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Discussion Starter #1
I've noticed not being able to turn my fog lights on without the low beams being on kind of defeates the purpose of having fog lights to begin with, and after searching online for a mod where I can switch my fog lights on and off with just my parking lights being on, and failing, I decided to just do it myself. While this doesn't make the fog lights FULLY independent, it's better than the stock setting. So, here ya go. Sorry in advance for the crappy iPhone photos.

In essence, all you're doing here is bypassing the BCM. You're taking the green wire and splicing it to the orange wire with a jumper (my red wire). Here's the wiring diagram:


Tools required:
Wire strippers
Crimps, if using butt splice connectors
Electrical Tape
10-12" of copper wire used for a jumper (Any color, I used red)
Philips tip screwdriver
(2) Wire nuts or (2) butt splice connectors (recommended)
10 mm socket or nut driver (optional)

Step 1: Remove driver's side scuff plate and cowl


Step 2: Pull out the hood release switch and the screw sitting just behind it



Step 3: Pull the lower trim panel forward and try to place it out of the way--without warping or breaking it. The red arrow in the picture below shows where you'll be working, unfortunately. You can use the 10 mm socket or nut driver to release the fuse block and pull it out of the way if it's a bother.


Step 4: Look into the work area, and you'll find the BCM (pictured below). Also in the picture, you'll see two arrows pointing to two different wire harnesses. Carefully pull these two harnesses out of the BCM (by NOT pulling on the wires)


Step 5: On the gray harness (the top one), find the pictured green wire. Cut about 1" to 1 1/2" from the connector. Tape the end of the short wire with electrical tape and strip the end of the now-free longer green wire.


Step 6: Take your 10-12" jumper wire and splice it to the green wire you stripped. I used a wire nut as this was when I was still testing it, but I prefer (and plan to replace with) a butt splice connector.



Step 7: Now take your blue wire harness, locate the orange wire on the end (beside the blue wire, below the brown wire--pictures below). Cut about 1" to 1 1/2" from the connector. Tape the short wire with electrical tape, and strip the end of the longer, free orange wire.


Step 8: Take the free end of your jumper wire and splice it with the orange wire you just stripped.


Step 9: Plug the wire harnesses back in the correct spot. The gray harness goes to the top port on the BCM, and the blue harness connects into the bottom port. Use the picture above if confused or just don't trust my word.

Step 10: If you unbolted the fuse block to move it, put it back in place and bolt it in. Push the lower trim panel back where it belongs, insert the screw into the bottom where the hood release sits, and put the hood release back where it goes. Snap in the cowl and scuff plate.

Now we're done! :)
 

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Nice work and thanks for the tutorial! Quick question though... Does the fog light switch still work? As in can you turn them on and off still using the fog light switch?
 

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Discussion Starter #6
Nice work and thanks for the tutorial! Quick question though... Does the fog light switch still work? As in can you turn them on and off still using the fog light switch?
Yes the fog light switch still turns it on/off if you have your parking lights or headlights on.
 

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Discussion Starter #7
Thanks for posting this. How does this work if u are using the auto headlights feature?
I don't have the auto headlight feature in my car, but I'm almost positive it will still work. The fog lights don't use the same circuit for the headlights, so you should be all set. However the fogs will still turn off if your parking lights turn off
 

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2010 MZ3
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144 Posts
For those who doesn't want to cut and splice wires here's how:

After removing the plugs from the BCM lift the white plastic lock on the plug


Then wedge a small flat head screw driver (shown on the pic below) to release the lock of connector plug to the wire


Then the pull the wire out
 

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Nice job
I did make a thread i think on torontomazda3 about indy fog mod on the 2010 and up models a LOOOOONG time ago. It is much more work involved then yours. The fog relay is in behind the washer fluid reservoir on the passenger side. The orange wire and if i remember correctly the green wire on the relay needed to be rerouted back inside the cabin for power and connection to the switch.
 

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Seriously want to do this. This drove me insane when I first took ownership of the car, as with my last truck I ran my own fogs and ALWAYS ran with my Ambers on every time I started the truck. I think ill be doing this but pull the plug wire out and use a jumper so that IF ...IF I need to take it to Mazda I can just toss it back & save the speech and warranty.

Thanks for the write up! I miss the crap tons of write ups for my Xterra, cant seem to find many people who do much modding other then the usual exterior "show off mods"..
 

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ME - UTSA
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Thanks for the write up i had this on my truck and found it obnoxious that this wasnt a factory setting. Thanks for the info ill be doing this mod over the upcoming weekend
 

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So basically for not cutting wires. I just pull out the green wire from white conn. And the orange from the blue conn. And join those to together without the extra red wire he used right?

Sent from my DROID RAZR
 

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I just did this!!!!!:yes: although i had to cut the two wires :sad 1: I wasnt able to get the wires free from the connector. But all is well and the lights work as expected. :walkman: Tomorrow i may go back in and soder the wires together for a much cleaner look.
 

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So Far So Good
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Good to know!

Does fog still turns off when turning on high beam with this mod?

Mine as DRLs, will this work too?
 

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This was exactly how I wanted my fog lights to work! Thank you rope612 for the 'how to'. They work great! The only thing I did different was use posi-locks to connect the jumper which seem to work real well also.
 
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