I like the first five chapters. No other books come close in cracking them so excellently and I don't think there are any flaw up to this point. Pinpointing the culprit on a basic car electrical system is no longer an intimidating task. Both theories and hands-on parts of the book contributed in making a better technician. Explanation of multimeters is beyond in-depth, the author went further by providing assistance in choosing a meter based on task at hand.
Chapters 6 and 7 are complex and this is where the bad things shows up. Readers are forced into brain spueezing, but still equipped with comprehensive elaboration. But I believe they can be a painless lesson with slower pace and more emphasis on comprehension.
Chapter 8, probably being a simple subject, is identical in quality to the opening chapters. Chapter 9 is easy to understand but don't provide enough detailed inner workings. It merely tells to look for a voltage drop here and there.