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fog light question

8K views 11 replies 8 participants last post by  shakin 
#1 ·
my stock 02 didnt come with foglights, and i would really like to do it.

ive read a ton of the posts regarding fogs, but i still have a few unanswered questions before i get my hands dirty.

if i bought a set of used foglights like these off ebay, that had the housing. And i buy brackets ($36 shipped ebay) where do i find a full harness to run/tap into my low beam headlights?
http://cgi.ebay.com/ebaymotors/Used...008QQitemZ180213030109QQrdZ1QQsspagenameZWDVW

ive gotten this down:
cut the hole in the bumper w/ dremel
bolt up foglights w/ bracket

but i dont know at all what i need as far as wiring is conerned. i want to install HIDs in my fogs too.. but first things first, i would really like to know where i can get the full harness or how to modify a harness so that when i turn on my headlights, my fogs automatically turn on.

i really do not want a seperate switch for the fogs.
 
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#2 ·
you can buy any universal fog light wireing harness and run it to the dash where the fog light switch would be if u did have them which is next to the head light switch. of you could tap into the low beams which i wouldnt recommend. running the wires are really easy
 
#3 ·
this should help

i found this in the articles section of the site there are pics there too that may help..
Step 13) Now that we've installed the fog lights between the bumper and the frame, we have to wire them up. There are several options:

First, you could wire them to any of the lights already present in the front with a relay.

Second, you could utilize the fog light relay and fuse that are already in the fuse box under the hood.

Third, you could pull wires through the firewall.

Option 1 is definately the easiest. All you have to do is add a T-tap to the correct wire, in our case we connected the fog light control to the (+) low beam. Then connect this T-tap to the coil on the relay and ground the other side. At this point you would need power for the fog lights which will be switched by the relay that was just described. The fusebox under the hood has a simple spot where you can simply add a ring with a wire to connect to battery (+). In this wire I suggest you add fuses. We used a 20amp fuse. Now the second wire you need is ground. You could connect this to the frame or the battery itself. Make sure that you can get a good contact and always test the ground after you install it with a multi-meter. This method allows you to have the fog lights automatically come on with the low beams.

Option 2 is a bit harder, however this would allow you to make it look more stock. You can solder on the bottom of the fuse box the wiring for the fog lights, everything should be present except for the wiring harness to the fog lights. After you've connected the fog lights to the fuse box you have several options for how to control them. At the BCM you could connect the foglight relay control with the lowbeam relay control, this would essentially work the same as method one, except you connect the lowbeams and foglights at the BCM. The other option is that you buy the stock headlight switch with fog light control. This will not work straight out of the box, to have it work completely OEM the dealership has to reprogram the BCM so that it will interpret the fog light signal and switch the foglight relay control accordingly. However, one could just cut the foglight relay control @ the BCM and T-tap it to the foglight control signal. This way the BCM does not have to be reprogrammed, plus the fog lights will then not turn off when you turn your high beams on. If you do want your fog lights to turn off when your highbeams turn on, just add a relay and connect the relay's coil to the high beam relay control.

Option 3 is very similar to the first option, except instead of using a light signal, we pull 1 or 2 wires through the firewall and put a switch behind it, this will look the least OEM of them all. You can however, get the OEM light switch with fog light control and wire the fog light signal to a relay to control them behind the dash and pull the wires for this through the firewall. This would work the same as the second option, this way you don't have to mess with the wiring at the BCM. However, this way you do have to pull 1 or 2 wires through the firewall.

We wired the foglights to the lowbeams as described in the first option. Here is a quick overview / diagram of how we need to wire it up:





This is a quick overview of how we need to wire the headlights. You have to connect the right foglights (left in the picture) to the left side of the car (right in the picture). We did this by guiding the wire up to the right headlight (left in the picture) and then guiding wire along the existing light wiring harness it through the tube right behind/below the grill to the left side of the car (right in the picture). The left foglight is pulled up the headlight wiring on the left (right in the picture). Both of these foglights are then spliced together and connected at a relay. This relay is switched via the low beam signal which inturn can connect the battery (+) to the foglights when the lowbeams are on. The ground is always connected. For the lowbeam signal, check the wires on the connector on the headlights and test with a multimeter which is the lowbeam signal wire



Above, you can see the right foglight wiring going up to the headlight wiring where it is guided through a tube that was already present to the other side.



At the left headlight connector we connected a green wire to the lowbeam signal, we then connected this to the connector allowing us to disable the fog lights if needed simply by disconnecting this connector. (You can see this connector right above the left headlight connector). This signal then leads to the coil on the relay and the other side is connected to ground (leads off to the right along with the batt(+) between the fender and the battery to the fusebox under the hood. The left and right foglights are spliced together and are connected directly to ground and the other side is connected to the switched battery(+) on the relay.



This is between the battery and the fusebox under the hood. You can see where the wire connects to the battery (+) under the fusebox cover, and the ground connects to the bolt against the fender.

-Source: ewoutvb.com






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#5 ·
yay

i just bought a set of foglights w/ brackets off a member for $60.

i just need a harness.. so ANY universal harness works eh. i think i will just install an aftermarket switch, it seems the most popular and easy.

what bulbs do the foglights use? 9006 is what i heard from another member once before. would i just buy a harness, and wire in the "9006" plug.

anyone have an input on installing HIDs with fogs? or should i just use a standard bulb

regardless... im getting fogs! :hail:
 
#8 ·
what bulbs do the foglights use? 9006 is what i heard from another member once before. would i just buy a harness, and wire in the "9006" plug.

anyone have an input on installing HIDs with fogs? or should i just use a standard bulb

regardless... im getting fogs! :hail:
The Fog lights are an 880 bulb. I think I got the harness from NAPA (they had to order it)
 
#6 ·
I have to say.. I like the idea of using Option 2 with a stock switch with fog light controls.. and the ability to run high beams AND the fogs at the same time is nice as well..
 
#7 ·
When I installed mine, I used two relays to make the fogs behave like they were from the factory but without reprogramming the computer. First, I hooked them up exactly like gearjamminjake describes in option 1 to make a relay energize when the low beams are turned on. This will make the fog lights be on whenever the truck is in gear because the DRL's will energize the relay. This is not how fogs work from the factory so I didn't want that so I added a second relay. Instead of the first relay being connected to the fogs, they are connected to pin 87 of a second relay. This relay has pin 85 to ground and 30 to the fogs. I hooked the parking light wire to pin 86. So for the fogs to turn on, both the parking lights and the low beams have to be on at the same time. So the fogs are not on with the DRLs or with the high beams, just like factory. I hope this wasn't confusing.
Shaun
 
#9 ·
Could someone please post a pic or link of the brackets? I thought that the OEM fog lights mounted directly to the back of the front bumper cover on factory equipped vehicles, and if you wanted to install them into a non-equipped bumper you had to make your own mounts.:confused:
 
#11 ·
If I only wired to the parking lights, then the fogs would not turn off when the high beams were selected. Now some prefer their fogs to be on with high and low beams, but I was going for factory operation. Also, they flashed when I armed and disarmed my alarm and remote started the trailblazer. I did not like this.
 
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