Headunit Wiring Question

[VinnieZ]

Hey guys, I purchased a new aftermarket headunit and installed it using a harness. However, when I disconnected the factory radio, there were 2 wires plugged into it (not including the antenna). 1 of them went into the harness. The other I had no idea where it went. If you look at the picture below, it would plug into the more square outlet on the left. I dont have it plugged into anything right now and everything works. I am just curious as to what this is for? Anyone have any idea?

 

[VinnieZ]

anyone?

 

[silver4x4]

Either Amp for stock subwoofer if installed, 6 disc cd changer, or steering wheel controls are my best guess?

 

[VinnieZ]

Silver, Thanks for your reply.

However, I dont have an amp installed for the factory subwoofer (if thats what you are implying)...if thats not what you are implying, then does this mean that my factory subwoofer wont work?

I dont have a 6 CD Changer or Steering Wheel Controls...

Any other guesses?

 

[VinnieZ]

anyone?

 

[TheJackal]

Are you talking about that plug that has only one wire in it?

I have no idea what that's for, but it doesn't appear to do anything. I think I tried it once with and without it connected, and I couldn't find it doing anything different.

 

[Flounder]

Do you have rear controls?

 

[VinnieZ]

Jackal,
I believe it has 2 wires going into it, but I am not 100% sure.

And I dont think I have rear controls (at least audio controls). I have the rear vent in the console and I think thats all I know of.

So maybe it does do nothing?

 

[JohnnyBoy1102]

Mine has 2 plugs too. the second is probably for rear controls. if yours has rear AC controls it most likely has rear radio controls like mine does. its not making any difference having it unplugged in mine tho. i have aftermarket kenwood HU. does your car even have a factory amp in it?

 

[VinnieZ]

Johnnyboy,
I dont really have rear AC Controls. I just have 2 vents on the center console with a button to change from vents to floor and a power port (like ash tray port)....I have an aftermarket Pioneer HU...and how do I know if I have a factory amp? (sorry Im very new to this stuff)

 

[JohnnyBoy1102]

Well being that you have a factory sub then you most likely have a factory amp because you cant run a sub without an amp ( i think) cuz head units only put out like 50 Watts at the most which on a sub wouldnt do ****. I am not sure where it would be located, what year is your explorer? you could probably search it on wikianswers on something of that nature. any how i would think that the wiring for the factory amp is included in the one harness but dont quote me on that. lol this is why i prefer to just add onto my system rather than mess with factory stuff lol.

 

[JohnnyBoy1102]

This may help you out just a little. its for a 98 but they are probably similar.

http://www.explorerforum.com/forums/showthread.php?t=154055

 

[VinnieZ]

Johnny I think that helps a lot. I have a 2002 ford explorer. According to that post, they are for the factory amp I am guessing? So I need to get the red white AV cables and cut them and strip them...and do this:

Cut the 8 pin 4 wire connector off. You are left with a Red/black, Lt Blue/Red, Brown/Orange, and bare.

New HU amp wire (blue/white) connects to Red/Black
Positive RCA/speaker wire connects to Lt Blue/Red
Negative RCA/Speaker wire connects to Brown Orange
Bare is unused


Does this mean that my factory sub is currently not working at all if thats what those wires were for?

 

[VinnieZ]

also, i never thought to ask this but I got my harness from crutchfield and here is the picture:

What is the small one for? I didnt use that in my original installation

 

[JohnnyBoy1102]

Well judging by the pic that small white one is the RCA for an amp and possibly the remote wire judging by the fact that its light blue and white. i would think you would be able to just cut and match up all the wires from the crutchfield harness to the stock harness. you have a blue and white wire thats your remote amp turn on wire in most cars especially fords. my 98 explorer and my buddies 04 stang are the same so ur 02 explorer is too i would think.
basically with head units you are just matching all the colored wires up from the stock harness to the after market. the crutchfield harness should be tagged with right front speaker power and ground etc... and then just match them up like so.

Stereo Wiring Constant 12V+ Light Green
Switched 12V+ Yellow/Black
Ground Black
Illumination Light Blue/Red <---- these may be wrong, but the speakers i am almost definitely sure are right.
Dimmer n/a
Antenna Trigger orange/Blue

Left Front (+) Orange/Light Green
Left Front (-) Light Blue/White
Right Front (+) Dark Green/Orange
Right Front (-) White/Light Green
Left Rear (+) Gray/Light Blue
Left Rear (-) Tan/Yellow
Right Rear (+) Orange/Red
Right Rear (-) Brown/Pink

 

[VinnieZ]

Johnnyboy, thank you so much for your help.

The wire on the right is what I have and did not install. I have all factory speakers (until Friday) and a new HU (No Amp)

I installed the big harness on the left and everything seems to be working. I didnt realize at first that I needed to use this wire on the right. So does the wire on the left power the (factory) subwoofer even though there is only 1 RCA wire on it?

And it has a blue wire with a white stripe...what does that go to? the black is obviously a ground....Im just confused...

 

[JohnnyBoy1102]

Yea im not exactly sure how the factory amps are set up but i think that harness on the right is for an aftermarket amp. idk if the factory amp has an RCA port it might just be hardwired. its hard to say because iv never been in a car with a factory sub and amp. if you wired it all up and everythings working then you should be fine. if you can locate your amp and see how its set up and what color wires are going where then you should probably do that.

 

[kelly2]

the white plug on the right is the amp turn on and signal wires for the factory sub (if equipped).

the harness you mentioned earlier with one or two wires isn't important. i know one of the wires is a VSS (vehicle speed sense) wire

 

[JohnnyBoy1102]

thats what i figured cuz my second stock harness is unplugged and my radio works fine the only thing that confuses me is the after market amp and sub part because i dont know anything about either. i am curious, does the factory sub have an RCA in? or does it just hardwire in?

 

[jordan87]

i have an 01 4dr, and i picked up a scosche harness for it. now my stock HU is AM/FM/CD/CASS but the truck does not have a sub. it DOES have rear controls though. 1 plug does match while the other-squareone- doesnt match the new harness. this appears to be the white plug from above....do i just leave that unplugged and wire in the matching plug like stated above? im not usually this bad with this stuff but not being able to find a clear anser on if i have the right aftermarket harness is throwing me for a loop