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Help with dash Wiring Harness schematic

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Old 07-21-2017, 09:25 AM
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Default Help with dash Wiring Harness schematic

I am wiring three sets of lights (roof spots, bumper floods, bottom of bumper fogs). I would like to use three of the switches on the left of the dash/steering wheel (US). One is already wired for the bottom of bumper fog lights (although I cannot get power to them and am rewiring). The other two are harnesses were connected to non-functional fake switches (apparently I didn't get those options). Is anyone aware of a schematic that says what each wire on each harness does?




Second from top wiring harness on left of dash (US). Had a blank/non-functional cover



Top left-of-dash wiring harness (US) . Goes to foglights.



Fourth from top wiring harness on left of dash (US). Had a blank/non-functional cover
 
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Old 07-21-2017, 10:10 AM
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I don't know the switch purposes off the top of my head, but to use those circuits you will need to turn on those options in the BECM.
 
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Old 07-21-2017, 10:15 AM
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Hmm. Hadn't thunk of that. All I reallly want/need is a hot feed off the ignition. I suppose I can wire that, myself.
 
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Old 07-21-2017, 10:45 AM
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Just tested all the connections on the three harnesses. They are all wired a bit differently. The top two have a hot wire from the ignition on #2. The fourth (bottom) harness is wired directly to the battery on #1, and to the ignition on #4. Looks like I've got some creative wiring to do.
 
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Old 07-21-2017, 11:29 AM
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Easier to get three cruise control switches and pigtails, which are latching switches. They run your own wiring harness and relays.
 
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Old 07-21-2017, 01:10 PM
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That's just about my plan ... except rather than Cruise Control switches, I've found two more Front Fog Light switches (and pigtails) on eBay. I'll use the format of the already installed light switch and try to replicate it in the two new switches. I'm seeing some trial-and-error in my future to get it right, but that's half the fun.
 
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Old 07-21-2017, 01:24 PM
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Fog switches are momentary I believe, whereas cruise control switches act like normal switches. I'd avoid using the wiring for the fog switches if possible, as its complicated and goes through the BCM, and you can only power them on when the headlights are on and car in Acc2 position.
 
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Old 07-21-2017, 02:14 PM
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Jeff is right. The fog light switches are momentary contact. Cruise control switches are latching. You can put front fog light switch covers on them if you want to make them look like a light switch but the latching mechanism is what you want and need. The covers are interchangeable.
 
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Old 07-21-2017, 02:37 PM
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What I did is buy 5 cruise control switches, and wired them all up together in one go (daisy chain the 12v, ground, and dash light wires, with a bundle of individual swifcb leads coming out) so you don't have to do it again and are ready for whatever accessories you add later. Small enamel paint brush and white paint to label the covers. Next up I'm putting a relay panel to sit on top the fuse box in the engine bay.
 
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Old 07-21-2017, 04:37 PM
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I'll break this out into what I do understand, and what I don't.

I understand the daisy-chain concept and had wondered if it would cause a problem linking several switches together with one that already does what you want it to. "Problem" as in draw too much and blow fuses. I also understand that the easiest way to wire D2 auxiliary lights is to get a switch that locks-down and stays on until you press it again (as in a cruise control switch).

What I don't understand is why two more fog light switches, exactly like the one I'm keeping, that turn on when you press them and stay on until you press them again, won't work if daisy-chain wired into the existing "factory" fog light harness with only the outbound load to the different relays/light assemblies changing. Do they have some funky form of relay?

And ... pardon my ignorace ... but I don't know what swifcb means (and apparently neither does Google).
 


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