, you could do this, but IT IS NOT LEGAL and she was not an electrician

I walked over and stood there, and said as gently as I could, "do you know what you are doing with electrics?" "Not really." "Do you realize this could kill you? You need to not do this."

BEAR IN MIND this is against electrical code and OSHA. I went down and talked to the boss, and I might as well have told him that someone was eating lunch. No real reaction.
Part of my then workbench. Notice the huge American Beauty soldering iron, and DIY lamp controller in a box. The buss bars I had to solder into the drive module PC board required A LOT of HEAT!!!
IMG_0042cs.JPG

Just a general view of part of the electronics bay. The closest bench was dedicated to building/ assembling, repair, and rebuild of hand control modules.

The one just to the left had a stereo microscope, was dedicated to surface mount.

Further on down and in the corner were the test jigs for doing bench tests of the electronics packages.

My bench is down towards the end. Since the demise of the in-house electronics package, the "electronics" bay is tremendously reduced. That is allegedly what cost me my job, even though I could built everything else. They just wanted someone cheaper.
IMG_0019cs.JPG

Building a bunch of accessory switchboxes. I don't remember what, I would assume these are lockout/ limit switches for power seating. You must either limit chair speed or lock it up depending on what is being done with power seating, tilt, elevate, etc.
IMG_0200cs.JPG
 
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glad you saved the lady from injury. we would do it live at the hardware store swapping ballasts. never touch two wires or one wire and metal. I'd cut and wire nut it. was at a Saturday breakfast at church about 2 years ago. fellow asked if I would help change light bulbs. sure, I can climb a ladder to change tubes with an eight foot ceiling. turned out it was switching to LED bulbs. so, 7 classrooms, 3 hallways and part of the basement, most are now LED's. don't think the shoulders and neck could put up with anymore.
 
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