Here is one for you electrical geniuses. I am putting dash indicator lights in my '40 Plymouth. I put in 1/4" LED lights, two green for turn signals, yellow for cruise control, and blue for high beam. Everything works except the hi-beam blue light. I am using the standard vintage floor push button hi/lo switch but the indicator is on for both hi and lo lights. It is only wired into the hi circuit but knows when the lo is powered. Guess I need to find old fashioned incandescent grain-o-wheat bulbs for my hi beam.
I would check the wire going to the light to see if it is powered in both lo and hi beams first. I think that's probably where your problem lies. The LED won't light unless you send power to it.
I took the plug apart on the foot switch and wired an LED to the hi beam terminal and ground, hooked up both hi and lo beams. Lead wire to dash light is out of circuit. Stupid LED glows for both positions even though there is no current going to it or the hi beam circuit when lo beam is powered. I checked voltage with a multimeter and for sure there is no voltage when the LED is glowing on lo beam position. I hate electronics!!
An LED only needs about 1.5v forward voltage to light up. Try setting your voltmeter to a lower DC voltage range. There has to be at least 1.5volts there for something to light up. I reckon you have a leakage current going to the high beam terminal. Try completely removing the switch and connecting up the appropriate wires with a clip etc, see what that does.
Low beam maybe back feeding the LED, try one bulb at a time just incase you have a bad bulb. I seen a guy tear a whole school bus apart looking for a short, finally found one of the tail light bulb had the filaments touching inside it.
Added on of those blue LEDs to the footswitch in our 64 Elco. When the brights are on the damned thing is so bright it'll just about blind you. Just FYI..
I think you are on it. My system is incandescent headlights and retro looking LED tail lights. The tail lights are tricked up with pre-flash stop lights. Had to add resistors to the stop light circuit to get the flashers to work. System is over-electronic. I just ordered some grain-o-wheat bulbs I'll replace the LED with. Old tech solution.
If an LED is too bright, you can put a 1/4 watt resistor in series with one of the leads to reduce the brightness. Start with a 100 ohm unit, and go up in resistance from there .
Could you possibly have the "blue" high indicator bulb wired into a single common ground of both the high and low beams?
I was just thinking about the same thing. A poor ground at either lamp would apply a voltage to the high filament and back to the selector switch where he is wired in.
I used the same blue LED for high indicator on my OT Power Wagon . The LED will stay lite for a few seconds after switching to low beams . Just a slight power feed will keep it glowing . And yes the Bastard is way too bright . I colored over mine with a sharpie , that helped a bunch . I have learned old stuff likes old stuff , don’t try to mix it up , you can’t cook on bottled gas if you try it .
I had the same problem as willys36 when I installed a Painless harness. LED s for turn and high beam, but the blue high was on all the time. Just brighter on high beam. I separated the bulb grounds and got the same result. Then I decided to eliminate the foot switch and wired in a 40 amp relay to a toggle on the dash. That worked great for about a minute, then the headlights turned off. No blown fuses or filaments but I discovered that by eliminating the indicator lamp the headlights come on stay on and can be switched low to high and back with no failure. At least with the toggle I will know that the high beams are on.
Any wonder why I hate electronics? Bad ground is a good guess since 99.999999% of electrical problems on rods are grounding problems. Grain -o-wheat incandescent bulb should work. Or not.
Reminds me of the time I put a small LED light on my electric fan switch so I would know when the fan kicked on. Never noticed in daylight, but at night the light would glow when you were going down the road with the fan shut off. Apparently there was enough airflow through the radiator it turned the fan blades, turning it into a mini generator.
Try this: Disconnect both headlight harnesses from headlight bulbs. Now see if the indicator lights in low beam and in high beam. If it still lights in low beam, then there is a wiring issue. If indicator only lights in high beam, then one or both headlight harness grounds are poor.
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