Fog light turning off with high beam

Has anyone found a work around to keep the fog lights on when the high beams are on? The only solution I’m thinking of is to install a fog light specific relay and switch. Thanks

 

If you're traveling at speeds where high beams are necessary, you're traveling too quickly for the fogs to be of any use. On the other hand, if it's foggy enough that you need your fog lights, turning on your high beams would would impair your ability to see, due to all the reflection. Any particular reason you need your fogs, headlights, and highs on?

 

Off road trails.

 

Just add a set of aftermarket auxiliary lights if you need the extra visibility on trails.

 

Pfffft……put a high beam relay and JOIN it to the fog wiring. Like Y adapter. When on low the truck runs the fogs, turn to high beam and the truck will shut off the fogs, same instant the high beams activate the fogs. Done it on 3 trucks now ( not my 3rd gen though ). Easy peasy local auto parts store will have the relay.

 

I'm running Diode Dynamics DOT replacement fogs off my Switch-Pros. A +12vdc signal from the trucks fog light circuit is wired to one of the Switch-Pros triggers. There are two triggers you can do what you please with. The other +12vdc trigger is on the parking light circuit.

This allows the fogs to activate when they're called for via the turn signal stock, and you can also run them with the high beams, in addition to any other auxiliary lighting. Off road of course. Terrible idea on road, but that goes without saying. I know this probably doesn't help you much, but it is certainly an option and would almost certainly cover you for any future electrical additions to the truck. One great thing about the Switch-Pros is you typically do not need any sort of fusing except for the primary that powers the module. It uses solid state relays and a microprocessor to fuse all of the circuits up to 80 or 85% of the circuit's rated capacity. You could also do the same with some old school mechanical relays. Unfortunately the 3rd gen lighting has a fair amount of can-bus interaction which can make what was once a simple work around, now a rather large pain in the ass.

 

I like the way you went about this. A lot of the wiring is canbus in the new tundra but I wonder if I can find a good wire for the high beam power. I’ll look around.

 

I used those connectors that you put over a wire, and add the 3rd wire and crimp it together. Never had an issue ANd I crimped to the high beam wireand the 3rd wire went to the relay which then went to the fog.

 

Did you find that high beam wire next to the headlight?

 

Yes Remember I never did this with the 3rd Gen but i doubt its different cause i have been doing this for 40 years. Every vehicle i have ever owned has had a driving/fog/light bar on it Figure out which wire in the light cluster is the high beam ( google is your friend or this forum )
I used a tester and held it against the wire then had some one click on the high beams to confirm it. The rest is easy Follow the relay instructions. If you cant get them let me know and I can scan them to you

 

If you are going to move forward think about a driving lights versus altering the fogs.

 

INSTALL a relay……….all you are doing is stealing the 12V off the high beam wire AFTER the factory relays. ……. You are not jumping a factory relay.

it’s light bar 101 for installs

 

Assuming you do realize that it’s illegal to run high beams & fogs at the same time.

 

Think of it this way (simplified, but the fundamentals are there)

You have the headlight which receives a constant +12vdc and ground. Then you have communication lines going to said headlight that interface with the vehicles CAN-BUS system. Inside the headlight is a microprocessor and a solid state relays that do all the on/off switching for your high beams, low beams, turn signals, auto-leveling etc.

When you turn on your headlights inside the truck, you are simply sending a signal to a computer, which then tells the headlight what it wants done. The headlight then processes this signal and does what was asked of it through the solid state relays inside of it.

 

I have hundred of hours working 12v auto electrical systems. I’ll dig into it this weekend and will report back. This will be for a 2023 sequoia sr5. From what I can see so far can-bus is heavily used.

 

[Fairly] simple.
See this thread for reference:
https://www.tundras.com/threads/how...-bus-driven-hi-low-parking-headlights.110264/

If you have CAN-BUS premium headlights, get and wire up the CANM8 "high beam" device to your truck, then run its trigger output wire to a relay and connect it's output to the fog lights.
This way, once your high beams come on, the CANM8 will read the signal, provide 12V+ trigger to the relay, which in turn will activate it's own 12V+ source and feed the fog lights (or anything).

Food for thought however: better off with a combo light bar (flood|spot|flood), which once lit up will probably render your fog lights, low and high beams, pretty much useless.
Mine does at least.

Hope this helps.
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