ND4's Fog Light Anytime Mod... NO splicing, No Bending, 100% reversible

Back story:

Well as we all know, there are various ways to do the fog light any time mod, from splicing to some wire in the main harness and having to bend one of the legs of the fog light relay etc etc.

I didnt like any of that for the very reason i could not go back to 100% stock. I didnt want to bend the leg on the relay and i didnt want to splice into the harness... why? Truck is brand new and if i wanted to take her into the dealer i wanted to be able to put it 100% back to stock without having to buy a second non bent factory relay. So i got to thinking and took some ideas from some other variants on the fog light anytime mod and came up with this described below... truth be told im surprised no one has done this before.
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ACTUAL MOD:

Essentially i created 4 extensions with some male and female blade crimp connectors.

3 of these extensions go back into the original socket where the fog light relay went, colors are of the wires i used to extend the harness:

• (GREEN) the switched ground thats activated by the switch in the dash
• (WHITE) constant 12v from battery
• (YELLOW) Switched 12v to the fog lights

The last extension (BROWN) goes to a switched on ignition 12v hot, this can be pulled from many places, But its exceptionally easy to grab it from the big AC relay for the dc-ac inverter... its EVEN EASIER on the tacomas (mine is a 13 DCSB TRD OR) which have the external small relay box which just so happens to have the Fog light relay and AC inverter relay.
(See here for which hole the bent pin goes into -> https://www.tacomaworld.com/threads...g-100-reversible.309407/page-27#post-10852290)



Simply make the extension with a thin blade connector and bend it so the barrel part of the crimp connector clears the relay. And walla... done, fog lights that you can turn on any time the key is in the on position regardless of what light mode you are in, fog lights that turn off with the key, AND fog lights that dont randomly turn on for a minute every 4 hours for some test procedure.

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Modifications / Variations on the original Mod

• If your fog relay is not in the AC/DC box check here and use the horn relay - https://www.tacomaworld.com/threads...g-100-reversible.309407/page-39#post-18445182
• If you do not have a dc-ac converter relay, check post 15 for an alternate source for a switched 12v
• If you want the fogs to turn on / off when switched to headlights regardless of high or low beam, check post 39 for the variation
• Check here for the super stealth way to do this mod!!!

Notes:

• A standard width blade connector will not fit into the stock ground socket (green wire to relay box), simply take a pair of snips and chop off some width of the connector. The main power (white) and (yellow) are full width and you will have no issues.
• The AC-DC inverter relay works in an interesting way, You can use my pictures below to see which leg you need to pull off of for a truck with the external relay box, but if you are doing this mod on a truck where the fog light / ac-dc inverter relay is in the main fuse box double check which one is actually the switched 12v on ignition for the dc-ac relay. Reason i say this is, with the key off both of the legs of the relay that operate the switch of the relay will read 0 volts, put the key in and turn it on both of the legs will read 12v (wtf?!?! you might say), Press the ac-dc inverter switch on the dash and one of those legs drops to 0 volts and switches the relay on... YOU DO NOT want the leg that drops to 0 when the dash button is pressed... you want the leg that goes to 12v when the key is on and stays at 12v when the ac-dc inverter is pressed.
• No extra inline fuses are necessary... they would be pointless as everything is already fused to begin with. This will not blow any fuses as the extra draw from the hot from the ac-dc relay is probably less than a TENTH of an amp.
• For a picture of how the bent male blade connector is placed in the relay socket see the first attached picture in post 15

All in all it took about 4x as long to write up this thread compared to actually doing the mod.

• 1st pic is showing where the wires are going
• 2nd pic shows how the male blade connector is bent so it will fit in the proper socket along with the AC-DC relay
• 3 pic shows the relay tucked away in its new home.

 

Sub'd.
Looks good

 

I gotta say, that looks much better than the threads I read about this mod.

This mod and your method is now on my list of things to do. Thanks!

+ Rep

**EDIT** What gauge wire did you use??

 

Good job OP!

 

Great job, much cleaner and I like it is easy to reverse. I will be doing this mod soon.

 

Note: The switched 12v pulled off the DC-AC inverter relay will not work on the SR5 / Base models... as well there is no inverter and thus no relay... Though however they MIGHT be the wiring to the relay box / fuse box that you could still plug into... i would look but i do not have a base / sr5 at my disposal to look at.


Hell... do the base / sr5's even have fog lights?

 

Gonna have to do this one of these days

 

The SR5s do have fog lights. I am sure there is switched 12v close by.

 

ok then... id imagine one of the ignition relays could be used in place of the AC relay.

Ill do some probing with the multimeter tomorrow for an alternative switched 12v source thats as easy as the ac relay.

 

That's perfect! Sub'd for next scheduled wiring day.

 

My base model didn't have fogs, but was pre wired. I just installed lamps, relay and switch.

If you find another 12v switched nearby, I would like to know. I like the idea of this no splice mod.

 

Does it also have the wires in the socket for the dc-ac relay?

 

Used some quality 16awg wire. You don't need anything too big as its a very short run and the fogs are not the biggest draw. The green and brown wires you could do like 24 awg as there is hardly any draw on them.

 

For those without the DC-AC inverter relay or wanting another switched on ignition 12v source here is another one.

The EFI relay.

It switches a constant 12v from the battery when you turn the key to ON. just what we want. See pics below on which one is the one you are grabbing power from for an idea.

So you could pull power from here and route the BROWN wire in my original post from the fog light relay to this location and the function of the fog lights would be the same (fog light any time).

Observations and notes:

• It seems as though this power source stays on 5 seconds or so after the ignition is turned off (likely to properly power down all the efi equipment properly). This it not a big deal just something i noticed.
• I can not say if this relay is ALWAYS off when the key is out and truck is turned off. I doubt it turns on with the truck just sitting there, but you never know, if at most it will be for a minute every 4 hours or something for some diagnostic like in one of the other splice foglight mods variants.
• The location pictured below is from the fuse box of a 2013 TRD off road v6 dcsb auto... your fuse box might be laid out differently and its possible that the constant hot is flip flopped from the switched hot you need (inner and outer main relay legs)... simply take a multimeter to double check.

First pic showing where i tapped in for the switched 12v with a test lead, second pic showing relay installed.

 

I will do this when the weather clears up.

 

Great job op, sub for future mod.

 

There's also the option in my sig that is 100% reversible, looks stock and it's free.

 

Sub'd

 

Neat. I like this way better than the current way of doing it with the stupid splice.

Ill have to change mine to this.

:beer:

 

Great write up.

What all would someone need to do this? Crimpers, 16g wire, thin male blade connectors and anything else? Or would that be it. Thanks!