DIY 2012 Civic Si Independent Fogs (picture heavy)

That could be the problem. Switch them around and see if the problem follows
 
So I'm kinda confused, how did you add that 15 amp fuse. Also with the fused ignition, is that being connected with the switch while while it also runs to the relay?
 
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Im finally getting around to doing this. Im just a little lost on where the wires are coming from or going to for the switch. I understand where to wire from the fuse box and where to tap the ignition. Just confused on the wiring between relay and switch, hopefully someone can please explain this a little better.

What is the purpose of the new relay in this situation? Are the fogs actually pulling power from the new relay since we removed the factory relay?
 
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Im finally getting around to doing this. Im just a little lost on where the wires are coming from or going to for the switch. I understand where to wire from the fuse box and where to tap the ignition. Just confused on the wiring between relay and switch, hopefully someone can please explain this a little better.

What is the purpose of the new relay in this situation? Are the fogs actually pulling power from the new relay since we removed the factory relay?
so you dont burn out ballasts with factory switchin you use aftermarket 40A relay with 30A fuse. Power comes independent, to switching relay and then from signal; wires from OEM headlamp control into relay to do the switching. Factory honda wiring can't candle proper current inrush for ballast, and hence people blow ballasts. (i've had the same bulbs and ballast since day one of my car) which has been 3 years on June 23rd
 
so you dont burn out ballasts with factory switchin you use aftermarket 40A relay with 30A fuse. Power comes independent, to switching relay and then from signal; wires from OEM headlamp control into relay to do the switching. Factory honda wiring can't candle proper current inrush for ballast, and hence people blow ballasts. (i've had the same bulbs and ballast since day one of my car) which has been 3 years on June 23rd

I understand how to wire the relay and switch, got that figured out. Only thing im confused about is how the OP is using the tapped ignition wire as his signal lead and power source lead for the new relay. I much rather be pulling power from the battery than the main ignition wire for the fog lights. If im not mistaken the new purple wire is the new power source to the fogs, just want to make sure i'm interpreting his diagram right?
 
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I understand how to wire the relay and switch, got that figured out. Only thing im confused about is how the OP is using the tapped ignition wire as his signal lead and power source lead for the new relay. I much rather be pulling power from the battery than the main ignition wire for the fog lights. If im not mistaken the new purple wire is the new power source to the fogs, just want to make sure i'm interpreting his diagram right?

Reason for me using the ignition wire is so if I ever forgot to shut the fogs off they would just shut off with the car.
 
Wanting to do the mod on my 2014 civic si sedan, I'm wanting to do the stalk method to keep factory switch as on and off, can I get some help in how to wire this, I read a forum on the 8th gen on splicing into the purple wire on stalk plug, then running a wire down to fog relay, cutting a orange one and connecting wire from stalk to other orange one which runs into relay, now I can't seem to fine the relay on my car, it looks like a different location then the 8thgen, I would like to be as simple as possible vs running new relay. Do u think I could splice purple wire and just run to a empty 12v fuse spot that's constant when cars on
 
I was thinking would it work if u was to just take the wire u added to fog relay and run it to a 12v switched in then same fuse box and just do a ad a fuse, that should keep factory switch intack and have independent control without getting under dash or splicing wires
 
Wanting to do the mod on my 2014 civic si sedan, I'm wanting to do the stalk method to keep factory switch as on and off, can I get some help in how to wire this, I read a forum on the 8th gen on splicing into the purple wire on stalk plug, then running a wire down to fog relay, cutting a orange one and connecting wire from stalk to other orange one which runs into relay, now I can't seem to fine the relay on my car, it looks like a different location then the 8thgen, I would like to be as simple as possible vs running new relay. Do u think I could splice purple wire and just run to a empty 12v fuse spot that's constant when cars on

I suspect that the part number 7 on this diagram is the wiring harness which interacts with the headlight/foglight stalk. The part number is 77901TR0A60 (for Sedan). If anyone can dig up an electrical diagram for this harness, I could figure out exactly how it needs to be modified. But otherwise, someone would have to figure out what each wire does using a multimeter. If I were dedicated to doing this mod, I would carefully take apart my steering wheel to expose this wiring harness (if necessary). Then I would find which wires are the switch input and output for the foglight switch. Then I would buy a new harness and modify it.
I'm personally not interested in doing any of this, because I'm not comfortable messing around with the steering wheel, with the airbag and all.
But yeah can anyone get electrical diagrams??
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Thanks for reply, well I actually just tried this today, the fuse box idea didn't work like I had hoped, so then I did take apart the steering wheel plastic covers and looked at the harness, I started to use a multimeter and tried to figure out what wire was what but I suspect that these are just low voltage trigger wires because when u switch on fogs back and forth at the relay trigger it wasn't reading much volts at all so I was worried that if I was to try and send 12 volts to this wire I would risk damaged so i decided to just go a head and add a hidden switch to turn them off and on, now just jammed a wire down into relay under the hood and ran the wire into the cab today, ran out of time, will finish tommorow, but I'm going to just run a switch only with a fuse from 12v ingnition, I won't run a new relay, don't see why I would need to? I will be running led fog projectors soon so no hids in my fogs so shouldn't have to worry about blowing ballast
 
Thanks for reply, well I actually just tried this today, the fuse box idea didn't work like I had hoped, so then I did take apart the steering wheel plastic covers and looked at the harness, I started to use a multimeter and tried to figure out what wire was what but I suspect that these are just low voltage trigger wires because when u switch on fogs back and forth at the relay trigger it wasn't reading much volts at all so I was worried that if I was to try and send 12 volts to this wire I would risk damaged so i decided to just go a head and add a hidden switch to turn them off and on, now just jammed a wire down into relay under the hood and ran the wire into the cab today, ran out of time, will finish tommorow, but I'm going to just run a switch only with a fuse from 12v ingnition, I won't run a new relay, don't see why I would need to? I will be running led fog projectors soon so no hids in my fogs so shouldn't have to worry about blowing ballast
How about posting instructions for taking apart the steering wheel, and I might take a look.
 
This si my first DIY so i apologize ahead of time!

You will need to purchase:
An external switch
A relay
Blue male spade
Yellow T-Tap
15AMP Fuse

First thing you want to do it locate the factory fog light relay. It is under the hood, on the right side of the engine bay.

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On the right side of the fuse box you will see the relays. You want the 5th fuse from the top, pull it out (to double check this is the correct fuse turn the fogs on and make sure they dont come on). Your going to use a male spade connector without the plastic to plug into where the power was fed by the factory relay. I used a 16 gauge wire.


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Drill a hole just big enough for the wire to fit on the side of the fuse box and feed the wire through. Your going to run this along the loomed wires on the outside of the fuse box towards the headlight.


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You want to go under the rad support and into the fender. Here's where you want to take the fender liner out/down on the right side of the wheel well. Refer to http://9thcivic.com/forum/threads/resonator-delete-si-sedan.4811/ for pics of the wheel well liner (THANKS@smokedditty) YOU WILL BE REMOVING THE 3 PIECES HE HAS MARKED WITH AN X

Once you get the liner out of the way, lightly wire tie the new fog light wire to the hood latch so it doesn't dangle. Right under the gromet for the hood latch is an empty gromet the you will drill a small hole through to get your wire into the car

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This is the other side of the gromet, again, right below thr hood latch cable.

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Now your going to want to get the switch and relay.

First, remove the under dash panel
http://www.collegehillshonda.com/instructions/civic/2012/4dr/ambientlightsi.pdf page 3

T-tap the main ignotion wire. It is the orange wire at the top of the interior fuse box

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Wire up the switch depending on what type of switch you have. My switch looks like this:

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And the wiring (leave a little slack on the wire for reinstalling the panel):

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This is the wiring diagram for the relay

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Once its all wired up, connect your new fuse and test these bad boys


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Not sure how to do this on models without factory fogs but i would imagine it to be the same.
Any more questions, ask them here or send me a PM. happy to finally give something back to the community!

webby i hope this is up to par for the DIY. Enter me into the next contest please!!
What is the wiring for this I have spent the last 3 hours I've wired fogs before but never done it this way what wire goes were exactly? Because the relay drawing doesn't help at all and neither does the pictures? Thanks for the help
 
I would like to attempt this on my 2013 Civic Si. I have read this thread and it seems like what we need to do is run a hot wire to the switch in the dash (which opens/closes the circuit). Then run that wire to the fuse box in the engine bay which is the male spade which powers the fogs. Do I have this right? If that is the case can I just tap the ignition (orange) switch and run that directly to the male spade which would mean my fogs are on any time the ignition switch is turned on?

Thanks in advance for your help!
 
I would like to attempt this on my 2013 Civic Si. I have read this thread and it seems like what we need to do is run a hot wire to the switch in the dash (which opens/closes the circuit). Then run that wire to the fuse box in the engine bay which is the male spade which powers the fogs. Do I have this right? If that is the case can I just tap the ignition (orange) switch and run that directly to the male spade which would mean my fogs are on any time the ignition switch is turned on?

Thanks in advance for your help!

did you see this?
Well, a relay works like this in general:

Most commonly I have seen they are 4-pin relays.

So logically, in our case we have the following for the relay:
  1. Ground
  2. Positive 12V output to Foglights - this is what the relay controls
  3. Positive 12V input from Power Source that will power foglights
  4. Positive input from the Switch - that will trigger the relay and complete the circuit inside of it sending power from #3 to #2 (numbers are for this example only)
So, the #4 is coming from the foglight switch on the steering column. It seems that on the other side of the foglight switch, the headlight switch controls whether or not there is even 12V going to the foglight switch to be sent to the foglight relay.
My guess is that you could easily get under the steering column, and then splice the positive wire that feeds the foglight switch into the 12V that feeds the low beam switch (or any constant 12V for that matter, but this is the safest/easiest method), which would bypass the foglight switch's dependence on the low beam switch.
 
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