DIY: Fog Lights on with High Beams (Brights) FREE!

This is what I did with mine. They work with high or low beam so they can be dimmed with the hi/lo switch.
https://www.tacomaworld.com/threads/high-or-low-beam-switch-for-fog-lights.531061/

 

Just did this today after finding this post! First mod on my new to me 2005 Taco TRD OR.

 

Resurrecting this to ask if it works on a third gen?

 

Performed this modification today. Easy solder. Exact functionality I was looking for. Thanks OP!

 

Worked like a charm for my 2013 SR5 w/fogs.

I used a large gauge paper clip and wrapped it tightly around the posts.

 

just an FYI - i dont know if this affects all 2nd gens, but on my 14 all this is doing is forcing the low beams on constantly (when the headlight switch is turned on). this means that both high and low elements are on in the dual filament bulb. and obviously the fog lights are on if you have the fog switch on.

you guys keep saying that it only keeps the fogs on. this is 100% false on my 2014 model. this mod forces the low beam relay to stay "picked up" whenever the headlight switch is on. so when you hit your high beams, the low beam relay is still active. since the lows are active, the fogs still work

 

Since this thread popped back up given its 2012 beginning, a comment. When threads cover so many years of models "things " do change over time. Remember that the first couple of year (05-06) 2nd gens did not have DTR. I wanted to use my Fogs as DTR and have for many years on an '06. The parking lights are not nearly bright enough to be effective DTR. I have only changed out the fog bulbs once and most likely because they aged out not from over use. The jumper wire in the fuse box anytime mod, not this mod, has allowed complete control of the fogs on an early 2nd gen (fogs on, Hi/Lo off). Just a comment on the passage of time and subtle change, not this mod.

 

yeah that’s the way I’m taking this mod so I’m confused on how I should go about my situation. My 09 has Alpharex headlights and the lows already stay on with the high beams. I just want my fogs to stay on when I switch to high beams.

 

So ONE of these mods (the original post?) essentially changes nothing about fogs on with low beams, but adds high beam into the mix when flipped on? So you’re adding the high beam to the low beam + fog. Is that correct?
The way I read the OP it was only to keep the fogs on along with high OR low beam. To me that makes more sense to do… if I’m on an empty road I just turn on the LED bar in my grill. Idk why I’d want high and low on together.
But I’d be interested if the mod keeps high and low separate but keeps fogs on with either.

 

WORD!
I need the Fog Lights on with High beams “for dummies” edition.

 

Alright, so I'm trying to understand this mod fully. Some folks have complained that doing this will keep the low beams energized when the high beams are on (both filaments burning) and I think I see their point.

For reference, I'm referring to standard relay terminal numbers:



In this convention 85 and 86 are the two sides of the "coil" which powers the relay.

The 30 terminal is the "common" terminal that is always used.

The 87 terminal is the "normally open" terminal which will not be connected to the 30 "common" terminal unless power is applied to the coil.

The 87a terminal is the "normally closed" terminal which will be connected to the 30 "common" terminal until power is applied to the coil.

The relay you are modifying is not the relay for the fog lights itself, it's the relay for the dimmer switch (labeled as "DIM".)

On this "DIM" relay, you are shorting the 87a relay terminal (normally closed) to the 30 relay terminal (common).

Per the wiring diagram, the 87a terminal (labeled as "4" on the diagram) is what feeds power to the relay that controls the fog lights. In factory form, if the coil on the "DIM" relay is not energized, then power will flow from the 30 terminal (common, labeled as "3" on the wiring diagram) to the 87a terminal (normally closed) powering the low beam and also the coil of the fog light relay. If the coil on the "DIM" relay is energized, then power will flow from the "common" 30 terminal to the 87 terminal (normally open, labeled as "5" on the wiring diagram) powering the high beam, but removing power from the coil of the fog light relay.

So put simply: in stock form, you get either power to the high beam or the low beam. Not both at the same time. And power to the low beam energizes the fog light relay.

By modifying the "DIM" relay as you have, you can either power the low beam or the low beam and high beam at the same time.

While this may be desirable for some, it will have a deleterious effect on bulb life and doesn't meet the stated goal of enabling fog lights with the high beams without altering the functionality in any other way.

I believe the way you truly achieve that goal is to power the coil on the "FOG" relay using the power output on the "HEAD" relay, bypassing the "DIM" relay entirely. Doing this will require some wiring of course, but won't kill your bulbs.