Electrical schematic??

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Joined
May 15, 2011
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1971 Mach 1 Mustang
Hey guys just wondering if anyone has an electrical schematic for our cars?? I have the ford 5 volume books but cant find any wiring diagrams in it??? I just had my tach rebuilt by rocketman, and while looking through my under dash wiring i found a melted wire. The red/green one. Its melted at the base of the steering column. I was wanting to trace it and find out where all it goes. So i was gonna use the diagram to get an idea where im looking. Im wondering if this is what was causing my miss last summer?? It would miss every once in a while then just run fine. Then be driving along and no miss but it would just shut off??? Turn key off then back on and it would fire up like nothing ever happened. Crazy electrical stuff. But i believe the red/green originally went to the tach, but it was long ago cut out but not sure what they did with the wires cause i cant find them. And if i remeber right that is what ran the ignition coil on a stock motor. So i have some wire tracing to do. Any help would be great, if someone has a copy on their computer or if someone could scan one it would be greatly apprieciated. Want to get this all figured out before i drop the new 408 in it. THANKS!!! Kevin

 
red/green went to tach and out to coil. it is part of the resistance wire circuit that drives the points in the distributor.

 
Thanks guys thats what i was looking for. I will check it out when i get home. hard to see on an i phone! So if the red/green went to the coil and points, i shouldnt really need it then since im running an msd box and electronic msd billet dizzy??? As long as im not getting my power for the tach or the msd box from that red/green wire i should be ok. That wire may have been messed up for years, but i just noticed when i was under there messing with my tach. Just want to trace it and follow it to make sure it didnt ground out onto any other wires and melt them.

 
The tach, if I am remembering correctly, uses that wire to correctly function. Did your tach work before? The tack uses the firing of the points to create kind of a pseudo-pwm signal that drives the needle. If your tach worked before I'd say splice in new wire and make it pretty (if it ain't broke don't fix it) if your tach doesn't work this could be part of the problem

 
My tach was working but I had it wired to a msd tach adapter and my msd box. The red/green wire runs over to the cylinoid for the I terminal I believe. So if it's melted under the dash it could be grounding out once in a while and shutting the motor off. I will do some wire tracing. And might just run a new power wire to the cylinoid. That way I completely get rid of the red/green wire circuit. Hopefully that will fix my problem.

 
Sounds like it should help if nothing else! I had thought you may have had an aftermarket solution to the tach already. I had a similar problem where my brake switch had gotten pinched by the steering column and was shorting out whenever I would hit the brake.

 
I just got my tach back from rccinnovations so I won't need the msd tach adapter anymore. So if anyone needs a tach adapter let me know. If you install an aftermarket ignition system in your car and your stock tach no longer works then you need a tach adapter. I might even post it up on a separate thread.

 

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