Need Help with harness mismatch problems

My friend has a 2004 Mustang GT. He bought a Kenwood DVD fixed screen unit and had installed by Audio Express. His car was broken into and had the Player stolen(had viper alarm that never went off??!!). I have installed stereo systems quite a few times including amps and subs so I have pretty good experience. My friend asked me to help him put the stock stereo 6 disc changer back into the car. Simple enough?? Well to my suprise........Audio Express CUT the stock harnesses off of the car!!! They didn't even offer the harnesses kit. I was pissed and it wasn't even my car. That is rediculious. Anyway......here is the problem:

There is a harness with the red front on it that comes all the way from the main wire bundle behind the dash of the car. I thought that it was the harness that was spiced for the Kenwood. However.....there is no splicing (i promise). So I figured that it was the stock harness. But it does not fit into the back of the stereo. Is there an adapter for the Mach stereo systems?? I found a "replacement" harness for the mustang and it looks similar to what is already there (pic 4). I included pics of products I found and the harness that is in the car(no splices). The small cut harness sitting on the back of the stereo does fit into the slot. That is where we found it. Any help is very much appreciated.

 
Ok......that does look like the proper harness for the radio but that would make me have to cut the OEM harness that is there. What does the OEM setup look like. Was there an adapter. Im confused at all of this. I am guessing since it is an upgraded (mach system) OEM stereo that it needs an adapting harness. If someone could shed some light on this it would be appreciated. Thanks.......

 
I could be wrong, but my guess is that the plug you found in the vehicle is a "bypass" harness. Lots of Fords with amplified systems have them behind the radio; it's the harness that would be used if the vehicle had a non-amplified system. I haven't seen one of that type before, but it clearly wasn't plugged into the original radio and it looks like a radio harness, right down to the twisted speaker wire pairs. In a Mach system, bypass harnesses are usually tied into the tweeters.

I thought you said the original plugs were cut off and the Kenwood harness wired in? If so, you should be able to cut off the Kenwood plug again and rewire the replacement harness back to the stock wires. The only tricky part might be matching the wire colors, since the aftermarket harness won't match the factory wires, but you have (I assume) the Kenwood harness for a guide.

 
Well......The smaller plug was cut. From what I can tell, the red plug in the picture is the original plug. But like you said.....it is for the standard radio. I am guessing that the upgraded mach systems have an adapter that converts the red faced plug to two different ones that alows for the external OEM amps. Then the smaller plug is universal among both systems. I just need to get that adapter assuming I am correct.

 
I don't think I agree with your guess. I think the red plug you found was never plugged into anything. That's the way Ford bypass plugs often work. I've never seen a Ford factory plug running to a socket connected to a completely different Ford factory plug. What would be the point?

Question: What wires were the Kenwood wires connected to? The small cut plug you found doesn't contain all the original power and speaker wires. Most likely they cut off the larger plug just like they cut off the little one, and connected the Kenwood wires to it. There's no "adapter" that connects the factory radio to that plug you found buried in the dash.

 
The red plug found that I am holding in the picture is the only plug behind the dash aside from the cut plug. It has no splices and was not cut. I will assume for a moment that it was not plugged into anything as you say. I believe that the kenwood harness was taken with the radio. So that would mean that the smaller plug is the only one that was connected which was cut. What about the radio though.....it has slots for 3 plugs...

View attachment 5463

the red arrow is the plug in question

the blue arrow is the cut wires

the purple arrows are some misc cut wires including the ground

and the green arrow is not part of the stereo ( just in case someone brings it up)

View attachment 5460

A closer look at the cut wires

From my experience in installing......I don't see enough wires (assuming that the color codes are not the standard) to include speakers, power, remote, etc.

I talked to the radio repair guy for ford and he was just as confused as you. I swear that I am not an idiot. He said there is no adapter and that it should just plug into the back of the stereo as I have seen many times. This is different for some reason. What about the 3 plug repair harness?? Things are not adding up any way I look at it. Anyone have a haynes manual for the car.....if its even out......

 
I'm at a loss, too. It's hard to tell how many wires are in that cut cable that you're holding in the second picture. Also, I wouldn't mind a closer look at whatever the green arrow is pointing at.

Usually you'd only find two plugs at the back of the factory radio; the smallest and the largest. The middle plug is for a separate aux source like a CD changer, which your vehicle isn't equipped with. The smallest is the signal/remote feed for a factory amp, which might be just for bass. I bet the RCA cable was originally plugged into the aftermarket subwoofer output. But that black plug seems completely out of place, and I don't see the main power/ground/speaker plug.

 
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