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You need an extra 5-pin relay connected to the high beam relay output, where the normally closed position allows power to flow to the fog lights, but when energized cuts off the fogs. I’m waiting for my 5-pin relays to come in the mail, but plan on doing a full write-up on the install in my LE hybrid model in a few weeks (once I complete the install!). Got help from others on the forum here and will go through detailed steps.

The info I have is compartmentalized into snippets from YouTube videos, messages, and instructions that came with my kit. I’m also converting the push button it came with to one that fits in the spare under the climate control, so had to re-wire the plug. It’s fairly straight forward but took a lot of offline testing with a 12V battery pack (8 AA) cells to test the relay, backlight and indicator functions. I used this setup as it can’t provide as much current to cause damage. I’ll write it up all on here when done.

You can’t just tap the low beam power to the lights as they stay energized when high beams are on on these models.

In any case, here’s a description of how 5-pin relays work (link below)z You’d need to connect to high beam power through terminals 85 (+ve) / 86 (ground) or 2 (+ve) / 1 (ground) the case of a micro relay. Fog light power goes into terminal 30 or 3 and the output to the fog lights goes to 87a or 4. Keep in mind the notes on polarity as the relay may come with a protection diode which means +ve can only be one way across the coil. I’d install the cut-off relay after the 4-pin relay that came with your fog lights.


Edit— and here it says the pin out I have is opposite for the Denso micro relays. So look up your part online
 
You need an extra 5-pin relay connected to the high beam relay output, where the normally closed position allows power to flow to the fog lights, but when energized cuts off the fogs. I’m waiting for my 5-pin relays to come in the mail, but plan on doing a full write-up on the install in my LE hybrid model in a few weeks (once I complete the install!). Got help from others on the forum here and will go through detailed steps.
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I understand all of this, my problem is locating a wire that I can tap into that provides 12vdc. I initially though of tapping into the wire going into the 3-light fixture, but the triggering wires all provide 5vdc, not 12vdc. I tried the Automatic High Beam Switch, but, likewise, the voltage is 5vdc.

The headlight connector pinout is as follows (testing with meter):
1 - 12vdc all the time
2 - gnd
3 - 5vdc all the time
4 - 5vdc when high beams are off, 0vdc when high beams are on

I cannot find a 5vdc relay that will trigger with the minimal current available on the connector. My current thought is to remove the steering column shrouds and test the control arm, hoping I can find a triggering 12vdc.

If you know where I can tap into please let me know, I am stumped at this point.
 
You can tap in anywhere between the high beam relay and the headlight fixture under the hood. That side is fused 20A and should be able to handle a relay input. You’d want to install a smaller fuse on the wire to your relay after the tap.
 
You can tap in anywhere between the high beam relay and the headlight fixture under the hood. That side is fused 20A and should be able to handle a relay input. You’d want to install a smaller fuse on the wire to your relay after the tap.
Canadian vehicles must be different. While the wiring diagrams I have show a high beam fuse (H-LP HI LH) it doesn't exist, I just have one fuse for the entire 3-beam headlight assembly (H-LP LH). Ditto with the relay, there is one relay for the entire headlight system, everything else is in the headlight assembly itself.
 
Canadian vehicles must be different. While the wiring diagrams I have show a high beam fuse (H-LP HI LH) it doesn't exist, I just have one fuse for the entire 3-beam headlight assembly (H-LP LH). Ditto with the relay, there is one relay for the entire headlight system, everything else is in the headlight assembly itself.
Oh, you are right. Mine is the same as yours (there’s an H-LP RH as well). Another Canadian (I thought?) user had separate hi and low beam relays. Maybe production year changes. Or perhaps Toyota put these in the bottom of the fusebox (there is a button level, usually has stuff like the alternator fusible link) in Canada so people couldn’t defeat their Daytime running lights. Noted that I have no DRL fuse or relay as well, and single headlight fuses (no separate for high and low beam despite being marked as such).

This changes my plans (that I was sure were going to work). Will investigate more.
 
Oh, you are right. Mine is the same as yours (there’s an H-LP RH as well). Another Canadian user had separate hi and low beam relays. Maybe production year changes. This changes my plans (that I was sure were going to work). Will investigate more.
Good luck, really. I have examined every wire from the steering column to the AHB switch, through to the lights themselves. Everything is 5vdc. My current (no pun) attempt is to find a 5vdc relay that will work. The problem is (where the pun comes in) is that the current available is very low, too low for a mechanical relay. I tried a SSDR (solid state) but that did not work for the same reason, but it was a 40A relay. I've been working with a company that sells relays, they said the 40A is too large, they sold me a 10A relay, the lowest that will work in this application. If it doesn't work then I have to start looking into PC board relays, but they're not meant to handle the heat in the engine compartment.
 
Good luck, really. I have examined every wire from the steering column to the AHB switch, through to the lights themselves. Everything is 5vdc. My current (no pun) attempt is to find a 5vdc relay that will work. The problem is (where the pun comes in) is that the current available is very low, too low for a mechanical relay. I tried a SSDR (solid state) but that did not work for the same reason, but it was a 40A relay. I've been working with a company that sells relays, they said the 40A is too large, they sold me a 10A relay, the lowest that will work in this application. If it doesn't work then I have to start looking into PC board relays, but they're not meant to handle the heat in the engine compartment.
Interesting. Another user I’d communicated with has a Hybrid Limited in Canada and had separate hi and low beam relays.

I assume for the LE’s they put all the switching assemblies in the lamp assembly itself.

When you say solid-state module, are you talking one of these?
PAC TR-7 Universal Trigger Output (Black) PAC TR-7 Universal Trigger Output (Black): Amazon.ca: Electronics

here’s the manual:

Can take a 0.8 to 16 volt trigger and be programmed to give a 12 V output of various types up to 2A, which can drive a relay.
 
Interesting. Another user I’d communicated with has a Hybrid Limited in Canada and had separate hi and low beam relays.

I assume for the LE’s they put all the switching assemblies in the lamp assembly itself.

When you say solid-state module, are you talking one of these?
PAC TR-7 Universal Trigger Output (Black) PAC TR-7 Universal Trigger Output (Black): Amazon.ca: Electronics
No, I didn't see that when I searched Amazon, doesn't say what "low voltage" is, this is what I ordered:

 
I
No, I didn't see that when I searched Amazon, doesn't say what "low voltage" is, this is what I ordered:

I found the manual after I had already posted and updated with the link, it can take anywhere from 0.8 to 16 V as a trigger.
 
I'm not sure how it works, it would have to be NO, and able to handle 10A if attached to the trigger side of the first relay, or 20A if attached to the load side of the original relay.
The “20 A” relay that came with my fog light kit has a resistance of 100 ohms across the coil side. V=IR so even assuming vehicle voltage is running at 14.6 V (let’s say, 15 V for simplicity), I=V/R or I=15/100 = 0.15 A or 150 mA. So I’m saying one could tap the low beam 5V wire to the module, use that as a trigger, then drive a standard relay with that device) since it can support up to 2A.
 
The “20 A” relay that came with my fog light kit has a resistance of 100 ohms across the coil side. V=IR so even assuming vehicle voltage is running at 14.6 V (let’s say, 15 V for simplicity), I=V/R or I=15/100 = 0.15 A or 150 mA. So I’m saying one could tap the low beam 5V wire to the module, use that as a trigger, then drive a standard relay with that device) since it can support up to 2A.
That was my plan, but thus far I haven't been able to find a relay that can trigger off of the low beam wire. I connected the - side to ground, the + side to the low beam wire, and nothing. I had nothing connected to the load side of the relay, just the trigger side was connected. I connected a multimeter to the load side on the ohm setting (audible when near zero) and the meter did not go to zero.
 
That module
That was my plan, but thus far I haven't been able to find a relay that can trigger off of the low beam wire. I connected the - side to ground, the + side to the low beam wire, and nothing. I had nothing connected to the load side of the relay, just the trigger side was connected. I connected a multimeter to the load side on the ohm setting (audible when near zero) and the meter did not go to zero.
That module I posted seems to be able to do the job, but giving its programming flexibility I’m a little worried that it might interpret a power glitch as programming and start flashing my fog lights like police wigwags.
 
That module

That module I posted seems to be able to do the job, but giving its programming flexibility I’m a little worried that it might interpret a power glitch as programming and start flashing my fog lights like police wigwags.
Mine is supposed to arrive by end-of-week, will post when I see what happens.

Can you upload the manual on the one you found?
 
This is an interesting problem to solve. I wonder if something like this (says it works on 5V) driving a 12V 10 A automotive relay would do the job. Or, even on its own m.

 
The only problem I see is the 2A limit.
This is an interesting problem to solve. I wonder if something like this (says it works on 5V) driving a 12V 10 A automotive relay would do the job. Or, even on its own m.

Possible. It could not go in the engine compartment since it is not protected from weather. It's similar to what I am trying, but mine is sealed. There are many issues: length of wire from the headlight to the relay (current drop); heat dissipation (10A is a lot of power); available current to trigger the relay. Toyota is not making this easy.
 
The only problem I see is the 2A limit.


Possible. It could not go in the engine compartment since it is not protected from weather. It's similar to what I am trying, but mine is sealed. There are many issues: length of wire from the headlight to the relay (current drop); heat dissipation (10A is a lot of power); available current to trigger the relay. Toyota is not making this easy.
A 10 A relay doesn’t draw 10 A in the coil. For example, this one:

AGT 5V DC 5-Pin Coil SPDT Power Electromagnetic Relay 10A 250VAC PCB SSR Type (Pack of 10) Amazon.com: AGT 5V DC 5-Pin Coil SPDT Power Electromagnetic Relay 10A 250VAC PCB SSR Type (Pack of 10): Automotive

Contact rated for 10 A, but 5 V side is 0.36 to 0.45 W. since P=IV this means 0.36/5 to 0.45/5 or 0.072 to 0.09 A draw off of the 5V side. But the coil side is also rated for “7 A” which I believe means it needs to be protected by a 7A fuse at maximum (in case of a fault). The switching side can handle 10A. Of course the packaging is less than ideal again.

I’m most worried that these 5V lines come straight out of a computer module in the car, and worry about blowing out the ECU.
 
So here I think is our circuit diagram for these headlights. If you have “automatic” headlights everything is ECU driven. See the notes at the top of page 2 with the * as you won’t have all these features.

these were all posted in a thread somewhere under 4.5. I’ll see if I can dig the link up. There’s an ECU and non ECU controlled schematic, seems like we are dealing with the ECU one.

Edit - the link is in the Thread below, page 2 mid-way down. There’s a big zip file, you’re looking for HL-ECU. My attachment got deleted to this message. I’ll try putting it on again.

 

Attachments

I don't know your background, but if this does not work the engineers at the place where I'm buying the relays made a different suggestion, but it requires the ability to solder. I've done this many times so it's not a problem for me.:

PC Relay: CPC1218Y
Breadboards: 1608
 
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