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The relay is a standard 4 or 5 connector automotive relay (the 4 connector version does not have the 87A on when relay coil off circuit otherwise identical and either will work for your purpose). They use standard 1/4" connectors or you can get a socket for them. Any auto parts store should have at least the relays if not the sockets. For the high current wires (from battery to relay, relay to fog lights, and fog lights to ground make sure the wires are of an appropriate gauge 18 or 16 gauge should suffice, as you don't want wires melting on you. For the low current wires (switch to relay coil and relay coil to ground) 18 gauge wire will be more that sufficient.

http://www.offroaders.com/tech/12-volt-wire-gauge-amps.htm They have a handy chart of what wire gauge to use in automotive applications.
 

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Discussion Starter · #42 ·
The relay is a standard 4 or 5 connector automotive relay (the 4 connector version does not have the 87A on when relay coil off circuit otherwise identical and either will work for your purpose). They use standard 1/4" connectors or you can get a socket for them. Any auto parts store should have at least the relays if not the sockets. For the high current wires (from battery to relay, relay to fog lights, and fog lights to ground make sure the wires are of an appropriate gauge 18 or 16 gauge should suffice, as you don't want wires melting on you. For the low current wires (switch to relay coil and relay coil to ground) 18 gauge wire will be more that sufficient.

http://www.offroaders.com/tech/12-volt-wire-gauge-amps.htm They have a handy chart of what wire gauge to use in automotive applications.
One final question, i think, and i should be good. When you say to take positive from battery, do you mean literally at the connection or is there a more appropriate location to connect for positive voltage in the engine bay?
 

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Just go straight to the battery, it is right there so don't have to run a lot wires and will allow you to keep most of the wiring in the engine bay. That is one reason that I suggested to put a fuse on the wire that comes from the battery.

Also did you check to see what all wires you had going to your head light switch yet (you can easily disconnect the headlight switch by removing the CD holder/interior fuse box access cover) and if pin 7 had constant power and pin 10 went to ground?
 

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Discussion Starter · #44 ·
plan on checking during my lunch (1.5hrs from now). I'll get back to you with an answer.

Thanks pcordes.
 

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Discussion Starter · #45 ·
Looking to get the remaining parts to make my harness. How do these look for specs?

Relay:
https://www.superbrightleds.com/mor.../12vdc-3040a-5-pin-universal-relay/1667/3844/
https://www.superbrightleds.com/moreinfo/work-light-accessories/5-pin-relay-socket-/1668/3843/

H11 Connectors:
http://www.newegg.com/Product/Produ...-_-pla-_-Automotive+Lighting-_-9SIA0WW0ZG1188

I'm worried about the specs of the relay. I don't know if the rating is right and if it should be SPST or SPDT. The inline fuse is easy enough and can get anywhere. Otherwise, I plan on just grabbing the wires and umbilical. I plan on just connecting the fogs up to the switch that freefocus got me. But from what I see, the fogs will only EVER be on when at least the parking lights are on. I have a problem with this. I really want the fogs to be on all the time without requiring me to purposely trigger them on OR without other lights being on.

pcordes, if I want these to come on with the car being turned on, not requiring a switch but the key in the "on" position, what would you suggest I do to achieve this? That's ideal for me.
 

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SPST should be fine for what you want, just turning them on is the only function desired.

Getting trigger power from the parking lights is the normal way to wire fogs, keeps you "legal" as running lights are supposed to be on when fogs are in use. Allows use without headlights & with running lights for those really foggy/snowy times fogs are actually useful. You can leave the switch always on, so they come on automatically when headlight switch is turned to park.

Getting trigger power from anything powered up with the key on would work to make sure they aren't left on accidentally, gives you freedom to use them any time the car is turned on but it isn't "road legal" so you have to remember to turn on the parking lights when using them. Not as convenient in most cases.

It's kinda like using the high beam circuit for trigger power to switch & relay for driving lights. Then they can be switched on to light with the high beams, and the dimmer cuts them off with the high beams. This saves hitting two switches to dim both high beam systems, and is a requirement for Rally vehicles for that reason.
 

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Discussion Starter · #47 ·
SPST should be fine for what you want, just turning them on is the only function desired.

Getting trigger power from the parking lights is the normal way to wire fogs, keeps you "legal" as running lights are supposed to be on when fogs are in use. Allows use without headlights & with running lights for those really foggy/snowy times fogs are actually useful. You can leave the switch always on, so they come on automatically when headlight switch is turned to park.

Getting trigger power from anything powered up with the key on would work to make sure they aren't left on accidentally, gives you freedom to use them any time the car is turned on but it isn't "road legal" so you have to remember to turn on the parking lights when using them. Not as convenient in most cases.

It's kinda like using the high beam circuit for trigger power to switch & relay for driving lights. Then they can be switched on to light with the high beams, and the dimmer cuts them off with the high beams. This saves hitting two switches to dim both high beam systems, and is a requirement for Rally vehicles for that reason.
Thanks sailor.

I was unaware that having the fog's operate independently from the parking was not street legal. How come it is required to have DRL's on while fogs are also on? So since I have the stock fog/headlamp switch, I would be required to turn the switch to the parking lamps and pull the knob out just to use the fogs. Not a big deal.

As for wiring, I'll probably wire it as pcordes has instructed earlier with the wiring diagrams and his drawn wiring schematic. If that relay, relay socket and H11 connectors look legit, I'll probably purchase them within the upcoming day(s) and start wiring a harness together.
 

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DRL's are a bit of a separate subject, "required" only as equipped on newer cars AFAIK.

Running lights on when headlights are in use is an older one, simply to make the car more visible to others when headlights are needed. The fogs are an alternative to the regular headlights, and you can usually use them alone with the parking lights (actually marker lights in this case) when conditions warrant their use. When it's NOT foggy/snowy enough to need fogs by themselves, headlights would be required when dark or otherwise directed (like PA construction zones).

Honda for one, avoided any question by wiring optional fog lights to only come on with the headlights - making them relatively useless IMHO.
 

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As stated by sailor either a SPST or SPDT relay would work, SPST = Single Pole Single Throw (1 switched contact (87)), SPDT = Single Pole Double Through (2 switched contacts one (87A) is on when the relay is off, and the other (87) is on when the relay is energized), you would just use pin 30 on the relay for the power source from the battery and pin 87 to the fog lights (85 and 86 are the switched power and ground for the relay coil).

If you did indeed want the fogs to be on whenever the car was on, all you would have to do is have the relay feed off of a power source that is on when the car is on, instead of having it switched like previously illustrated, basically having the ignition switch being the switch. Perhaps such source could be the radio on signal, pin 2 (should be a Yellow/Green wire) on a 05-07 radio, or since the relay would be under the hood, there is probably a hot in run power source in the underhood fusebox area.
 

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I was going to suggest the outer fuse box as well... No need for a hole in the firewall to have a switch since it would always be on when the engine is running.

Why do you want them on all the time?
 

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Discussion Starter · #51 ·
I was going to suggest the outer fuse box as well... No need for a hole in the firewall to have a switch since it would always be on when the engine is running.

Why do you want them on all the time?
Sorry I just noticed that you and pcordes responded after sailor. Didn't get a notice.

Well, I wanted them to come on as my car's DRL's, since my car doesn't have them. But I didn't realize that the amber lights had to be on with the fogs to make them street legal. So that ruins that idea.

Is there a way to add the relay to my fuse box (engine bay) so I don't have to drill a screw to mount it? I want to try to make this as neat as possible.

I'm probably going to buy the items today/tomorrow that I need and begin a plan for proper routing of the lines from the fogs, to the relay through the firewall to the switch.
 

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Your car doesn't have DRL? I don't know if you would get pulled over for just fog lights on. Unless the cop was having a bad day.

I'm sure there is a way to do it like that. Of course if you didn't want to drill and have extra wire laying around. Would it be possible to run it under the windshield cowl and down through the cabin filter? And then across the interior? Just put a tube around the wore to keep it from the elements.

Came up with that just now.
 

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Discussion Starter · #53 ·
pcordes, I have an update:

I just got done doing some work in my car during my lunch and finally had time to look at the current wiring harness for my switch. It has all of the wires you mentioned that you mentioned on page four with the wiring diagrams and pin callouts. So the wiring adapter the freefocus got me is not required. (still, thank you freefocus!)

Why would my switch have the pinouts for fog lamps if I can't seem to find the wiring harness in the engine bay? Wouldn't you think that if they wired my switch connection for fogs, that they would have at least put the fog light wiring harness somewhere into the engine bay for fogs to be added later???? I would think that the fog light wires have to lead somewhere, don't you?
 

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Gudziel,
I think a previous post of mine, in this thread, has the instructions you need: http://www.focusfanatics.com/forum/showpost.php?p=6858521&postcount=37 specifically:
As you can see the power goes into the headlight-fog light switch at pin 7 which is labeled as red (but is actually Green/Red in my car). Make sure that you have power at pin 7 at all times except when the highbeams are on

So what you will want to do because it does not seem like your car has the rest of the fog light wiring and you will have to make your own, is wire from pin 3 to the coil of a relay (relay pin 85) and wire the other side of the relay coil to ground (relay pin 86), then from the battery run a wire to pin 30 on a relay then run pin 87 to one side of the fog light connectors and the other side to a ground point near each fog light, and pin 87a of the relay leave disconnected. For the wire that goes from relay pin 87 to the fog lights I would actually run 2 wires from it, one for each fog light (so may need to use a 1/4" connector for a larger wire so that both wires can fit into it). For extra protection, you can put an inline fuse holder between the battery and pin 30 on the relay.
As for where the wires end up in the car, your guess is as good as mine. I recently asked a similar question regarding the subwoofer wiring, which fell on deaf ears, as the 8 pin 4 wire subwoofer connector is behind the radio but when I looked in the cargo area for the subwoofer connector none was to be found. My personal guess is that the factory fog light wiring ends at the firewall bulkhead connector, has the pin on the interior side but not on the engine side. Another wiring mystery that I have is I have the wiring for heated side mirrors in the doors, the fuse for it, but no power to the fuse when the defroster is on and no continuity from the fuse to the mirror connector

So what I would do, assuming you have power at pin 7 and chassis ground continuity at pin 9 of the headlight connector, is I would splice in my own wire (remove the existing wire from the headlight connector and properly insulate it to avoid a possibility of a short circuit and then use the matching wire from the harness snub you got with the switch in its place) into pin 3 and run that to the relay as I described in my previous post on the wiring. If you don't have power at pin 7 and/or ground at pin 9 you would have to get those taken care of as well.
 

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Discussion Starter · #55 ·
Gotchya pcordes. Thanks man.

I can't believe you don't have continuity from the fuse to the mirror connector. That's an odd one. Hmm...

I'll look into buying the parts I need (hopefully) soon and start getting my wiring all situated. I want to get this all done sooner than later before the weather starts to get bad out.

Thanks again.
 

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The heated mirrors may only be available on the Focus ST models so those vehicles probably use a different car wiring harness(which probably also has ABS and traction control) so the wiring to the body side of the door connector just isn't there, even though the wiring in the door is there.
 

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Discussion Starter · #57 ·
Ok. Well I've just re-read this thread and would like to ask a question or two and finally get the fogs running.

Since I want them to come on automatically and not have to worry about switching them on, running a wire through the firewall, splicing the current switch, etc I feel it is best to hook them directly up to a power source inside the engine bay. To do this, would you guys feel this is acceptable?

I want them to come on when the key is turned to the on position, as well as turn off when the key is turned to the off position. When looking at the fuse panel (in the engine compartment) I'd like to place an "Add a Circuit" into there that would provide power to the relay. Now from pcordes' drawing in an earlier post, I see that +V is going from the battery to a 15A fuse to pin #30 on the relay. But he also has pin#3 from the switch harness going to pin #85 on the relay. Can I just forget about the switch harness (inside the dash) and wire the relay as such:

#30 & #85 - same lead from +V w/ 15A in-line fuse. This would come directly off of the "Add a Circuit" that I place into the fuse box.
#87 - Provides +V to fogs (other side of fogs to ground)
#86 - Directly to car ground

The only difference that I'm doing would be removing my need for the switch inside the car itself by wiring both pins #30 & #85 of the relay to the same power source in the fuse panel. I think using fuse #8 (ignition switch/starter solenoid) is the proper fuse location to pull power from, but it currently utilizes a 30A fuse.

Three questions:

A) MOST IMPORTANTLY: Will this work? [dunno]
B) Is fuse #8 the best fuse location to pull my source voltage from or would you more knowledgeable gurus have a better fuse in mind?
C) If so, is it ok to place an "Add a Circuit" into that fuse slot with a 15A fuse feeding the fogs and leaving the 30A feeding the ignition switch/start solenoid?

I really thank you all for your help.
 

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I would run pin 30 straight from the battery using an inline fuse holder, that way you have a good solid positive connection, and not potentially overloading wires in the fuse box with the higher current that the fog lights use.

As you want to use the fog lights as DRL like lights, then for pin 85 just need to find a switched power source to trip the relay when the car is in "RUN". As the relay coil uses fairly low current any source for this would do, perhaps off of either fuse 19 (heater blower motor) or fuse 29 (speed control servo & ABS) as both are hot in run and are for "non critical systems" i.e. not needed for the car to run or safety devices (PCM, air bags, brake/turn signals, etc). I would probably personally go off of fuse 29 as it probably only has the cruise module on it as ABS is a relatively rare option. I would definitely not use fuse 8 to control the relay (pin 85) as that is hot at all times so the fog lights would always be on.
 

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I agree with pcordes, do it off a fuse that isn't relied upon in case of a wreck or anything like that. Its not worth the risk of blowing a fuse and possibly crashing or damaging something.

As to adding a fuse to something that big, I'm not sure... I always read you want to put it on the lowest amp that you can, on the interior anyway.

This may be dumb so you can just ignore it but why couldn't you just attach positive and negative to the battery itself? Is that a very bad idea??

Google brought up some results for a Subaru and a Civic with initial results, couldn't really tell what they did.
 

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Discussion Starter · #60 ·
Thank you both for your responses.

I agree with both of you. I do not want to run off of anything where it would blow the fuse it is attached to. But I'm under the impression that if I were to even run the "Add a Circuit" off of an important source, and one of the fuses were to blow, it has no bearing on the other. Correct?

As for pcordes' idea about running off of cruise control, my car does not have that option, nor ABS. So I highly doubt I have the connections in that fuse location. I can check though.

Would it be unwise to take the fuse #19 (Heater Blower Motor) as it is rated for 40A and run a 15A fuse off of that? I do not know how safe it is to run an "Add a Circuit" off of a fuse location rated for more than double it's requirement. Now I understand that the lights will only pull so much and no more than what the in-line fuse will allow. But I just want to make sure that I am safe in going off of that location.

Please, comments?
 
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