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Right Being new to this, I may have rushed through the process of wiring in my new head unit and by the looks of things I made the amateur mistake of not wiring the constant so my headunit isn't remembering any settings, Ive throw out all my drawings after putting it together anyone know the colour or striping of this wire? or have I infact gone horribly wrong and missed a different wire?

Cheers guys

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  • 1 month later...

Ha i got the views but no answer? Am I wording it right or do people not know if that wire exists, my headunit just wont keep settings and ive got a big enough battery so its not losing power and then losing the settings, so im sure its a wire i just havent got

Hey dude.

Damn i really want to help but i can't remember the exact color of the hard active..

I apologise if i'm telling you something you already know; but here's how to investigate and solve your issue.

It seems what you've done is plugged the switched active into the head unit instead of putting the hard active in; as you said yeah.

What you can do mate; is grab a multimeter.

Get all the wires coming out of the car in your hand and strip the ends.

Put one end of your multimeter on any metallic bolt or surface you can find and the other on the ends of your cable.

The hard active obviously is the one that will get voltage; even when your key is not in the ignition; so... that would be it!

hmmm... i'm trying to remember with the 34... i'm thinking black wire with white stripe. but try em all.

Just to clarify; you can tape up and disconnect the switched active you have got in your headunit now.

I think the audio techies call it the "remote" wire. Its supposed to be for an amplifier or other equipment. It's Switched so that when you turn the car off; the amp doesn't sit there and suck the battery away.

Hmmm cause I have the remote Wire set straight to my amps with first wire from head unit to first amp then from first amp to second amp ( so you get the gist of it) but it still doesnt seem to work. I may be making it more difficult but essentially the only wires from the head unit that I didnt wire was essentially an orange and a brown (telephone muting and illumintaion i believe) my old head unit kept everything fine though so i doubt im missing something in my car. Asked the manufacturer pretty much the same question but more specific and all they did was send me a wiring diagram and tell me to get it installed professionally (possibly wise words but I would like to do it myself)

But you reckon black with white stripe from car end?

Can't believe nobody else has replied...

I just realised I'm retarded.

The head unit needs both of the power wires to work properly. It needs the constant active and it needs the switched active that is turned off when you pull out they key.

In honesty there is no way I can identify the wires from their colors because in different models they're likely all different >_<

Lets just ignore the rest of the wires and focus on finding the relevant ones.

I think what has happened is; you have got the switched active in the correct place; so we can leave that alone; because your sound system fires up when you turn the key; and turns off when you pull the key out right? It just forgets all your settings.

And if the cables left over are illumination & phone mute then the only explanation is that you have already Joined the constant active to your head unit; but to the wrong place.

Like you've asked all you need to do is find the constant active on the car side and join it to the right cable coming out of the head.

If you've soldered the joins you should be able to just stick your multimeter on the solder and find which one has 12 volts with no key in ignition.

If you haven't soldered you'll have to strip your connections to get some copper to test with. sorry dude.

Anyway when you've found that 12volts with the key out (it will be the only one); just join it to a different cable; hopefully your new diagram shows which one it is?

Yer havent soldered yet, But im thinking that whilst doing that its probably a solid idea (no pun intended)

Thanks for your help though man I'll test it out in the weekend and try find the right one then solder them all up.

Quick question with soldering though. Do i still need to re cover the solder with electrical tape? just wondering if the solder touched solder is it going to transfer signals and short?

I myself have also realised im slightly more retarded when whilst looking for this "constant" I had always been looking for "constant" or "switched active" instead of looking for the wire that relates to the battery. But still props to you for helping me realise I need to learn to read instead of jumping into things and also helping me solve my issue. just need to test for the cars wire now because I do believe I Know the wire from the headunit.

If I was to test the end of just the car wires, with nothing attached and the key out will it still read the same as though it was attached to a headunit wire? If im making sense? :P not much of an electrician but I enjoy learning =]

Haha; Yeah man.

I think i see what you're asking.

If you tested the car side constant for voltage while it were disconnected from the head unit and stripped in your hand; it would read 12 volt.

If you tested it whilst it was soldered and joined to the head unit by placing your multimeter on the solder join it would still read 12 volt.

Think of it like measuring water pressure in a pipe. There's 12 volts of pressure in that cable and until it touches something that opens the flow the pressure will stay there stored up.

You've confused me with what you said up top... the constant and switched do both relate to the battery...

Edit Ooops: Yeah you definately need to tape up your solder joins. For the exact reason you stated.

Edited by Little
  • 1 month later...

Sorry long time no reply, Essentially, its there and I found it and I had wired correctly even, the one thing that went wrong is the wire stretched inside the plastic and diconnected, I reconnnected it with solder to keep it all together, works like a dream now.

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