Wiring light bar relay trigger into high beam wire without premium LED lights

I have a 2025 limited and I do not appear to have the premium LED headlights. I have read and reread all the can bus how-to threads and it looks like the options are giant pain in the ass, pulling your dash apart or leaving the can bus computer in the engine bay where it's not designed to be weatherproofed. I figure if my lights aren't working by can bus and I can just tap into a high beam wire I can avoid all that nonsense. I have searched this forum and I have searched Google in general. The only thing that comes up is first and second gen Tundras. Does anybody know if the 3rd gen is all can bus regardless of the headlights? Or which wire to tap into on the standard light connector?

 

Pretty sure this is the correct wiring diagram without the canbus

 

Here is the wiring diagram of the one with canbus

 

You can see the difference in the wiring

I'm not sure what the pin outs are though other than Pin 3 being ground



I'm going to go with soft blue on left hand headlight and light green on right hand headlight being high beam power.

I would test with a circuit tester to see if that's accurate or not.

If those don't work, I would think it'd be the gray on the left and red on the right.

 

I was thinking about doing the same thing. I've got the standard wiring (no can-bus) for my SR5.

One question I've always had, is there a legend somewhere with the abbreviated letter and number scheme on the connector body? I know some are self explanatory like "E" being for earth/ground.

Like in this example below, the "AT1" and "AS1"?? Even if there was a legend for "A" or "B" in the circles on the connector body too, that would be helpful. I've referenced my system circuit diagram I don't know how many times and was just curious. I've never seen a legend. I had TIS at some point for 3 days but didn't see anything in there while I had access.

 

I did manage to find this.

 

I appreciate the help. Harness plug #1 is definitely for the lights. I unplug it and the entire lights on that side go out. I assume plug#2 is for turn signal and DRLs. #1 has four wires: red, white/ black, dark green, and turquoise. I tried to test current with a multi meter but I can't get the probe far enough down in the plug. I figured at that point it was time to back away from the electronics. The wiring diagrams confuse the shit out of me, although I do appreciate the interaction on the thread. I may just order the can bus reader and tear apart my dash, lol

 

Just wire the trigger to an actual switch. That way you can use the light any time you want, not just with high beams. Plus, anytime you try to flash somebody for any reason, you’re really going to cause more distraction with the light bar

 

Yeah, that's the intent. To use the in dash button that comes with the light bar kit as a Master interrupt so I can disable the light bar completely and use the high beams as normal. But when I do use the light bar. It is operated with the high beam stalk control So I'm not trying to stab around low on the dash next to my knee trying to find the button.

 

The problem with that is that if you’re high beam circuit is also connected to a 12v trigger, whenever you turn the switch on, you’ll be sending 12v back into the high beam circuit. So your high beam will now be also controlled by the switch.

 

Can you check Amps, wire by wire?
But I also don't recommend wiring bar with high beam together. It needs to be controlled separately IMO. Easy to do

$30 KAIWEETS Digital Clamp Meter Multimeter with D-Shaped Jaw for AC/DC Current & Voltage, Auto-ranging 4000 Counts Voltage Tester with Flashlight Backlight, Measuring Temperature Continuity Diode NCV

Ampermeter

 

This is all super doable. Do a little bit of research. That is not the topic of debate. The question is which wire is the high beam on the 3rd gen Tundra?

 

Maybe you just need to do a little bit of research.

 

Maybe your face needs to do some research

 

lol. Are you 12 years old?

 

So you see how childish this back and forth is. If you don't understand the concept and don't have anything to contribute then no need to post anything. Just Google search "wiring light bar off of high beams". You'll see a s*** ton of results. This is a very common thing. Not trying to argue with some dude about a switch. I'm just asking where the high beam wire is And you don't have anything to contribute to that topic. So please stop arguing

 

I understand the concept. And I also understand these trucks in great detail. Your headlights, turn signals, all run through the ecu. There are no relays, flasher modules, etc. The circuits run through, and are controlled by the ecu. These trucks are super sensitive to any type of voltage changes being everything runs through the ecu. You’re trying to reinvent the wheel on a $60k truck when the wrong back feed could literally brick the ecu. Obviously you’re the “know it all” type and being a “know it all” won’t get you any help by anybody knowledgeable on this board. Good luck in your endeavors. Keep researching. But tundras aren’t tacomas. The wiring and ecus are not even remotely the same.

I understand wiring the switch off the high beams.
I understand wiring them from a switch.
Both are 12 volt triggers to get power from the battery. You do one wiring configuration or the other. Not both.

 

Well, so far you haven't provided any help anyway so no loss there

 

Oh. I did some research on the topic. Found some information. I didn’t intend on commenting back as it literally took 5 minutes and figured you could find it just as easy.

 

Just cruising the internet starting arguments, winning them, feeling good about yourself. Sounds like a 12-year-old.

 

Good luck. I feel great. Lol.

 

At least for my part in this is I'm just trying to figure something technical out. Whereas you're just here to fill a void your life

 

Do some research. The answers are out there. Literally in this exact forum. From years ago.

 

I will do that. Because I am in search for something. But dude, go spend time with your family and quit arguing with people on the internet.

 

Atta boy

 

It seems like he will add a switch to the light bar's power supply wire (could be from the battery directly). That wire will also have a NO relay that closes when the high beams are activated. This is likely why he's looking for the high beam wire - to close the relay. Thus when highbeams are activated AND the switch is 'on' his light bar turns on. If the switch is off then the light bar does not turn on.

This configuration will not back-feed the highbeam circuit like you're saying.

 

So, just to be clear.... you did some research and figured out how to wire a light bar into high beams using a a normal in dash switch? And now you know how to do it? So, you did some research and learned something you were arguing couldn't be done?

 

Not a normal switch. It’s a complete standalone module. And you’re not getting it done with a standard relay and wiring harness. And yes. The system is a mix of Canbus and canbus global. I said it can’t be done by the means you’re trying to do it with. And I’m correct. You need a module that is a canbus interface that gives you the ability to change from high beam switched to manual switched. You’re still running the module through the canbus system. Now….this was done back in 2022 on a 22 model. As with Toyota, they love to change wiring and ecus regularly. So a module that works with a 22’ might not work with a 25’ and the wiring def most likely won’t be the same.

So yea. I found all of that out from a 5 minute search on Google which brought me back to these very forums.

 

Yeah. I've already read all those threads. And if you see, I've commented on them as well. You're not dropping knowledge bombs. You just learned something tonight. And if you had already known, I bet your first response probably would have been, "Nah. You need a can bus connect interface like this one". But I guess you didn't know what that was until about 20 mins ago.

https://www.ncs-systems.com/canm8-highbeam.html

 

You’re right. I learned about the module tonight.

But what doesn’t add up is that you said you read all of those old posts. But are still here asking if it’s canbus and trying to wire it to a regular 4 pin harness knowing it’s not going to work without a module that currently shows no compatibility with a tundra and would have to be special ordered.