12 Volt signal wire
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12 Volt signal wire
Can anyone tell me what color is the 12 Volt signal wire comming off the OEM fog light switch? The wire that allows the fog lights to kick on when you switch your headlights on.
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They are Honda OEM from the dealership. Previous owner got them like that. I am looking at my Chilton manual and I cant seem to match the wires to the diagram.
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From: Charlotte
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looking at a schematic for a 2004, it looks like you need to tie the blue wire on the switch to a power source. i would put it on the red/yel of the parking lights. that way you won't forget to turn them off and kill your battery (like i have on previous cars.) you'll have the warning buzzer to remind you.
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From: NV
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yeah i used the park lights for mine too. and that way you can leave the fog button pushed all the time and they will turn on automatically with the park lights.
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Its so funny u say that because I know its the blue wire for the 2003 and lower. But I don't have a blue wire coming off the fog light switch. I am looking at the Chilton book and it shows 5 wires coming off the switch. In reality I have like 9, and the Chiltons shows a blue wire.. I dont have a blue wire coming off my switch. I am pretty sure these are OEM lights. I have OEM glass housings, an OEM switch and everything its even in the OEM loom. If it helps I can take a picture of it.
If I wire it to the 12 Volt Acc wont it go off once the ignition is off?
If I wire it to the 12 Volt Acc wont it go off once the ignition is off?
Last edited by 04 Honda Civic; Oct 31, 2009 at 03:37 PM.
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From: Charlotte
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if you don't have blue, you prob don't have Honda OEM, but an ebay set. the ebay's are almost identical, that's why so many have them. if you have a multimeter, you can ohm through the switch while actuating it, and figure out which wire goes to the fog light relay.
Last edited by electric130; Oct 31, 2009 at 03:43 PM.
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Do I have to have the switch plugged in while I check it? I always thought mine was OEM. The bulb housings are glass and OEM Stamped Stanly on them. Unless the man who owned the car before me got them installed afterward.
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Ok I checked the wires with out the switch plugged in, but I doubt it matters. Here is what I have.
Starting from the top left of the switch to the bottom right.
A single Red and Yellow Wire (Didn't get power with the lights on)
Next one to the right of that 2 red and black wires connected to the same pin. They each got 12 Volts with the headlights lights on, and no Volts with the headlights off.
Next one to the right of that is Red and black only a single wire
Next one to the right of that pin is 2 solid red wires.
Below the spot of the red and yellow wire is empty.
Then under the spot of the 2 solid red wires there are 2 red and white wires.
Any ideas. I am assuming it has something to do with one or both of the red and black wires?
Starting from the top left of the switch to the bottom right.
A single Red and Yellow Wire (Didn't get power with the lights on)
Next one to the right of that 2 red and black wires connected to the same pin. They each got 12 Volts with the headlights lights on, and no Volts with the headlights off.
Next one to the right of that is Red and black only a single wire
Next one to the right of that pin is 2 solid red wires.
Below the spot of the red and yellow wire is empty.
Then under the spot of the 2 solid red wires there are 2 red and white wires.
Any ideas. I am assuming it has something to do with one or both of the red and black wires?
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From: Charlotte
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very possible. no, you'll want to remove the switch and check on the backside at the terminals. what you're trying to do is trigger power to fog light relay 1 on the red/yel wire as you desire.
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From: Charlotte
Rep Power: 291 Re: 12 Volt signal wire
i think we posted at the same time. try getting a jumper wire and put 12+ on the red/yel with the switch off. if the fogs come on, take the switch out and manually actuate the switch while reading resistance. check the other terminals to see which wire is connected to the red/yel through the switch. when you find it, that's the one you want to tie to the park lights or acc.
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odd..I jumped the red/yel wire and my Driver side light came on. Both my high beams and my other passenger side light came on and it looks like I have DRL lol..Did I **** up?
Could it be that each red black wire in that pin is for each fog light?
Could it be that each red black wire in that pin is for each fog light?
Last edited by 04 Honda Civic; Oct 31, 2009 at 05:28 PM.
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The fog light switch is only powering the relay coil which is doing the switching of the fogs.
I have attached the wiring info from the manual, these should be factory colors.
Maybe it will help clarify.
I have attached the wiring info from the manual, these should be factory colors.
Maybe it will help clarify.
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From: NV
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as far as i know, oem lenses are polycarb. also a dead giveaway is the glare shield around the bulb (metal cylinder around the sides of the bulb) that only oem fogs have.
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From: Charlotte
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From: NV
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also if anyone is thinking of doing this for a coupe, its a bit different. using blue wire is not correct, that will keep the fogs on all the time like a DRL even if switch is off.
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Ok here is what I have:
Red/Yellow: To red white I have 2 ohms lights off, 0 ohms with park lights on, no continuity with headlights on.
Red/Black: I have cont to red yellow and solid red 2 ohms as well but no cont with headlights on, also have cont to red white with no resistance
Red/Blue: has no continuity to anything
Solid Red: red white 4 ohms with lights off, 0 ohms with park lights and headlights no ohms but continuity.
Red/Yellow: To red white I have 2 ohms lights off, 0 ohms with park lights on, no continuity with headlights on.
Red/Black: I have cont to red yellow and solid red 2 ohms as well but no cont with headlights on, also have cont to red white with no resistance
Red/Blue: has no continuity to anything
Solid Red: red white 4 ohms with lights off, 0 ohms with park lights and headlights no ohms but continuity.
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From: Charlotte
Rep Power: 291 Re: 12 Volt signal wire
you can't do that. to take resistance readings, at least one side of the circuit must be isolated, as well as you can damage your multimeter by taking resistance readings with the power on. that's why i said to disconnect the switch and take readings at the terminals of the switch.
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From: Charlotte
Rep Power: 291 Re: 12 Volt signal wire
that still doesn't make sense. if the fog light switch was unplugged, sitting in your hand, and you're reading at the terminals inside the back of the switch, operating the headlight switch would not change any readings. you should have terminal markings such as numbers or letters. there should be no wires or colors at all.
Ill post back with them in a few minutes. 
