High Beam Indicator Not Working After Koito Install - LED Still The Fix? (1 Viewer)

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Yeah I can usually figure out mostly simple DC stuff, but just assumed the harness converted things in such a way that the bulbs wouldn't work with the factory wiring. As in the harness was REQUIRED to make the new bulbs work thus making it different from factory somehow. I just never considered that possibility but I should have I guess. I actually kinda thought the plugs wouldn't physically fit the new bulbs to be honest. The Koito harness has those boots on the plugs and I just never looked inside them to see if they matched the factory ones. Another lesson learned here on Mud. Man so many lessons here. Thanks again for this clue.
the only thing you need to watch out for is if you are going to run a much higher wattage bulb on the stock wiring. a 100watt or 150 watt bulb could lead to your stock wiring burning up due to the higher current demand of the bulbs.....this is where the upgraded haresses really shine
 
the only thing you need to watch out for is if you are going to run a much higher wattage bulb on the stock wiring. a 100watt or 150 watt bulb could lead to your stock wiring burning up due to the higher current demand of the bulbs.....this is where the upgraded haresses really shine

So you would say then with the lower wattage bulbs there is little reason to even run the new harness or does it help to provide more light because of the more efficient new wiring the harness has? Set up this way it does not seem as if the lights are as bright at this point running off the stock wiring, one of the reasons for getting the kit in my case. I don't think this is a surprise really but would make me lean towards using another aftermarket harness or make the Koito work to light the indicator. I tend to be a purist with these trucks so the less I change from factory the better IMO. Good lighting was something I thought would be worth changing however.

The irony of having a failed safety inspection because the lights you swapped to make the truck safer causes the indicator to not light having the State of Texas deem it to not be safe. They should have seen it before the swap. :)
 
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So you would say then with the lower wattage bulbs there is little reason to even run the new harness or does it help to provide more light because of the more efficient new wiring the harness has? Set up this way it does not seem as if the lights are as bright at this point running off the stock wiring, one of the reasons for getting the kit in my case. I don't think this is a surprise really but would make me lean towards using another aftermarket harness or make the Koito work to light the indicator. I tend to be a purist with these trucks so the less I change from factory the better IMO. Good lighting was something I thought would be worth changing however.

The irony of having a failed safety inspection because the lights you swapped to make the truck safer causes the indicator to not light having the State of Texas deem it to not be safe. They should have seen it before the swap. :)
I ran the headlights on the original factory harness for a few months before swapping in the new harness. Lots of night driving ETC, for what its worth the original harness never heated up and I actually didn't notice a difference in the brightness when I used the Koito harness.
 
I’ve measured about a 1 volt drop between my battery and the light connector. The newer harness should cut down on that drop but it depends because my oem harness might just be worse than yours.
 
For what it’s worth-
When I was a dumb young hayseed, I thought I’d upgrade the original dim headlights with Hella H4 bulbs and of course I chose the brightest bulbs available- the 80w/100w bulbs.
I didn’t use a headlight harness because way back then nobody made them and there wasn’t an internet to learn about stuff.

Everything worked dandy (or so I thought) for a few years until the excessive current eventually melted the wiring ground connector behind the dash and all my gauge lights malfunctioned or stopped working. Headlights went out too.
 
For what it’s worth-
When I was a dumb young hayseed, I thought I’d upgrade the original dim headlights with Hella H4 bulbs and of course I chose the brightest bulbs available- the 80w/100w bulbs.
I didn’t use a headlight harness because way back then nobody made them and there wasn’t an internet to learn about stuff.

Everything worked dandy (or so I thought) for a few years until the excessive current eventually melted the wiring ground connector behind the dash and all my gauge lights malfunctioned or stopped working. Headlights went out too.
Yikes, I just installed those exact bulbs. But I'm using the Koito harness now so I should be ok.
 
Seth, I never measured the voltage drop, but I couldn't visually notice a difference. My wiring is in pretty good shape, nice clean grounds and that contact goo stuff on all the terminals I've messed with so far.
 
Seth, I never measured the voltage drop, but I couldn't visually notice a difference. My wiring is in pretty good shape, nice clean grounds and that contact goo stuff on all the terminals I've messed with so far.
You are probably getting a minimal drop then. Which is good and a sign of healthy wiring.
 
Yeah if you’ve got a harness you’re fine.

Similarly, I should be OK to run the Koito lower wattage bulbs with the stock wiring? I have the ARB harness on the way so might still use it but would the stock wiring be OK with the Koito bulbs?
 
Similarly, I should be OK to run the Koito lower wattage bulbs with the stock wiring? I have the ARB harness on the way so might still use it but would the stock wiring be OK with the Koito bulbs?
Yes. The sealed beam wattage is about the same as a standard 55/60 watt H4 bulb.
 
Yes. The sealed beam wattage is about the same as a standard 55/60 watt H4 bulb.

Excellent. I might just roll this way then if there is no real difference in brightness between using the harness and not. I'll keep the koito harness in place to see if we can still solve getting the HBI to work with it.

Thanks all for the input here.
 
Well it worked to get me legal:

1634328839582.jpeg
 
So to be clear here @Seth S ..



The ARB wiring/relay harness that seems to make this all work properly is around $140 for reference. Prolly can find it cheaper if I looked around some. Kinda pricey to me.

Quality relays, connectors and terminals/ wire, are expensive. I don't make dual relay sets for less than 120, for ballast and headlights.
There is a big difference. I've seen enough burned LX 100 series low beam wiring and I've dissected enough so called HD relay sets.
I would just caution on using the lowest priced stuff out there.
It's not going to be true wire gauge, rated terminals or connectors. The relays are going to be of the less than a dollar variety.
I'm not trying to sell anything, just advice.
Calculate your loads, wire run length and a hefty temp factor.
 
Update here for anyone still following along. I ordered the ARB wiring harness and an LED for the dash. Got the harness. After thinking about this I am not sure what the future holds for my light setup. I may want to get brighter higher wattage lights for this truck down the road so I decided to go ahead and install the ARB harness. Got it done yesterday with minimal fuss. I can confirm that it does indeed make the HBI function. Works perfectly. I didn't try the LED with the Koito harness. I am not a fan of the LED lighting thing in these trucks. I know its all the rage but I prefer the original warmth of the original bulbs. If I was going to go through all the effort of replacing the HBI light with an LED, I would just replace everything with LED while I was in there. I wasn't prepared to do this at this time. So the end result is I don't know if the LED would have fixed my issue or not. I figured the ARB harness solves multiple problems for me so I went that route.

An unfortunate accident while removing the Koito harness. Some how one of the relays ended up in the street during my removal. I didn't see it. My only indicator it was on the ground was the crunch I heard as the truck that rolled over it rolled by. I thought, "that sounded weird". Looked down to investigate and there it was. So it got destroyed and I no longer have a working harness to test things with. I will see if I can maybe figure out how the harness is wired to see if I can determine why the HBI doesn't work with it. The ARB harness works fine, but it really does not seem that well made. I thought the Koito harness seemed better quality. But the ARB works so whatever. Anyway, that's where I am at the moment with this. Thanks to @OSS for the ARB tip. Worked like a charm.
 
If you want really bright Halogen headlights with an accurate beam pattern- at a good price, look no farther than the Hella Halogen H4 headlights with 100/80 watt bulbs. I used this combo with the ARB harness and I never wished the headlights were brighter.
(100/80 watt bulbs are illegal to use on road - buy nobody will know. Just don’t high beam a cop driving towards you).

https://www.jittruckparts.com/headlamp-7-165mm-h4-12v-ece-002395991



HELLA H4 12V 100/80W Bulb - 358110121 - https://www.jittruckparts.com/h4-12v-100-80w-p43t-358110121
 
@Gretsch If you want to get rid of that Koito harness, I would love to dissect it. I'll gladly pay shipping. The other stuff looks nice too, but I'd love to come up with an inexpensive solution to pair with the inexpensive Koito kit.

@OSS Regarding the Hella 100/80 bulbs, as long as the harness is up for the current draw, the Koito kit should handle those just fine correct? I'd have to see what the wire gauge is. The Koito housings are just housings though, correct? Meaning going from 65/55 to 100/80 shouldn't be a problem for the glass.
 
Meaning going from 65/55 to 100/80 shouldn't be a problem for the glass.

I don’t know anything about the Koito headlamps. All I know is that the Hella headlamps (housings not the bulb) take H4 halogen bulbs which are a standardized base and those 100/80 watt bulbs are H4 halogen bulbs. There also are 130/90 watt H4 bulbs and 65/55 watt H4 bulbs that plug into the Hella lamp too.
The 130/90 watt H4 bulb seemed too extreme to me so I never even tried it.
 
@OSS The Koito "kit" being spoken about here is simply two 7" round H4 housings and an adapter harness. So the lenses just take standard H4 bulbs - hence I was talking about popping the higher-powered Hella bulbs in there. I would think the housings/lenses would be fine, and it would be dependent on the harness wire gauge.
 
Yeah that should work fine. I doubt the higher wattage 100/80 bulbs would burn up the Koito housing. Could always examine them periodically to see if there’s any evidence of overheating inside
 

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