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PotooBrigham
07-01-2024, 12:29 AM
Been attempting to install LEDs for a bit now, and I've been trying to figure out why one set of retrobrights will illuminate while the other doesn't.
Currently have the front wired for a quad-low beam setup; the curious thing is the pair of Classic White (LFRB120) units I bought turn on satisfyingly bright no matter which socket I plug them in, while the Modern White (LFRB140) units turn on dimmer than the sealed beams on low, and won't activate at all on high. The functioning Classic White lights also emit quite a bit of heat, not sure if that's normal.
https://i.gyazo.com/23da747bc5168c7872869737cac620b0.png

https://i.gyazo.com/1bf27d98c5633abd757e3312712d8396.png

I've replaced both related fuses, and have a relay on the way, but I'd love to know what's the normal current supposed to be coming out from the lights, volts or amps. I'm still learning wiring bit by bit; my prior experience is installing a backup camera, so I guess I came into this project a bit too confidently?

DMC-Ron
07-01-2024, 05:53 AM
Perhaps I can help on a couple of items. The Holley LFRB120-1 LED headlamp is listed as a dual high/low beam headlight rated 25W low and 35W high. This should equate to 2.1 amps low and 3.0 amps high current draw. I could not find a connection pinout but going from the DeLorean wiring harness the blue/white wire is high beam, the blue/red wire is low beam, and the black wire is negative ground. You need to insure that the car wiring is connecting to the correct terminal on the headlamp. This may require a repositioning of the wires in the DeLorean connector, or an adaptor that allows you to cross-connect.

Now, remember that the only time all four headlights are intended to turn on is for high beam. When low beam (dip beam) is selected, only the two outermost lamps light. The outer lamps are the dual intensity lamps and have dual elements, one for high beam (35 watts in your case) and low beam (25 watts for your LED lamps). For testing purposes, you should see 12v on the left and right blue white wires when high beam is selected, and 12v on the left right blue/red wire when low beam is selected. Occasionally the black wire is not providing a good ground and needs to be corrected either by finding the poor connection or adding a supplemental ground wire.

Ron

JBaker4981
07-01-2024, 11:58 AM
Check your wiring --- Looks like maybe an H4 conversion? You can pull the pins from the connector on the DeLorean side and plug them up individually (just make sure they do not touch). I recommend verifying Low Beam to Low Beam, High Beam to High Beam, Ground to Ground. IIRC, you have to flip the positions of two of the pins for H4s

JBaker4981
07-01-2024, 12:02 PM
I just looked at my pictures from my LED Conversion --- Red to Blue/White, Black to Black, Yellow to whatever the third color is. You may be getting resistance through the H4 adapter so on top of what I mentioned in my last post, I'd nix the adapter and rearrange the pins in the factory DMC Connector after you test the wiring configuration.