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Okay I'm going to explain exactly how this works. You will need to reference the wiring diagrams section 4-4 for the headlights and 2-1 for the fog lights.

The first thing you need to understand is an incandescent bulb acts like a low impedance resistor in a circuit. There is continuity between the terminals. So if only one terminal is connected to power it will 'pull up' the other side to +12v if it is not grounded (bulb off). A LED or HID does not work like this - there is no continuity between the terminals.

As per 4-4 when the headlights are switched off the main headlight relay is off so they get no power.

When the headlamps are switched to on (one click past the parking lights and high beams off) the retractor relay activates the motors to raise them and then turns the headlight relay on. This provides power to the lights which pulls up the ground side of the high beams to +12v since the low/high beam switch is only grounding the low beam side. The pulled up ground of the high beam is connected to the fog light switch see 2-2 which when closed uses this to power the coil in the fog light relay. You can rewire this in the center console to get power from the illumination circuit instead so the fogs will work when the system is in parking, low beams or high beams. This is a common mod just search the forum. Obviously with LED/HID headlights they won't pull the high beam ground side to +12v because there is no continuity so the fogs won't work unless you do the rewire or add some continuity.

When the high beams are switched on, it grounds the high beam lamp only. So the fogs turn off as the power for the switch and relay coil is now a ground. The ground side of the low beams is disconnected so it is pulled up to +12V. This is connected to the power side of the high beam indicator on the cluster. Again with HID or LED lamps this won't work as there isn't continuity so the high beam indicator won't work. Only easy fix is to add some continuity.

The good news is lots of older cars work like this. So there are products on the market that add a low impedance resistor in parallel with the headlamp to provide this continuity. Because it is in parallel it won't drop the voltage going to the lamp, it just used a bit of current when the light is on. If you use one of these with each LED or HID lamp then the system will work as designed. I still recommend the fog light rewire though because it allows you to use them as driving lights with the parking lights on when driving at dusk/dawn.


Make sure you use resistors. Some are a little circuit with capacitors and only work on newer cars. For ours you need the resistor based ones. There are lots on Amazon but you need to get the right ones.
 

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Here are some on Amazon


Here is the fog light rewire thread, he bridges it with a new wire but I just cut the power wire to the switch and connected it to the power side of the map light as it is a permanent mod for me.

 

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Here's relevant diagram. High-beam indicator & foglight trigger are on voltage-divider circuit, interesting...


@Vokey975j, I'm not kidding when I tell you this is an easy 5-minute fix. I used to build and sell heavy-duty battery-cables & headlight harness for Porsches with 50-year warranty. It's been 25-years and not single one has failed or come back. They sometimes pop up on eBay selling for double what I charged for them.




My shoppe installed aftermarket standalone EFI systems. Would build vehicle-specific harnesses for Accel DFI, Austronic, Autotronic, Electromotive TEC, Haltech, LinkECU, Megasquirt, MoTeC, SDS-EFI, Wolfe 3D, systems. Then dyno-tune.



I built my own wideband O2-sensor from individual parts.


So I know what I'm talking about when I tell you this is simple 5-minute fix. It took me longer to write this post than it would take for you to fix this problem. But you gotta give me more data to work with.

1. Please confirm which wires are plugged into which terminal at headlight bulb itself. Post photo of back of headlight plug on harness showing wire colours going into connector.

2. Get multimeter and learn how to use it to measure voltage and resistance. I'll probably need you to take some readings later once we know where each wire goes.

5-minutes to get your lights working!!! You've probably wasted way more time than that already!!!
 

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Success!!!!!!! Thanks to all who helped with this battle. The lights work great. I used Amazon.com: H4 LED Headlight Wiring Harness [Negative Switched Conversion] [Fused] H4 Head Light Relay Harness Kit for 9003 H6054 H5054 H6054LL 6014 6052 6053 Subaru Toyota Head Lights : Automotive
from Amazon as recommended by 4SFED The installation was easy and did not have to drill any holes. I did not have to use the resistors I purchased. The high beam indicator may be a little dull but that’s ok. I willupdate you as I. Drive it some more but rarely drive it in the dark due to deer

Thanks again!
 

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Napa filters says they don't fit out cars. What have you found?
I have the Napa NightVision led's on my 1996 tacoma even though they are not supposed to work. I did have to buy an H4 relay harness for about $25 off of amazon to get them to work but well worth it to me. The harness fixes the Toyota ground issues on older models.
 
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