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badblu97

The fog light mod is bogus and doesn't work. They never got it working, it is a theoretical mod. I wasted weekend trying to get to work and here is why, from the service manual:

Fog Lamps

With both the ignition switch in the RUN position, and the park lamps ON, the fog lights will illuminate when the driver depresses the fog lamp switch. The BCM receives the park lamp ON signal from the interior park lamps supply voltage signal circuit. With the headlamp switch in either the park or headlamp position, and the fog lamp switch is in the ON position, the BCM will ground the fog lamp relay control circuit causing the relay to energize. The current flows from the fog lamp relay to both front fog lamps. The state of the fog lamps will remain the same until the fog lamp switch position is changed, or the ignition switch is cycled OFF and ON. Fog lamp operation will be cancelled whenever the park lamps are turned OFF or the high beam headlights have been selected.
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I ran power to one purple wire and the park lights came on and the other purple wire nothing happened.
 

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The BCM is the only thing controlling the fogs, through the fog relay, by grounding it. If you ground that relay at any time, your fogs will come on. So you can have anything turn on your fogs at anytime by grounding that one pin under the relay: when ignition is on, when headlights are on, when DRL is on.... anytime. No need to lift the fusebox and tap any wires. Shove a wire into pin85 on the fog relay and anytime that wire is grounded, they click on using the factory foglight wiring (your ground is only clicking on a relay so there is almost no load, no need to worry about overheating a wire)/
 

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Whoa! I could really use a diagram or a pic or something! I got confused just reading that! (maybe bc I just worked 12 hours lol) thanx for the info! I really just want to use my fogs as DRLs, could you explain how to wire it?
 

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I have my DRLs rewired to my fog lights....

It doesn't matter what position my fog light switch is in either. I currently have it in the off position.
 

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What you need:
-a wire stuck into pin 85 of your foglight relay
-the other end of that wire to be ground when your DRL should be on

This will click on your fog relay during a DRL, using the factory foglight wiring.

First, you need a wire. Any wire will do, the only load on the wire is to click on a relay so it will carry almost no current/load. Splice a lot of exposed wire on one end, pull your foglight relay, look at the bottom of the relay for pin 85. Stick the wire into the hole for pin 85 and shove the relay back in, holding the wire in as well. You want enough exposed wire to get in the pin without touching any of the other pins. Now anytime you put ground on the other end of the wire, the fog relay will click on turning on the foglights.


Second, you need a ground only when the BCM is trying to turn on your DRLs. There is an easy way or a hard way. The easy way is to disable the DRL turning on your headlights and using the DRL fuse in the underhood fusebox to get ground during a DRL. So your fogs will be DRL but not your headlights. The hard way is to have the headlight DRL still work and also the fogs. The hard way you will have to get the ground from the DRL relay in the cockpit fusebox OR from the BCM wire itself, and run that wire to the underhood fusebox. Let me know if you want BOTH on, but if you want to replace the headlight DRL with foglight DRL, here is the easy way:

Remove the DRL fuse from the underhood fusebox. Now you have two exposed pins. One side of that fuse goes to the DRL relay in the cockpit and the BCM's ground signal, the other side of the fuse is always 12v. Use a mutltimeter or a 12v light to test which pin has 12V. Once you know which is 12v, you want the OTHER pin. Take the fuse and cut it in half with cutting pliers. Throw one half away, and use the other half the stick the other end of the wire going to your foglight relay into the non-12v pin of the DRL fuse, and stick the half a fuse in to hold the wire in place.

Now the DRL fuse is cut so your headlights wont come on, and the wire from the half a fuse will ground when the BCM wants to turn on the DRL relay, but instead it will click on the foglight relay.

Let me know how it turns out.

The only problem I can think of you might having, is that the underhood fusebox uses the tiny mini fuses and that might not be enough to hold that ground wire in on the DRL fuse. To make it stick better instead of cutting the fuse in half put 12v and ground on the fuse to BLOW the fuse and then stick it in to hold thet wire, then it will have two pins holding it in but since the fuse it blown the DRL relay wont matter.
 

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Your da-man! I've been wanting to install halos also as my drls. thank you great job
 

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Going thru TurboMikes instructions above, I don't see a DRL fuse in the underhood fuse block...what am I missing...other than a clue....


Sent from AutoGuide.com App
 

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My bad: DRL fuse is in the cockpit fuse box. You'll need to run the wire through the firewall hole behind the glove box to the underhood fusebox. Less fun doing this mod.
 

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Unless you can figure out where the wire from the DRL fuse taps into the headlight wires under the hood. Might be under the fusebox. Wont have access to my shop manuals for a few days.
 

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No worries, Thanks for the info. There is the DRL relay in the cockpit fusebox two (not sure why two?), I wonder if I can do your mod from there all inside?


Sent from AutoGuide.com App
 

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Just finished my DRL Re-Route. This is a direct message to those who questioned weither or not it was possible to run the DRL's to the parking lights, it very much is. and even better than that, I installed my flashback LED turn signals, so now I have HID 55W Low beams (on at night) 35w HID high beams (only when I turn them on) normal amber turn signals and markers when lock and unlock, and LED white DRL's during the day. I was said all told, with all the HID's and LED's and accessories. 200 bucks tops, and thats on the high end, please let me know if you want any help wiring, I would be happy to help!! Thanks for all the help on this thread as well.
 

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Been this way since 2009. Works great.

Just finished my DRL Re-Route. This is a direct message to those who questioned weither or not it was possible to run the DRL's to the parking lights, it very much is. and even better than that, I installed my flashback LED turn signals, so now I have HID 55W Low beams (on at night) 35w HID high beams (only when I turn them on) normal amber turn signals and markers when lock and unlock, and LED white DRL's during the day. I was said all told, with all the HID's and LED's and accessories. 200 bucks tops, and thats on the high end, please let me know if you want any help wiring, I would be happy to help!! Thanks for all the help on this thread as well.
 

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I'm not gonna read through all the post but who said this didn't work?


What I will tell you is that the wiring harness on a 08 is different from 09 and 09.5. I found out the hard way. Cut the regular yellow cable as I have for a few guys, go to start the car, no bueno. Resolder the wire, and the car started. Never assume, it just made an A$$ out of me.

Follow the directions on page 1, and tap into the passenger side green wire going into the fog light.
 

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Quick question, if I just want to shut the DRL's off and retain auto on functionality.

Can I cut the Yellow wire, as shown in the first post and tape both ends? (08 GT)
 

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Why would you want to do that? You cut that and tape it off it will do the same as just pulling the DRL fuse which is a hell of a lot less risky.

You will still have auto on functionality if you pull the DRL fuse.
Don't mess with the fuse box unless you are rerouting.

Besides, as I mentioned previously, you cut that "wire" your car will not start since its an 08. I still am not sure which wire it is for 08 but I guarantee you its not the same.
 

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Why would you want to do that? You cut that and tape it off it will do the same as just pulling the DRL fuse which is a hell of a lot less risky.

You will still have auto on functionality if you pull the DRL fuse.
Don't mess with the fuse box unless you are rerouting.
My apologies, my understanding was that pulling the DRL fuse cut the auto function.

If it doesn't then it is the most efficient method, I really don't like DRL.
 

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My apologies, my understanding was that pulling the DRL fuse cut the auto function.

If it doesn't then it is the most efficient method, I really don't like DRL.
That is the most effective. Pull the fuse.. :) Driver side panel by your left leg, should be the labeled on the door.
 

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Just finished my DRL Re-Route. This is a direct message to those who questioned weither or not it was possible to run the DRL's to the parking lights, it very much is. and even better than that, I installed my flashback LED turn signals, so now I have HID 55W Low beams (on at night) 35w HID high beams (only when I turn them on) normal amber turn signals and markers when lock and unlock, and LED white DRL's during the day. I was said all told, with all the HID's and LED's and accessories. 200 bucks tops, and thats on the high end, please let me know if you want any help wiring, I would be happy to help!! Thanks for all the help on this thread as well.
Reviving thread -

chamilton: currently, my lo-beams are set as the DRLs & my LED strips only turn on at night. I want to reverse that--make my LED strips on during the day, and my headlights turn on automatically only at night (will install a HID kit, don't want to use a relay harness, don't want to pull DRL fuse).

What is the easiest way to switch this? thanks!
 

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I assume your LED strips are getting power from the parking lights?

Headlights on only at night: do nothing, thats OEM setup

LED strips on with OEM DRL circuit: You need to disconnect the LED strips from getting power from your parking lights. Then pull the DRL fuse so your headlights dont come on with DRL. Then tap into the DRL relay and use the output from that to click on a relay that turns on your LED strips.

If you know what you're doing, buy a 12v relay and use the circuit diagrams in the shop manuals where to tap into the DRL circuit to power it. If you dont have them let me know I can look it up for you.
 
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