Looking to hook up an amp and sub under rear seat in my 04 FX4 SCAB. I have a LOC but am not sure where/how to hook it up. I would rather not pull out the stock head unit, if at all possible. If thats the best route, would anyone have recommendations on how to get the HU out and how to hook it up? Is it possible to hook it up at the rear door speakers? If so, how? What about the remote wire? Where should I run it, hook it up too. Any help would be greatly appreciated. Lastly, thanks to everyone who answers questions on this site. Your opinion and advice are greatly appreciated. With 3 kids, any money I can save on self-installation is great! Thanks again.

 

It would be best just to tap the rear speaker wires. Behind the head unit is by far the easiest place to add a convertor since the HU will slide out anyway if you use the radio removal tools. Anyway, I suggest getting a few of the scotch lock wire taps they work well for this type add on and still preserve factory wiring. Can't remember the wire colors but you can find them if you search for them online. As for remote turn on lead just use a switched 12v source if you don't have the LOC with the remote turn on built into it.

 

Tapping off the rear of the head unit is by far the easiest. If your '04 is like my '05 (I'm almost sure it is) you won't be able to tap off the speakers in the door since there's a huge connector that connects everything electrical in the door to a bigger harness inside the truck. There are no spare pins to route additional signals. So unless you poke new holes in the door frame to route your tap, it can't be done easily.

THe next best is to use the audiophile sub connector that is a connecter that starts behind your HU and runs to the bottom of the driver-side passenger seat.
In my screw, the connector is buried along a ledge under the carpet and comes out from a bigger harness that runs under the plastic diamond cover piece where the carpet meets the door. I think you might have the same. That connector has live 12V power on a pair of 16awg wires, a sub enable line and a shielded coax signal line. You should be able to drive that with your LOC from the HU.

 

Thank you for the advice. Appreciate it.

 

dragonman,

Is the audiophile cable present even in vehicles without the audiophile system? I know that in 2003 and earlier models you did not have the amp wires present if your truck didn't come with the premium system. I always said that it costs automakers more to produce different wiring harnesses for the different options rather than just producing a single harness that will handle all options. Looks like they may have finally caught on.

 

So your saying I can hook up the LOC under the plastic diamond cover piece rather than behind the HU? If thats the case, thats great. Any idea where I can find a wiring diagram for the 04? Ive searched the net and cant find the 04 or 05, as I assume they are the same. Thanks.

 

cgorris--
I have a non-audiophile setup. I have the sub harness present in my truck. The unused 3rd connector for the HU sub out is taped back along the main harness that it resides. The sub end of it was just hanging there and taped against the floor buried under the carpet under the driver rear passenger seat. Kinda tough to get at it, but you can yank it out starting from where it branches off the main harness that runs along the side and up the side of the back wall. There's a little slit cut in my carpet I guess for where it would otherwise come out for the audiophile sub

mcclenj--
No, there's no room under the plastic cover. You can pull it up and see the harness there, and that's it! Best to put behind the HU since there's enough room in there to put in a couple of 6-packs!

Found this in another forum not too long ago from a member named caimakale. It's a rar of a pdf scan of the '05 schematics... it's probably very similar if not identical to the '04

Last time I posted the link of the original post, it was edited out! So here are the files' links only. hope they're still there.
http://home.comcast.net/~myfordf150/...-150.part1.rar
http://home.comcast.net/~myfordf150....-150.part2.rar

 

That is good to know. Thanks for that info. Even an old salt learns something new once in a while.

 

I wasn't able to download the wiring diagrams but I am in deperate need of them. I tried to install my single 10" sub and amp to my stock head unit tonight but I couldn't figure out what wires to tap the LOC into. I pulled the speakers out of the doors to figure out which wires but the wires on the speakers dont match anything going into the back of the HU. Someone please help. I need to know what wires on the back of an 04 6 disc changer are for the rear speakers. Or if someone can email me the diagrams that also would be greatly appreciated. mcvey301@buckeye-express.com

Thanks in advance for your expertise and assistance.

 

Got this from the12volt

 

Thanks alot for the help. This board is priceless for all of the information you can find. Maybe that is why my wife thinks I have a little bit of an addiction to it.

Anyway, does anyone know where I should hook the ground wires to on the LOC?

Hopefully I can hook this stuff up tomorrow morning.

Thanks again.



JUST GOT IT ALL HOOKED UP AND IT SOUNDS GREAT! EXACTLY WHAT I WANTED. THANKS AGAIN.