I was digging into the previous headunit install from the previous owner and I noticed that a few wires were spliced into on the factory side of the radio harness (behind the main connector) for dash controls (I think). Out of curiosity is it possible/manageable to replace the factory radio wiring harness with a new harness?

The dash controls don't work too well (volume control zooms to max sometimes) and I'm wondering if it's possible to start fresh or if I have to clean up what's been done already. Pics attached for the curious.

 

Apparently the installer used a generic adapter harness which lacked the wires that connect
with the s2000-specific dash (green/red) and mute (yellow/blue) wires, so instead of modifying
the adapter harness, they spliced the car harness. It's not clear from the picture whether they
cut them, but it looks like they may have just (hopefully) used a t-tap.
The problem with the dash control interface (DCI) could be a wiring issue, or it could be
lousy generic DCI.
I think it's going to be very difficult to replace the harness. If it was my car, and I'm
admittedly obsessive-compulsive, I'd remove the existing DCI, either splice back together
the wires if cut or remove the tap and insulate the cut well if the wire is ok, or splice
if not. Solder/heat shrink the splices, or use good quality heat-shrink butt splices.
Then I'd get a Modifry DCI and one of his adapter harnesses, either plug&play if compatible
with your headunit, or regular (which you'll have to splice to your headunit's harness).

 

OCD is A-OK with me.

I'm fine with soldering. My concern is not having enough wire to splice with on the connector side. Are the pins removable from the radio connector? Maybe I can salvage wire from another connector. The heatshrink butt splices also look pretty convenient.

Will the modifry DCI work with a kenwood X796? There's no 3.5mm remote input on the back of it. The remote wire in the manual isn't brown either (per modifry). It's light blue/yellow according to the page. Same thing?



And jesus your car setup reminds me of my home speaker setup.

 

In the actual instructions PDF on his site, he shows the Kenwood light blue/yellow for the dash and brown for the mute
as per your Kenwood manual, so it should work. Looks like he also sells a fully plug&play harness for Kenwood that will
save you a bunch of splicing for an extra $15 or so.
You can add/replace pins in the connectors - you can buy a reverse harness like this one for parts, though it was alleged
in a post long ago that the pins were the same as those found in an ATX computer power supply. The are special
pin removal tools though I've done it with a tiny jeweler's screwdriver.
In addition, instead of installing a new harness with the DCI, you could scavenge two pins from a generic adapter harness
and add them in the appropriate spots in the one that's already spliced to your headunit's harness. An advantage of this
strategy is that you can clean up your wiring and see if that fixes your existing DCI, and if not, you can buy a Modifry
without a harness and only splice the few wires that go to it.

 

Ah ok, I've got the modifry wired DCI on order with the adapter harness.

So I learned a couple things today. The good news is, the OEM harness wires weren't cut.


They were stripped in the middle and then spliced into without solder/crimps (just tape). This leaves me with two issues:

1. Cleaning the electrical tape goop off the wires.
2. How to reinforce/protect the exposed conductors.

I have no idea where to start with #1. Googone just seems messy. #2 I was thinking of flowing some solder onto the conductors and then heatshrinking a layer or two. Any other ideas?

The next thing I learned is that the ebay reverse harness connectors don't have the second lock on the connector that allows you to pull the pins out for repair. The ebay generic harness is a single piece molded connector. I'll need to remove the pins to slide the heatshrink over.

 

To clean up the wires, I'd try something simple like rubbing alcohol, but I wouldn't
obsess to much about it as it shouldn't cause any problems. Assuming the copper strands
are in pretty good shape (as they look in the picture), I wouldn't worry about adding
solder - I'd remove the pin from the blue connector and shrink on a 2" piece of heat
shrink and be done with it. With Modifry's adapter harness you won't need to scavenge
any extra pins/wires, nor does it look like you'll need to replace any in the car's harness,
so you should be all set.

 

Repair is complete. I'm back to a clean slate waiting for the modifry kit to come. Used 3:1 1/8" heatshrink with thermoplastic adhesive and then topped off with 2:1 1/8" colored tubing. No doubt about the strength of the insulation now.