So I've finally purchased a Sosche FDMUS05 12" Sub and enclosure to place in my trunk. Now I've been trolling several forums in search of an ideal solution of how to connect the amp to the head unit. At first I was going to get a line-level converter and take the rear speaker inputs and get a set of RCA's out of them, but as I read several posts, I started to think that there was a better way.
Take a look at the wiring diagram below: https://www.allfordmustangs.com/forum...achmentid=5967
And take a look at these wiring harnesses from Crutchfield:
Going from the diagrams and the product descriptions, the smaller of the two wiring harnesses from Crutchfield definitely matches the J4 plug of the stock head unit. On that harness, there is a set of RCA cables coming out. It seems that these RCA's would plug into an after market head unit and the signals would be carried down the existing wiring to the factory Shaker 1000 amp/sub, which leads me to believe that there is a low-level output coming from the back of the Shaker head units.
My question to anyone that knows much about this stuff is, how would I take a RCA-to-twined cable and wire it into the J4 plug to make a proper RCA out to plug into the amp? I have a couple guesses but I'm not entirely sure.
So using 2 of these (I'll call them RCA-A and RCA-B):
I'm GUESSING that I would wire it like so...
RCA-A+ --> J4P1, Aux Aud 1+
RCA-A- --> J4P3, Aux Aud Shield
RCA-B+ --> J4P2, Aux Aud 1-
RCA-B- --> J4P3, Aux Aud Shield
Can anyone confirm that or let me know if that's completely wrong? I
In any event, I plan on positing my findings here since this seems to be a question that a ton of people have and the threads that address it die out before a solution is presented.
On a side note, I've also found some posts that suggest the remote power on and low level outputs on the shaker 500 output extend to the trunk somewhere, even though there is no sub/amp. When I start to tear things apart I will take a look at the J4 connector and see if anything is plugged into it, and if there is, try and follow it back to see where it goes.
I apologize for any confusion, somehow my links to Crutchfield and maybe Radio Shack seemed to break the post/thread.
Anyway, long story short, the wiring harness on crutchfield can be found if you do a search for "Ford Wire Harness"
The cables I was referring to on Radio Shack are part# 42-2371