Wiring Aux. Lights into Stock Fog Lights

marks10cc · Post by **marks10cc** » Fri Nov 14, 2003 2:24 pm

I have been searching for two days, and many posts come close to answering my question, but never quite do it.

I don't have fog lights on my S-10. I missed them, so I bought a pair from autozone, nothing special just some white beams. It came with a switch and a relay, but I don't want to follow their directions. They want me to tap the battery twice... once for the switch (3A fuse) and once for the lights (25A fuse). It's a simple set up...

Switch:
+ Power to switch from battery with inline fuse.
- Power to switch from a 'good ground'
A Activate line from switch to relay 85?

Relay:
85 Activate + from switch
86 a 'good ground'
30 12v + inline fused from battery
87 12v + to the foglights

Lights:
+ 12v line from the realy
- power to a 'good ground'

I have some problems with this setup, and was wondering if you guys could help me tap into the already wired fog light options within the truck. I noticed the interior fuse box has a slot marked 'fog light'. So I'm guessing that all of the wiring is there for these already, and just the lights, switch, and relay are needed.

First, the lights will work without the ignition... don't want that. I want these lights to only work with the ignition, even better, only with the head lights. If I run the + switch line from the 'fog light' interior fuse box location, will it solve this?

Second, the lights will not be protected by the auto-saver shut off feature (more like the battery won't be protected). Where do the stock fog lights receive their 12v power from? Is there a wire somewhere I can use as my 12v relay power source that is tied in with this?

I find it hard to believe that the wiring harness changes between fog and non-fog trucks. It's just installing the lenses with the fogs and running a few wires, right? (hope)

On a seperate note... anyone know where I can get a stock light control bezel and GM fog light switch? Not many junkyards around here that admit they have s-series parts.

MikeyZR5 · Post by **MikeyZR5** » Fri Nov 14, 2003 3:35 pm

I thought I saw one on Ebay....But i might be wrong.

adrenalnjunky · Post by **adrenalnjunky** » Fri Nov 14, 2003 4:47 pm

Hmm--I wish i could draw it out for you -- I bee designing relay setups for 2 days for the lighting systems on my truck.

The difficult part was that I want the set I'm mounting under the rear bump er to light up ANY time that I put the truck in reverse, and also independly of that from a switch in the dash (AKA -- the no tailgater switch). Just takes 2 relays to do, and they have to be wired together -- but it's easily enough done.

Let me think about what you're wanting to do and I'll have a response a lil later.

Post by **HenryJ** » Fri Nov 14, 2003 4:54 pm

If you can not find a light switch panel with fog switch , email Kelly or Joe at http://www.northverdeautosalvage.com, tell them Brule sent you and you want a really good price. They will find one if they don't have one already.

The stock fogs are controlled by the BCM (Bi-polar latching relay activated by the momentary switch) and are only active when lowbeams are used (no the quad mod didn't fix that

) If you are wanting to use them as driving lights I'd recommend using a different method of activation.

I used the rear wiper/hatch switch for my aux. fog lights

The hatch release is for the fuel transfer , lift the upper switch once for the aux. fogs, second upper position will be for the driving lights with the fogs, and the upper wiper switch for the aux. back-up lights.

That one switch($15 used) can control four functions.

Another option is to just install your own switch in the panel and use the supplied wiper/hatch wiring for your switch as AZS10crew did here: Wiring Question

adrenalnjunky · Post by **adrenalnjunky** » Fri Nov 14, 2003 4:56 pm

Question -- when you say you only want them to work withthe headlamps on, do you use your Automatic Headlamp feature? The only reason I ask is that it's possible to have the headlamps on without the ignition on if you don't use the AHL.

If you are like me, I just let the truck turn my lights on and off, and in that case, the Ignition does have to be on.

adrenalnjunky · Post by **adrenalnjunky** » Fri Nov 14, 2003 5:38 pm

Ok -- here's relay situation #1. Of course this is using all your own wiring and none of the factory -- which personally I prefer, but that's just me. with this setup, your Foglights would only turn on when:

A) Your switch in the cab is turned on.

B) Your Headlights are on.

There are some decisions you will have to make:

If you wire it this way, Your fogs will only run when either your high beams are on, or your low beams are on depending on which Headlamp 12V you use as a trigger. (Unless you have done the quad beam mod already).

My dad wired his truck this way to the low beams because he wanted the fog lamps to turn off whenever he turned the highbeams on. (That is actually the correct way to use fog lamps anyhow.)

If you want your lights to run either with Highbeams or low beams, then it would be easier to use the Parking lamp 12V as your trigger. Plus then you don't run the chance that your DRL's could allow your Fogs to run during the daytime.

Post by **HenryJ** » Fri Nov 14, 2003 5:54 pm

adrenalnjunky wrote:Ok -- here's relay situation #1. Of course this is using all your own wiring and none of the factory -- which personally I prefer, but that's just me. with this setup, your Foglights would only turn on when:
A) Your switch in the cab is turned on.
B) Your Headlights are on.
image

I have a question on wiring using this method: What headlight wire are you planning to use a power source for your relay?

There is no dedicated "+" or "-". it changes with the activation source (ie. AHL or switch (that's why I tapped both for the quad mod)) and throw the DRL in there and you have a real confusing situation.

I'm sure it can be done, maybe you could get the color code of the wire to be tapped and color code your diagram?

(Just trying to make it easier for the person trying this

)

adrenalnjunky · Post by **adrenalnjunky** » Fri Nov 14, 2003 6:22 pm

Henry - It would depend -- It would have to be whichever wire is +12V when the lamp is on.

there are too many variables actually depending on what he's wanting to do :
fogs on with only Low beams
Fogs on with only high Beams
Fogs on with either.

And I'm not sure about the DRLS - since they run the Low beams at half power - I think--not 100% sure on that.

Personally -- since his only stipulation was that they turn on when healamps turn on, and turn off when they turn off, or if the Battery saver feature turns them off -- I would use the parking lamp 12V as the trigger and have the fogs run that way.

I had modified the fogs in my Z24 to run that way - never had any problems with it.

I'll try to do some probing and color code work this weekend.

Post by **HenryJ** » Fri Nov 14, 2003 6:37 pm

adrenalnjunky wrote:Henry - It would depend -- It would have to be whichever wire is +12V when the lamp is on.

Yea, "there lies the problem" one wire is "+" when activated by the AHL , the same wire is "-" when the light switch is used and the AHL is disabled.

It might be best to revise your diagram to use/tap both wires used to light a headlamp, that way when the pos. and neg. rotate it doesn't affect the function?

marks10cc · Post by **marks10cc** » Fri Nov 14, 2003 10:41 pm

I would like to work like most stock fogs do. Ignition and low beams have to be on for the fogs to activate (if the switch is on, of course). It would really be nice if they shut off when the high beams come on (even with the quadbeam mod which I just got done doing). So could I tap into the BCM? Or is that more headache than it's worth. BTW, after reading everying above... I came up with a make shift idea, but I'd like to know more about the BCM and if the fog light wiring is already in place behind the dome light area. It would be nice to install the factor looking switch, but that can come later.

Anyway... my idea from everyone's input for a temporary solution.

Tap into the rear wiper harness. Use the left yellow for power to the switch, the right most black for ground to the switch. Use the blue wire that came with the switch and run it from the cab to the engine bay, attach it to the relay and then wire up the relay as normal (blue wire + activate, good ground negative activiate, tap battery for +12, run out of relay to fogs).

If I read correctly, that yellow wire is an accessory power source, meaning the key has to be in accessory or run for power to get to it... and would also be subject to battery run-down protection. So, 2 birds down, one to go

But to answer questions....

Fog lights on when:
Vehicle has key
Parking lights are on
High beams are off

Fog lights off when:
No key
No lights
High beams are on

Thanks for input guys, maybe I have enough to at least get them wired this weekend.... now I just got to find a place to mount them

Post by **HenryJ** » Sat Nov 15, 2003 8:46 am

I think Adrenalnjunky has the right idea , but here's another thought on it.

How about just using the one relay and finding a wire in the lowbeam circuit that grounds when the lows come on?

I know that using the same yellow wire that is grounded for the quad mod would accomplish this , however then they would be available to be on with the high beams.

While you're checking wires check for another low beam wire that is grounded and tap it for your relay ground.

Pauleo · Post by **Pauleo** » Thu Dec 30, 2004 12:04 pm

I Know this topic is a year old, but after all this time, I STILL can't figure ouyt what the heck you guys are talking about! I know, I'M SLOW!!!! I want to do the same thing as markss10cc. The only thing I'm really concerned about is that I don't want to have to shut the fogs off after I take the key out. (I'm soooo sick of pulling in my garage, shutting off the truck & getting out. On;y to notice that i left my friggin fogs on again! Then I have to go back to the truck & switch them off. Maybe it's a pet peeve. I cal it a big PITA!!!!!) So can someone please tell me exactly what I need to do? BTW, I have an `01. I cut the pin off on the relay under the hood so I have no DRL's. AHL's still work though.

Also, I have my wires running thru my driver's side fender & into the door jamb. Then going in the fuse box. It's sooo ugly! I suck at this sort of thing! Where do I run the wires into the cab at? FYI: I am using the plastic "blank" next to the radio for my switch.

And I guess while I have your interest, where can I find fog or driving lights that will fill the space where the tow hooks go???? (My tow hooks are removed.)

Eric H · Post by **Eric H** » Thu Dec 30, 2004 12:18 pm

Pauleo wrote: Also, I have my wires running thru my driver's side fender & into the door jamb. Then going in the fuse box. It's sooo ugly! I suck at this sort of thing! Where do I run the wires into the cab at? FYI: I am using the plastic "blank" next to the radio for my switch.

Pull back the carpet on the passenger side right up by the firewall. (You might have to remove a kick panel too. Its been so long I don't remember if you have too...) You will see a gromit there with one wire going through it already. Just stretch the hole in the gromit and feed your wires through.

-Eric H

barch97 · Post by **barch97** » Thu Dec 30, 2004 12:32 pm

and switch to a power source that is activated with the ignition on.

Pauleo · Post by **Pauleo** » Thu Dec 30, 2004 1:05 pm

Right. I realize that I want a power source controlled by the ignition. My problem is what & where??? Also, if I use just any old source, then I may be driving around in the daytime with fogs from the night before. I need to tap into headlights somewhere I guess. Question is where???? I don't understand this whole reverse polarity thing with the AHL's. So what do I do guys???

And thanks Eric! I'll look for that gromet tonight. Maybe the same one that Best Buy used when they ran a power wire for my amp. I never thought of that till just now!

Post by **HenryJ** » Thu Dec 30, 2004 1:07 pm

Pauleo wrote:...I don't want to have to shut the fogs off after I take the key out. ...So can someone please tell me exactly what I need to do?...I am using the plastic "blank" next to the radio for my switch....Where do I run the wires into the cab at?

Install a relay under the hood where either of these are located-

Consult this thread for wiring codes - Wiring question Use Pin A yellow wire to power your switch. run a wire from the switch through the grommet at the top of the driverside foot well (Yes driverside! No need to go to the passengerside and back

) .
Pierce the boot with a test probe, then insert a long stiff wire through , bend the end of the wire 180* capturing the wire to pull through and route it to the relay pin 85 to activate the relay. Pin 30 is run to your fog lights. Pin 86 is grounded. Pin 87 is run to the accessory post in you power distribution center as described in this thread- Adding an accessory power source

where can I find fog or driving lights that will fill the space where the tow hooks go?

These are what I have mounted down there- Projector fog lights and Hella has some too

Post by **Walt** » Thu Dec 30, 2004 4:31 pm

Nice Winch Brule

I could've used it last week

Post by **HenryJ** » Thu Dec 30, 2004 5:15 pm

wamason wrote:Nice Winch Brule I could've used it last week

It is nice , Thanks! Hey if you're stranded in my neighborhood just holler...I'd be happy to loan it to you