Fog lamps - why only when low-beams are on? Has anyone modded this?

Hi - first post, so hey to folks all around!

Question - why do the fog lamps only work when the headlights are on low? Out here on these 2-lane roads in the West, the foglamps seem useful for seeing things low in the road at 70 MPH, when you have the high-beams on. Has anyone jumped the low-beam relay? Is there any reason not to have foglamps when in high?

To anticipate one question - yes, I probably will install LEDs anyway, but still . . .

Thanks!

 

Yes, people work around this by a bypass of some sort. They seem to vary from generation to generation and not too familiar with gen 1.

It's how most cars are manufactured.

Sure someone can jump in with a solution

Edit: Might be in here

DIY / MODS / TUTORIALS | Toyota Tundra Forum (tundras.com)

(1) DIY: Fog Light Mod | Toyota Tundra Forum (tundras.com)
^
Found Gen 2

 

https://www.tundras.com/threads/diy-fog-light-mod.371/

 

They are designed to turn off when using brights to not blind other drivers.

check this https://www.tundras.com/threads/diy-fog-light-mod.371/#post-5947

 

Yes - I see the Gen 2 and 3 mods, but those use a more complex relationship between the ECU and the lamps. I think the Gen 1 is simpler - perhaps you just run a circuit from the fuse block to the relay, bypassing the low-beam circuit?

It never really made sense that they are disconnected for high-beam use. You use high-beams when there are no other cars on the road anyway, so there is no one to blind!

 

Agreed, makes no sense. Probably one of the first mods I did to this truck.

 

Why? Because of varying state laws. Some states say only a maximum of 4 front facing bulbs may be illuminated when driving. So low beams + fog lights = 4. You turn on high beams and the others stay on, that's 6. You run into issues. Will cops bother you? Probably not but car companies will get bad press for selling a car that does not comply with a certain states law.

 

Hmm. I actually would like it if the low-beams stayed on when the hi-beams came on. But they turn off in my 2001.

That would be another great mod!

 

The main reason fog lights do not work with high beams is that high beams on in fog reduce visibility. The higher intensity reflects off the fog (or snow) and actually reduces visibility due to glare. Fog lights are meant to shine low, under the fog, and to illuminate the road markings so in reduced visibility you can still stay on the road. Amber fog lights are said to perform better from a glare perspective but some people disagree.

 

Illegal af, 10 headlights. Does it roll? Does it float? Does it hover? WHO KNOWS?!?

 

I think they are the same as 4th gen 4runners. Try here.


http://www.top4runners.com/ja/2007/fogmod.html

 

^^^ this is the reason why fogs on low beam only

 

This is 99% correct. The only correction I would make, and maybe I'm just nit picking here, is that high beams don't have a greater intensity, they have a greater, more upward, pattern. He nailed it why you shouldn't run your fogs with high beams, though. Anyone that has a problem with fogs not operating with the high beams needs to quite thinking their fogs are light pods. Fogs are fogs, not off road lights. If you want more light, get a light bar or some other off road lights.

 

Well, they are just lights, set lower. If it is foggy, you might want only them on (without even low beams). But if you want them for general illumination, there they are! I live in a place literally without fog, so it is a little silly to constrain their use simply because of a hypothetical situation.

 

My truck is full of lights... i mean full. Cubes out the ass leds all around. First thing I did when I installed an aftermarket switch box was hook the fogs up to their own switch. They no longer shut off with highbeams. Bright me on the road... youll see heaven for a brief moment. Lol best thing I ever did ngl ditch lights and 4 other cubes plus all leds nakes the sky blue at night

 

So many.......must resist......

 

ATTACK!!!!



jk - we have to play nice ‘round these parts.