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Mod Motor Wiring in General

whiteponygt

Well-Known Member
So let s be clear you used the full 03 cobra harness including the 03 dash harness, or did you use the Fox dash harness and 03 cobra engine harness? Need more details also you said you hooked up what you thought you needed to run the Fox dash. I used the 96 cobra harness and spliced my Fox ends .knowing what I know now that method is like trying to put a square peg in a round hole.it was 3x the work of building your own harness.
 

FuturaGuy

Well-Known Member
Staff member
I also showed it drawing 2.6 amps when hooked up which seems to be quite high which means to me that it has a direct short of some sort.
Not knowing how much of your Fox wiring you kept and what parts of the Cobra wiring you're using, it's hard to troubleshoot your problem by e-mail. I'd suggest you take one fuse at a time out of the dashboard fuse box and each time test the positive terminal to ground for continuity. That may help to isolate the circuit with the short. Disconnecting each individual ground and testing for continuity will further identify the short circuit.

There is one far-out difference between Foxes and SN-95's that will cause problems if you're not aware of it. In an SN-95 Mustang, the low coolant light gets its power from the fuse box, the current goes thru the bulb, to the switch, and then to ground. In a Fox 5.0 GT, the power goes from the fuse box to the bulb and then to a relay under the dash. There is a parallel circuit that provides current directly to the low coolant switch and from there back to the relay. When the switch is closed it triggers the relay to ground the low coolant light circuit and the light goes on. The wire coming back from the switch to the relay is light blue, and if you connect that wire directly to ground, you have a short circuit when the coolant light switch closes. That may not be your problem but it's something to check.
 

whiteponygt

Well-Known Member
When wiring mine I learned the Fox uses allot of modules to power everything . I had to wire one in for rear defrost,had to add relays for the turn signals. Make a harness for my power mirrors,splice in taillights harness. That was all to keep Fox interior with sn harness.oh btw I had a wiring issue with my lights I worked on for about 3 days turns out Ford changed bulbs from the Fox to the sn. They switch pins on tthe low beam and ground. I had Fox bulbs in and it was feeding back threw the ground
 
I have put the entire 04 harness setup in the car. Everything for the fox has been removed. The full body harness out of the 04 is now in the car including dash harness. I was trying to use the fox ignition switch, light switch and multifunction switch so I repined the things that were needed for that using info from the wiring diagrams and resources from this forum. Unfortunately I have spent a ton of time chasing my tail to try and find this problem and I have even taken the dash out again to verify it was all wired correctly. It seems from the testing that all of the problem circuits are in the dash area. I am not with my notes right now so I cannot give you the exact fuse locations but they involve things like the daytime running lamps, instrument cluster, CCRM, and fog lights. I pulled every fuse out and checked each circuit and these are the ones that are showing continuity. I will get the exact fuse locations ASAP so that you can see exactly what is involved. I am almost to the point of putting all of the Fox wiring back in the car and starting over. It has the upper hand at this point.
 
The Fuse locations in the CJB that are showing continuity to ground are as follows. F2.5, F2.13, F2.24, F2.27, F2.34, F2.37, F2.39, F2.41. I am sure that you have a breakdown of those locations in the fuse box so I will spare the listing of all of these circuits unless you would like it. F2.37 is showing continuity on both terminals. This has me totally stumped but I know that it is just something simple that I am missing or at least I hope.
 

whiteponygt

Well-Known Member
Do you any diagrams showing how u 're pinned or an pictures. I have the service Manuel for a 97 cobra and I will say there are some differences I've noticed from listed diagrams vs the factory Manuel on this site. Ford is famous for changing a pin location or wire color for one year to the next on certain things.
 
I can get together all of the drawings that I used but it will take me a bit. I want to ask because I do not mind backing up if it is better. Should I cut my losses and go full fox body harness and run the sn harnesses in front of the firewall. I just want to move this forward ya know. Thank you for you help
 

whiteponygt

Well-Known Member
To answer that question all depends on ur plans I ran the 96 body harness because I wanted keyless entry . I'm sure you can wire it in to the Fox but you have to tie into the horn, lights ,locks. if ur looking to just get it running and decent with wiring building ur own harness is probally ur best route with the Fox harness.
 
I would like your opinion on going with a new fox harness from latemodelrestoration restoration so that i have all new plugs because some of my old ones have been hot. Then run 03/04 harness in front of firewall and make a jumper. I used to think that I was pretty good at the wiring but this thing has beaten me up enough and I want total reliability. I am not concerned with having remote entry so no worries with that. Thoughts. Also my email is jackball60@hotmail.com and I would love to be able to talk either you whitepony or you futura so that I avoid issues within this path. You guys have really helped me so far and I appreciate it a ton.
 

whiteponygt

Well-Known Member
As for making the jumper harness I can tell you I attempted after working with futura,(I will tell you after talking to him he is a wiring guru)but after 3 attempts I threw in the towel I used the whole body harness from my donor and solider the Fox ends on my first attempt I had some issues as u but me and a good friend spent about a total of 2 weeks wiring in Fox features onto the 96 harness.of u want to use the cobra i can kinda walk you threw how I wired into the 96 with the Fox features but with the jumper harness your gonna have to catch up with futura
 
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