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I'd been looking around in hopes of upgrading Dana's Wrangler's sound system.  I lucked out and snagged a factory subwoofer / amp off Ebay for only $37.  I wasn't even going to bother with this write up until I searched on how to go about it installing it, and came up with zilch.  The only thing searching yielded was other helpless souls posting on message boards trying to figure it out as well.  The dealership was no help and said they don't sell the harness to hook up the sub; it is supposedly part of the entire vehicles wiring system.  Apparently even the wiring schematic that would at least point me in the right direction was more than elusive.

I began my quest for knowledge by looking at Chris's Jeep since his Sahara Ed came off the line with the console bumping.  I tore into it (it's amazing what friends will let you do if you just don't ask:) and tried to trace the wires and ended up more confused than before.  White goes to Black/Red which might go to Green somewhere and then to Blue changing again somewhere to Green/Red?  Do they make it that confusing on purpose or was there some kind of sale in the mismatched wire bin at R-Shack?

So I started from the basics.  There had to be a power and a ground, but there were 4 other unaccounted for wires.  Well, it has to get audio signal from somewhere, and the sub is a dual coil, accounting for 2 signals, which would be the 4 extra wires.  Now which one's which?  Remember when Red was hot and Black was ground?

The power was clearly coming from the fuse box since #3 is labeled "Sub."  But the thing that threw me was the fact that when we installed Chris's new radio, his sub didn't work until we hooked up a Blue wire in the stereo harness labeled "Power Antenna."  I still never fully figured that one out.  So I said screw it and began connecting wires my own way.

I determined with much deliberation that Green and White had to be the power wires.  I figured out with a blown fuse which one was hot.  To test all my wiring theories, I temporarily rigged it all up running power off the lighter and grounding off on a bolt.  I picked up a clue on the net that said the sub got signal off the rear speakers which made sense so I twisted together some temp wires off the radio to the sub and actually got some bass.  I celebrated then called it a night.

 

The next day, I went to Radio Shack and Circuit City to pick up a few things for the permanent install

  • Extra Wire

  • Connectors (I used the quick-disconnect kind so if the console or sub needed to be moved, it'd be an easy removal and then re-install)

  • Fuse Tap(s)- to easily utilize the actual fuse spot for the sub

  • 20amp Fuse(s)

  • Bass Blockers to keep from blowing the front speakers and to utilize them just for Highs and Mid Ranges (purchased at CC for $10)

 

Now that I had all the stuff I needed and thought I knew what I was doing, I dove in.  If some of the pictures of the radio wiring look odd, it's because at the same time I was installing the sub, I was installing a newer stereo at the same time.  But the wires that I spliced into were the originals from Dana's '02 so any TJ below that will be the same for this install.  At first I thought about making each wire a different color, but that wasn't cost effective, and besides Jeep didn't bother either.

I figured out what length would work to bridge between the back of the stereo and the sub, and cut 4 wires to fit as my speaker wires.  I snipped off the worthless sub harness and attached my new connectors to the ends. 

Since I wasn't making each speaker wire a separate color, I marked the corresponding ends with marked tape.

 Here are the wires you you want to go after:

L Rear (+) - BROWN/YELLOW to Sub BLUE R Rear (+) - BLUE/WHITE to Sub ORANGE
L Rear (-) - BROWN/BLUE to Sub VIOLET R Rear (-) - BLUE/PINK to Sub YELLOW

 

*The last picture here shows the Bass Blockers wired into the front speakers' leads (DARK GREEN & VIOLET).

 

 Now it's time to wire it for power.  I went ahead and played it safe by disconnecting the pos lead from the batt. 

To utilize the fuse box without the hassle of getting behind it, I used a Wire Tap from R-Shack (less than $2 for 6).  I had to trim the width of it a tiny bit with the Dremmel because of the smaller fuses that Jeep uses.  After that, you just slip the tap on the fuse and then push your wire connector onto the new terminal.  Then I tested it with a wire tester to see if I was in business.

 

 

 

Once I had the wire powered at the fuse box, I ran it back with the speaker wires and connected them all up to my Sub "harness." 

Next I ran the ground for the Sub to a bolt on the 4WD shifter assembly.

Sub Power - WHITE

Sub Ground - GREEN

 

 

It was test time again.  I popped the battery cable back on, connected the radio up, said a prayer, and turned the Jeep key back.  Shweet.  It all worked and the driver seat vibrated just enough.  I checked out the front speakers' output, and it was clear.  Now the fader can use also be used to decide how much high end is wanted.

The job was just about finished.  I got the wires up and out of the way and reinstalled all the gutted pieces while listening to some nice pounding rock.


 

I've seen a lot of bashing on the stock amp subwoofer set up, but I can't see (or hear) why.  First of all it's a Jeep, it's not a show car, and if you try to make it one, you will be awarded no points and may God have mercy on your soul.  There's no sense wasting space somewhere else to ensure that everyone else hears what kind of music you think "is da bomb."  And, also because it's a Jeep, it's going to be exposed to not only the elements, but unfortunately thieves.  So instead of tempting them, going with a stock $37 set up (new at $300) seemed like the white choice all the way around.