wiring up a relay to fogs without a switch?

[giggitySI]

so i wired up my fogs to my running lights, and they worked fine for a little while, then the passenger side went out so i replaced the bulb and the fuse cause that blew too, and not even 2 months later, its out again and im thinking its trying to draw to much power to power the 2 fog lights and the 2 running amber lights and kno a relay would kinda help that, but all i can find on how to wire up a relay is with a switch which didnt work the last time i tried to use a switch, so any suggestions? jus want a relay in there wit the set up i have now, thanks

 

[leothelion]

What you need is an SPDT relay.
http://www.the12volt.com/relays/relays.asp -Cue angelic music
its pretty easy to set up, just ask if you have any questions.

here is how to wire it up:
85-pos from parking light fuse
86-neg-ground anywhere on the frame or ground wire
87-pos output going to fog lights
87a-This is a useless wire in your set up, just cap of the wire(or terminal) and leave it be
30-this is called the "common" power, this is a 12v pos input from the battery.

you can either solder directly to the contacts on the relay, or you can get a relay harness, which has multi colored wire leads coming off it, since you are capping off one lead, (87a) i would suggest getting a harness, so all you have to do is tap the end of that wire off.

here is a link to ebay where you can buy one, or go to radio shack and pick one up.http://cgi.ebay.com/12v-BOSCH-RELAY-plus-SOCKET-SPDT-harness-BULK-LOT-/110685471166?_trksid=p3284.m263&_trkparms=algo%3DSIC%26its%3DI%26itu%3DUCI%252BIA%252BUA%252BFICS%252BUFI%26otn%3D21%26pmod%3D110678368597%26ps%3D54#ht_1396wt_1141

 

[giggitySI]

holy hell thats kind of confusing haha im not good with wiring or anything so it might take ma while to understand that haha but thanks man, so this will work? i wont have any issues wit this again?

 

[leothelion]

this will work in the following system.
-you put a wire into the fuse box under the dash for your parking lights. lets call this wire (A).
Wire (A) gets connected to Contact (or wire) (85) on the relay, this is the switching wire. Inside the relay is a coil of wire, when the power from the parking light fuse hits that coil, it makes a switch inside go from one contact to another. in other words, i turns the power to one thing off, and turns the power to another thing on.
(86) is just a ground, which you need for a complet circuit back to the car battery.
(87) is the wire that gets powered up when the switch is engaged from your parking lights, however, instead of drawing power from the weak parking light fuse, this is drawing power directly from the car battery.
(87a) is where the power from the car battery normally flows, but since you dont need this power for anything, your just going to cap off (or basicaly cover up any exposed metal that would allow current to flow) the wire.
(30) is just a positive comming from the battery that gets redirected by the switch inside the relay.

cool?

 

[giggitySI]

yea ill try it, i got a sweet deal on another fog light kit that comes wit everything instead of cheap ass wiring harness, and a full HID kit for 230 bucks off password jdm so i might do that if i cant figure it out. thanks man i really appreciate it

 

[leothelion]

yeah that would work fine. a complete kit will come with a "dead end" relay, as opposed to a spdt, only difference is that instead of turning off the power to one line and switching it to another line, it only turn the power on and off to one line, so its better for the application that your doing. good luck man.