When I dove into my dash to replace the dash lights, I quickly found that the electrical system was a 50 year old mish mash of twisted connections and electrical tape. As an electrical engineer, 
I could not live with this and so I decided to upgrade most all of the wiring. For the main harness, I selected the 1966 UNDER-DASH HARNESS W/ PREMIUM FUSE BOX AND RELAYS from CJ Pony Parts with blade fuses. To my chagrin, when I opened the box there was NO CIRCUIT DIAGRAM. After several queries to CJ’s customer service with no results of value, I called Scott Drake, the manufacturer, directly to enquire about a circuit diagram. Scott wasn’t available but one of his employees told me that there was no specific diagram for this harness but that the classic diagram would work ok - for the small price of $12.95.
I figured I could easily find a circuit diagram on line so I asked Google to find one for me. Google came through and I found a number of black and white diagrams but no color. So I decided to fix the problem myself. First I took an old overall b & w schematic that was divided into two pages. I “welded” them together and imported the combined jpeg into AutoCad. I spent most of a day developing a couple of lisp routines, one to draw multicolored lines and another to label them with the Ford numeric legend. I then spent another couple of days digitizing the schematic. After realizing that the schematic I had did not agree with the earlier versions, I spent another day truing up the overall schematic.
(If you run AutoCAD, including later versions of LT, BricsCAD or any other CAD program that supports AutoLISP, let me know via the Contact Me and I will send you the routines.)
I then took the copy of the classic wiring diagram, the new harness and a circuit tester and had at it. While the classic diagram is close, there are a couple of additional relays and a few subtle but significant changes in the wire colors. So much for Scott’s advice. (I know a real wiring diagram exists somewhere because the harness could not be made without it.) When I was done, I had a complete set of colorized wiring diagrams which I now share with the world.
TO DOWNLOAD THE PDF FILE, click one of the images below to open the pdf in a new tab and then click the Download icon in the upper right. If you just want to download the single image, right click the image and then click Save image as... or Copy image.
NOTE: If you have downloaded earlier versions of the 64-66 diagrams, I have spent some time updating and correcting them. This includes revising the linetypes and colors to make them more readable both on screen and printed.
I have added 67-72 diagrams. However, only the 67 and 68 diagrams have the supporting detail drawings. If these exist for the other years, please send them to me, I will gladly colorize them and add them to the downloadables. Also, beginning with the 69 schematics, many of the line colors are not labeled. If someone will send me the correct colors, I will correct those drawings.
You may also notice that I have mirrored the original schematic vertically so that the headlights are on the left and the starter relay is at the top. I found it annoying when I was flipping between the detail sheets and the schematic that they were not oriented the same. I hope you agree with me.
I'd love to know if you found these diagrams useful and, if you'd like, to share a brief description of your project. And with your permission, I might even show some of the comments on the page. Please click here to . And if you have any questions or suggestions or if you find any errors in the diagrams, please use the Contact button.
I get comments from all over the world. To view some, click on .
While I am dedicated to providing all content on my site for free, if you would like to support my efforts in this and other projects, a small donation is appreciated.
I could not live with this and so I decided to upgrade most all of the wiring. For the main harness, I selected the 1966 UNDER-I figured I could easily find a circuit diagram on line so I asked Google to find one for me. Google came through and I found a number of black and white diagrams but no color. So I decided to fix the problem myself. First I took an old overall b & w schematic that was divided into two pages. I “welded” them together and imported the combined jpeg into AutoCad. I spent most of a day developing a couple of lisp routines, one to draw multicolored lines and another to label them with the Ford numeric legend. I then spent another couple of days digitizing the schematic. After realizing that the schematic I had did not agree with the earlier versions, I spent another day truing up the overall schematic.
(If you run AutoCAD, including later versions of LT, BricsCAD or any other CAD program that supports AutoLISP, let me know via the Contact Me and I will send you the routines.)
I then took the copy of the classic wiring diagram, the new harness and a circuit tester and had at it. While the classic diagram is close, there are a couple of additional relays and a few subtle but significant changes in the wire colors. So much for Scott’s advice. (I know a real wiring diagram exists somewhere because the harness could not be made without it.) When I was done, I had a complete set of colorized wiring diagrams which I now share with the world.
TO DOWNLOAD THE PDF FILE, click one of the images below to open the pdf in a new tab and then click the Download icon in the upper right. If you just want to download the single image, right click the image and then click Save image as... or Copy image.
NOTE: If you have downloaded earlier versions of the 64-
I have added 67-72 diagrams. However, only the 67 and 68 diagrams have the supporting detail drawings. If these exist for the other years, please send them to me, I will gladly colorize them and add them to the downloadables. Also, beginning with the 69 schematics, many of the line colors are not labeled. If someone will send me the correct colors, I will correct those drawings.
You may also notice that I have mirrored the original schematic vertically so that the headlights are on the left and the starter relay is at the top. I found it annoying when I was flipping between the detail sheets and the schematic that they were not oriented the same. I hope you agree with me.
I'd love to know if you found these diagrams useful and, if you'd like, to share a brief description of your project. And with your permission, I might even show some of the comments on the page. Please click here to . And if you have any questions or suggestions or if you find any errors in the diagrams, please use the Contact button.
I get comments from all over the world. To view some, click on .
While I am dedicated to providing all content on my site for free, if you would like to support my efforts in this and other projects, a small donation is appreciated.
