High Beam Indicator Not Working After Koito Install - LED Still The Fix?

Gretsch

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So as luck would have it I went to get my 60 series inspected today. I fixed my horn this weekend to get it to pass and while that worked, it still failed inspection. The Texas Inspection Nazis failed it because the high beam indicator does not work. So now I need to get it sorted. I believe it stopped after installing the OEM Koito H4 upgrade but I didn't worry about it because it didn't matter to me. Now it does. The high beams work fine, its just the indicator on the dash that doesn't. In Texas, that's a cardinal sin apparently.

This thread seems to indicate simply adding an LED bulb in the dash will get the high beam indicator to work again with the Koito upgrade. Is this still the way to have the high beam indicator work with the Koito upgrade? Not sure how this upgrade could be OEM and not allow the indicator to light up. I am guessing a bit that my issue is due to the Koito upgrade. The bulb could just as easily be burned out, but it seems this is a common thing with the H4 upgrade so wanted to check on if there is any new info on making this work. The indicator used to work, that much I know. I am just not sure when it quit but think it was just after the Koito upgrade. Thanks in advance for any guidance here.
 

t140frank

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Same thing here, I swapped in the Koito H4 Toyota upgrade.
I originally just changed the lights out and ran it off the original wiring harness for a few months, when ran like this the HI beam indicator worked fine.
Finally got around to installing the supplied wiring harness, and now the HI beam indicator doesn't work.
Haven't tried messing with it yet, been busy doing a head job and about a million other things I didn't know needed fixing :frown:
Let me know what you come up.
 

OSS

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The blue high beam indicator in the gauge cluster IS important. Without it, it’s too difficult to tell at a glance whether you’re blasting oncoming traffic with your hi beams or not. Mine didn’t work for a long time and I can tell you it’s a BAD experience not having that blue indicator. Blinding oncoming traffic with high beams could cause an accident- maybe fatal.

If the Koito led lights use a separate wiring harness- you’re in luck.
The ARB headlight wiring harness comes with THREE relays to ensure that the high beam indicator works. Just use an ARB headlight harness instead,

At this point in time - Toyota doesn’t care jack about the FJ60. That LED headlight upgrade sort of works and that’s good enough for them.
 

Gretsch

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The blue high beam indicator in the gauge cluster IS important. Without it, it’s too difficult to tell at a glance whether you’re blasting oncoming traffic with your hi beams or not. Mine didn’t work for a long time and I can tell you it’s a BAD experience not having that blue indicator. Blinding oncoming traffic with high beams could cause an accident- maybe fatal.

If the Koito led lights use a separate wiring harness- you’re in luck.
The ARB headlight wiring harness comes with THREE relays to ensure that the high beam indicator works. Just use an ARB headlight harness instead,

Thanks for the reply @OSS. I have read about the ARB harness. The Koito does come with a harness so if its a matter of swapping out to the ARB to make this work, then so be it. Seems this is common enough a problem with the Koito kit that I was hoping to retrofit the Koito harness somehow to make this work. Not sure how this kit would not include a way to illuminate the hi-beam indicator as part of it. Had I realized that I most likely would have just gone with the ARB H4 kit instead of the Koito.
 

CruiserTrash

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I'm in the same boat - neither incandescent nor LED bulbs were working for me. At least one piece of this puzzle is the floating stock headlight plug that you're left with after using the Koito harness. @HemiAlex hipped me to a small module from HID Kit Pros - it plugs into that empty headlight connector and I would guess it's a dummy load.

I got that installed and now my high beam indcator works but is very dim. You can see it at night, but not at all during the day. Oddly enough, only incandescent bulbs are working. LEDs don't come on at all. In the photos below, the indicator is on in the daytime shot - clearly bot visible at all.

CA631151-6D6B-4D67-850A-3BDDC66424F0.jpeg
A05A605A-18BD-40EB-B534-A1838FD4F81C.jpeg
237536EA-024B-41FA-B895-F4567396FE80.jpeg
 

Gretsch

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I'm in the same boat - neither incandescent nor LED bulbs were working for me. At least one piece of this puzzle is the floating stock headlight plug that you're left with after using the Koito harness. @HemiAlex hipped me to a small module from HID Kit Pros - it plugs into that empty headlight connector and I would guess it's a dummy load.

I got that installed and now my high beam indcator works but is very dim. You can see it at night, but not at all during the day. Oddly enough, only incandescent bulbs are working. LEDs don't come on at all. In the photos below, the indicator is on in the daytime shot - clearly bot visible at all.

View attachment 2810760View attachment 2810761View attachment 2810759

Interesting. So what side did you plug the Koito harness into? Driver or passenger side factory plug?
 

t140frank

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Mine is plugged into the passenger side.
I think the we could probably run a jumper from the unused factory plug high beam slot to the high beam slot on the Koito harness and close the circuit.
 

CruiserTrash

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Mine is plugged into the passenger side.
I think the we could probably run a jumper from the unused factory plug high beam slot to the high beam slot on the Koito harness and close the circuit.
Whoa, hold up. There's a high beam connector on the Koito harness?? It's been a year since I installed it so I don't really remember. I'll have to go back and look.

That makes me wonder if there's only one harness with the kit, or one for 60s and another for 62s.
 

t140frank

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I'm talking about the actually the headlight terminals themselves, they have three prongs. HI Beam, Low Beam, and a common ground.
I think the issue is the HI Beam plug terminal that's on the unused factory harness plug is not going to ground and leaving an open circuit and that's why the HI beam indicator is not lighting up.
Since the original harness is still hooked and sends signal to the new Koito harness through the passenger side only its leaving the unused plug on the drivers side as a open circuit, we should just be able to jump over top the passenger side HI beam terminal and it should close the circuit.

Makes sense in my head o_O
 
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I'm talking about the actually the headlight terminals themselves, they have three prongs. HI Beam, Low Beam, and a common ground.
I think the issue is the HI Beam plug terminal that's on the unused factory harness plug is not going to ground and leaving an open circuit and that's why the HI beam indicator is not lighting up.
Since the original harness is still hooked and sends signal to the new Koito harness through the passenger side only its leaving the unused plug on the drivers side as a open circuit, we should just be able to jump over top the passenger side HI beam terminal and it should close the circuit.

Makes sense in my head o_O
in the stock wiring the 3 prong plug has a common power and the low and high beams go to ground. The wiring is pretty much backwards to most other vehicles that switch the power where the toyota switches the ground. So if the Koito harness converts the headlight signals to a power switched system then this will prevent the high beam indicator from functioning properly unless they have made provisions for it.


here is a diagram that is from another mud thread...showing how to use the stock wiring to trigger a set of relays and convert from ground switched (stock) to power switched. You can see the indicator in the bottom middle is wired in parallel through the selector switch so that on low beam both 12v goes to 2 grounds on parallel wires. Both wires will see a full 12v but half the current which prevents the indicator bulb from lighting up. When the high beam is selected the high beam indicator path sees the full current and lights the bulb. I'd guess that in the Koito harness changes a path to ground somewhere and is changing the current that travels through the indicator....would have to study the koito for a minute to see what its doing

1634135308607.png
 

Gretsch

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I think the issue is the HI Beam plug terminal that's on the unused factory harness plug is not going to ground and leaving an open circuit and that's why the HI beam indicator is not lighting up.
Since the original harness is still hooked and sends signal to the new Koito harness through the passenger side only its leaving the unused plug on the drivers side as a open circuit, we should just be able to jump over top the passenger side HI beam terminal and it should close the circuit.

OK help me out here, I'm admittedly a bit slow with these circuit diagrams. Are you saying here we should be able to connect the hi beam terminal from the passenger side to the hi beam terminal on the driver side and have this work? or can we just run a lead from the driver side factory harness hi beam terminal to ground and have this work? Thanks for the help here.
 

CruiserTrash

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Has anybody drawn out the Koito harness? I think the answer lies in putting the two schematics together.
 

Gretsch

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I tried to find a diagram today for it while looking around but didn't come up with anything. I'm sure its been done but I just couldn't find it in the time I had today.
 

Gretsch

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Did find the original instructions from another thread which I'll add below to have it in here. Not sure it helps but might show something someone finds useful:

28429f80-ef07-4b64-bf8f-2b4e17839016-jpeg.2411303

848ac186-958b-460b-877a-2d4c4161d194-jpeg.2411304
 

CruiserTrash

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@Gretsch I was just thinking of the original instructions, thanks for posting. I do some electronics repair on the side and can read "schematics" (these aren't really schematics, more of a layout), so let me chew on both of these diagrams and see what I can come up with.
 
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@Gretsch I was just thinking of the original instructions, thanks for posting. I do some electronics repair on the side and can read "schematics" (these aren't really schematics, more of a layout), so let me chew on both of these diagrams and see what I can come up with.
I can post the actual wiring diagram tomorrow. But the essence of it is the indicator either needs to be wired differently or something creative has to be done to remedy the koito
 
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Had the same problem after the Koito upgrade, but my high beam indicator was working fine until the swap. The LED dash bulb fixed it right up.

I suspect it has something to do with the fact that the original dash wiring is now controlling low resistance relays (50-100 mA) versus actual bulbs (5-10 A), but someone smarter than me can probably figure that out.

Honestly the LED dash bulb is a worth a try at a $10/5 minute fix.
 
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Had the same problem after the Koito upgrade, but my high beam indicator was working fine until the swap. The LED dash bulb fixed it right up.

I suspect it has something to do with the fact that the original dash wiring is now controlling low resistance relays (50-100 mA) versus actual bulbs (5-10 A), but someone smarter than me can probably figure that out.

Honestly the LED dash bulb is a worth a try at a $10/5 minute fix.
makes sense. If the amperage gets dropped in the circuit it wont be able to power the bulb.
 
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Here is the 1985 circuit

1634218224462.png


The common has 12v when the headlight switch is turned on and power and Hi/Lo activate when given related paths to ground through the headlight switch.

The high beam indicator pulls its power off of the low beam headlight circuit. When the Low beam is on the indicator is in parallel with the ground path for low beam and thus the current is split which doesn't provide enough to power the dash bulb. When the high beam is selected the indicator is now a series connection to groun on the low beam side and has enough to illuminate the indicator. My mind questions why the low beam doesn't stay even when the high beam is selected but clearly there is only enough current left to light the indicator bulb...not sure if there are other resistors in the circuit not shown in the diagram.
 

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