If you've ever tried to chase down an electrical gremlin in a classic Mustang, you know that sinking feeling when you're staring at a bundle of wires that all seem to blur together. The 1966 Mustang's electrical system, while relatively simple by today's standards, can still throw plenty of curveballs when you're trying to diagnose a problem or complete a restoration. That's where the 1966 Colorized Mustang Wiring Diagrams manual becomes absolutely invaluable.
Why Colorized Diagrams Matter More Than You'd Think
Here's something that'll resonate with anyone who's worked on vintage Fords: original factory diagrams were black and white. When you're under the dash trying to identify whether you need the blue wire with a red stripe or the red wire with a blue stripe, those monochrome schematics aren't doing you any favors. This manual, published by Forel Publishing Company under license from Ford Motor Company, transforms those cryptic line drawings into color-coded roadmaps that actually match what you're seeing in front of you.
The manual spans 24 pages of electrical illustrations compiled directly from original Ford technical publications, covering everything from basic lighting circuits to the more complex power top mechanisms. It's not just about pretty colors—it's about reducing diagnostic time and avoiding the kind of mistakes that can turn a simple repair into an electrical nightmare.
Understanding the Wire Identification System
One of the most practical features you'll find is the comprehensive wire identification table listing numbered wires from 2 through 122. Each wire is documented with its specific color code and source form reference (primarily Forms 7795-66 and 7760-66). What's particularly interesting is how certain color combinations repeat throughout the system—like the 12 variants of wire 19 series, all in blue-red stripe configurations. This isn't random; it indicates parallel circuits or redundant connections that were part of Ford's electrical architecture.
The manual also includes something crucial that many enthusiasts overlook: a note explaining that if your wire colors don't match what's shown on a particular diagram, you should check other diagrams in the manual for alternative matches. This acknowledges the reality of mid-year production changes and regional variations that Ford implemented during the '66 model year.
More Than Just Pretty Pictures
What sets this manual apart is that it doesn't just throw diagrams at you—it teaches you how to read them properly. Included in the manual is material from Ford's own training program (Course 13001, Vol. 68) titled "How to Read Wiring Diagrams." This section emphasizes a diagnostic approach that's still relevant today: thinking like a doctor who identifies root causes rather than just treating symptoms.
The legend section defines all the standard electrical symbols you'll encounter—capacitors, batteries, switches, relays, motors, and various connection types including splices, junctions, and crossovers. It also clarifies switch terminology like N.O. (normally open), N.C. (normally closed), and the various pole-throw configurations (SPST, DPST, SPDT). If you've never been formally trained in reading electrical schematics, this foundational knowledge can transform you from someone who's guessing to someone who actually understands what they're looking at.
The Bottom Line for Mustang Owners
Whether you're troubleshooting a charging system that's acting up, installing period-correct accessories, or doing a complete electrical restoration, having accurate, color-coded diagrams isn't just convenient—it's essential. The 1966 Colorized Mustang Wiring Diagrams manual gives you factory-accurate information in a format that's actually usable in real-world repair situations. It's the difference between spending hours tracing wires with a multimeter and quickly identifying exactly which circuit you're dealing with.
