LMC headlights/harness kinda wonky

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Girth

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Garth
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1989
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V2500 Suburban
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350
Installed LMC's "Custom Dual 165mm" headlights and their "Heavy-Duty" harness (PN 36-3581) this afternoon. The new lights ARE a vast improvement, that's for sure. They don't work right though. :rolleyes:

On "Low" as far as the truck is concerned (1984 C10 by the way), just the upper lights are on...... but that's the "High Beam" side of the bulb that's on. Definitely the "Hi" judging by the light that's cast on the road. On "Hi", blue lights on in the gauge cluster, all four headlights are on, but I'm guessing on the low beam filament on the bulbs? Definitely casts a shorter beam on the road..... but all four are on, and thats the high beam setting on the switch. lol

All four lights have a 9007 bulb in them, so all four should have the capability of both Low/Hi...... but they're working backwards, in more ways than one. lol Not REALLY an issue, I just have to have the high beam switch selected, to have all four on their Low setting. :emotions122:

Soooo yeah, something is wonky in that wiring. That's what I get for being lazy. Should have made my own harness. LMC's harness isn't REALLY "plug and play". I mean it IS, but the whole setup is a bit wonky. Harness has the standard plug for the OE lights on it, but the 9007 bulbs use a different plug, so the light housings come with a short adapter pig tail. Basically theres twice the plugs in the harness now, extra points of failure. Oh...... and there's no fuses in the harness, so that was something I added.

I actually installed two of these today, one on the wife's Burb too and that one (36-3582) was even more wonky in how it seems they want you to connect to the original harness. I tested it earlier, made sure everything came one, but that uses different bulbs for Low/Hi.

So yeah..... long day, brain isn't ready to figure it out. Gonna drive the truck to work tomorrow and just be happy I can see the road in the dark on my way home..... with all four lights on their low setting. lol
 

PrairieDrifter

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Mason
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Suburban k10, bonanza k10, k30, k20, c10, gmc 1/2ton
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I had to repin some wires on mine. Ever since then though I've had no issues, not even a bad relay. I still haven't gotten around to hard wiring those extra connectors yet either. No issues and it works good. Would probably go with painless wiring next time though.

Sure has paid for itself in headlight switches and pigtails though! Even though the headlight switches these days are junk anyways :anitoof:
 

75gmck25

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Bought one of the LMC kits many years ago. Wiring seemed a little chintzy (not really HD) at the same, but it’s lasted a long time.

Since it did not include fuses, I added a power point on the fender near the battery and connected the relays into constant 12 volts at the battery using a fusible link. Ended up using that same power point for a pigtail to connect my trickle charger.
 

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