# Mk4 Keyed Power Source.



## CousinVin (Apr 25, 2013)

What switched power did you mk4 guys use for your pressure switch? 

Also, to run power to the manifold and controller, I'm using an AVS switch box and a VU4 mani. Do I run constant through the pink that is labeled 12v or should that also be switched power?


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## CousinVin (Apr 25, 2013)

100 views and no responses?


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## macleanshaun (Sep 19, 2008)

We ran a 4 gauge power wire from the battery to a distribution block for the 2 compressors. And then used the headlight switch for the pressure switch power.


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## fasttt600 (Apr 12, 2007)

75x can be used as switched ignition for your application. It's under the drivers side dash. For the switchbox, I would use switched power as well because if someone breaks into your car they would be able to use the controls without the key if you used constant power. and that's no beuno


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## macleanshaun (Sep 19, 2008)

At least the switchbox has the lock on it as well. Personally I like to be able to air up or down without putting a key in.


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## CousinVin (Apr 25, 2013)

What is 75x? I'm trying to research it but can't find anything that actually says what it is and what it controls?

As for the pressure switch, wouldn't 30 work as well? the ignition?


Now I am going to make an addition to this as well. I am running an Analog system, so how would I go about wiring up the Vu4? does that just get constant power, or do I run it off of the same switched power source? It seems that the manifold MUST require more power than I could use at an existing fuse, right?


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## blue bags (Jul 1, 2009)

Under the dash on the left hand side, you will find a row or screw terminals with larger gauge wires on them. one of the left is labeled 75X. run a wire from there, to your trunk. This is your 'key on' wire. 

the pink wire from your switchbox goes to this. the 8 wires corresponding to the 4 corners(up and down) of the vehicle are wired to the VU4. you then ground the black wires of the manifold. 

the relay for your compressor is also going to run to the wire coming from the 75X. your pressure switch can either interrupt this, or the ground. I personally run the pressure switch on the ground side of the relay. 

hope that helps :beer:


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## CousinVin (Apr 25, 2013)

incredible helpful. The only question I have left is how the Vu4 gets power. Will that also be run to the 75x?


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## rgarjr (May 19, 2012)

VU4 manifold only needs ground.


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## CousinVin (Apr 25, 2013)

That doesn't make much sense. If it were wired through the switchbox, I would understand it. But this is how my wire look is set up. I have an extension, here :











With these wires coming off of that end. the blue and grey were something about being wired up to dump all if the alarm goes off, which I will not be wiring up.









These are the wires that come through to the bare end of the loom that was where the switchbox and vu4 harness get soldered together:










And this is all that was left after I soldered the corresponding corner wires together, coming from the Switchbox side:


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## blue bags (Jul 1, 2009)

it is wired to the switchbox, and the switchbox is powered. when you press LF^ it sends power through the trigger wire to the corresponding valve. the 8 wires you are hooking up power it.

dont overthink the harness. its there to make your life easier. do what the diagram says(if you have that harness im assuming you have a diagram with it) 

but what i explained above, is exactly what you need to do.


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## CousinVin (Apr 25, 2013)

Haha yeah. It makes sense now that I think of it. Now really all there is left to do is get working on it.


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