3 Copyright by Goodheart-Willcox Co., Inc. Automobiles and light trucks are now as much “electronic” as they are “mechanical.” Look under the hood of any late-model car and you will fi nd a maze of wires connecting dozens of devices. In fact, electronics can be found in almost every major system of a car, including the suspension, transmission, fuel, ignition, emission control, and braking systems. Some cars have four or fi ve separate on-board computers. The day of the “backyard mechanic” is over this is the era of the well-trained electronic technician. Conventional electrical systems, when combined with newer computer-controlled systems, make it necessary to have a sound background in electricity and electronics. This knowledge will allow you to do competent repair work. Anyone versed in auto electronics will have no problem finding and keeping a good job in the automo- tive service industry. Auto Electricity and Electronics was designed to make the complex seem simple. Short sentences, abundant illustrations, and easy-to-follow procedures are used to make learning easier and more fun. All technical terms are printed in bold italic and clearly defi ned so that you can quickly learn the “language” of the automotive electronic technician. Th ere are three types of special notes you will encounter in this book: Note: A note may highlight important technical information, present information related to the topic, or cross-reference the material. Caution: A caution identifies a situation that may result in damage to the vehicle, tools, or equipment if the proper procedure is not followed. Warning: warning identifies operations that may potentially result in injury. Th e text is divided into 36 chapters that are grouped into four sections. Th e fi rst section reviews fundamentals: electrical principles and components, electronic compo- nents, wiring repairs, soldering, wiring diagrams, special tools and equipment, basic electrical tests, and safety. Th e second section summarizes the construction and opera- tion of major electrical/electronic systems. Th e third sec- tion explains how to diagnose and repair these electrical/ electronic systems. Th e last section contains ASE and career information, useful tables, a glossary, and index. Each chapter starts with Learning Objectives so you know what you are expected to learn in the chapter. Technical Terms are also given so you can make sure you grasp new technical words. A Summary at the end of each chapter allows you to quickly review the most important topics. A good mix of Review Questions allows you to deter- mine how well you understand the material in the chapters. A separate section of ASE Certifi cation-Type Questions is presented at the end of each chapter to help you prepare for the types of questions that will be encountered on the ASE Certifi cation Tests. Introduction