geoff17

Hey guys, I know this may not be the right forum for these questions but hoping some people here have already done this. So in preparation of my ls swap into this mustang I decided to go through the entire body harness of this car and eliminate any un-needed wiring. Where I have now got stuck is the part of the dash harness that goes out into the engine bay. I have almost got rid of every wire that went into the factory 4 cyl computer since I want the entire body harness completely stand alone and separate from the pcm wiring later. There are a few plugs that I don't know what they are for, I have googled and found no answers. 2 of the plugs I believe plugged into the engine harness so I have a feeling I won't need them but they still have 2 or 3 wires attached to them that I haven't removed when I went through cutting everything else out, if anyone knows what all came through those plugs I would appreciate it. There are also 2 plugs that were up in the front driver fender with factory plugs installed into the plug ends, not sure what these are for, any clue? I'll attach some pics here in a min from my phone.

geoff17

geoff17

geoff17

Ok so the first 2 pictures are the plugs that have factory plug ends stuck in them and am not sure what they do, the 3rd picture I'm not sure what that piece is, one the wires then goes to the plug in the 2nd pic. The 4th pic is of the 2 plugs that I believe went into the factory engine harness, the cut wires are from where I already removed inputs to the cluster such as oil pressure, temp, etc, I was able to find the cluster diagram and cut out those inputs since they won't be used with that harness, but there are still a few wires in those plugs I need to trace back and see if they are needed. The 5th pic is the 2 plugs that then plug into the headlight harness, I'm a little concerned since the smaller of the 2 plugs I already removed 2 of the wires and its only has 1 left going into it. My headlight harness also came from a v8 car (1990 still) whereas this is an original 4 cyl car. The last picture is what I believe to be the wire that would attached to the alt (yellow) the one beside it I don't know.

Thanks for any help anyone can give, wiring is not my strong side and I skipped doing all this on my last ls swapped fox.

svslow

These cars have so many extra wires that were never even used from the factory so who knows what those might be. I wouldn't worry about. Just strip it down to only what you need and it becomes very simple. I just went through and did a similar thing. Ripped out pretty much everything other than the lamps, wipers and blower.

geoff17

Thats what I have been doing, but I have been trying to understand what I am ripping out when doing so. I do have a question for you though since you have been through this process, after you had done that were there any points where you needed to re-ad a wire or a ground? My only worry with doing it the way I have already started is that as I start to rip out unused items I'm concerned that they may have also passed through to something down the line either a shared ground or a 12v source.

geoff17

No one here knows a fox and its wiring even a little? Any ideas as to what the plugs are in the first 2 pics that clearly aren't meant to plug into anything, but what are they for?

64post

iTrader: (5)

If you tear it all out, save it, you'll need it, it's nice to have the right color and gauge wires for bare minimum thing like lights, fans and inst. Get yourself a good set of wiring diagrams specific to your car.

svslow

There are tons of good diagrams here.

http://www.veryuseful.com/mustang/tech/engine/

geoff17

Thanks for the diagrams, they don't quite have the detail needed for the body wiring, which of course is the one that changed the most amongst the different years.

vinceI

iTrader: (5)

Autozones website has wiring diagrams in the tech section. I'm using them for my 99 mustang. Not all the connector pin outs are on there but there is a lot of complete diagrams from fuse to ground for things such as lights, wipers, horn etc. I was searching for diagrams with actual connector pin outs but I didn't have any luck and a factory wiring manual is over a $100. I bought a Haynes manual and all the wiring colors were wrong so I wouldn't recommend that.

zipster

iTrader: (5)

I use alldata, you can log on and pay $14 and get all the info on your specific year.

geoff17

Thanks for the info guys, I'll look into the Autozone and Alldata options. I did finally figure out what the big plug was with the cap on it, apparently its for the DRL's on canadian model cars, it plug into a DRL module for the US cars its just capped off, so now to see if I can cut some of those wires out to clean up that section of the harness.

Bowtiedford

iTrader: (9)

like stated above these harnesses will have a heck load of extra plugs. The front 2 plugs might be fog lights. my 4 cyl coupe had the GT fog light plugs

bjamick

iTrader: (31)

3rd pic looks like horn connector. The yellow wire I believe is what powers the ignition switch.

geoff17

Thanks again for all the help guys, I got them all figured out, the one in the 3rd pic was a test port for the washer tank pump, the first 2 were the DRL plug for candian cars and the washer pump plug, I removed all of these. The 2 round plugs with very few wires left were for integrating into the stock engine harness, the 2 plugs in the 4th pic one was for the headlight harness and the other was for the alternator wiring, which I removed. The yellow wire is the main 12v power source and other lone black and white wire beside it is a ground for the door harness that sits up near the top of the dash by itself kinda seperate. Hopefully this may help someone out in the future.