If you are opening this copy of Auto Brakes, you may
be taking a course on automotive brake systems, or you
may be a working technician seeking more information on
brake service. Auto Brakes is intended to give you a thor-
ough understanding of the brake systems used on modern
In the past, brake repair was a simple process, requir-
ing few special tools. Most concepts could be understood
simply by observing the brake system components. The
brake systems on modern vehicles are more complex,
making even slight defects more obvious. Diagnosis and
service requires special tool and test equipment.
To diagnose and repair modern brakes, or any part of
the vehicle, reading is a necessity. Repair information
comes in all forms of printed material including this text,
service manuals, and technical service bulletins. As a tech-
nician, you must know how to look up diagnostic proce-
dures, test specifications, and other information. You must
also know how to use a computer as more and more
service data is now provided on compact disc and on the
Internet. Understanding how computers work will also
make understanding the on-board computer systems used
on vehicles much easier.
While you will be learning to use modern test
equipment and procedures, you will also learn test pro-
cedures used since the earliest days of the automobile.
Your progress through this text will include learning
about basic hydraulic and friction principles. You will
also learn about brake electronics and computer control.
Many concepts used in the brake system were discovered
long before the automobile was developed. Other con-
cepts, such as anti-lock brakes and traction controls, are
relatively new. Both old and new concepts will be cov-
ered in Auto Brakes.
Auto Brakes has been carefully designed so that all
parts and operating principles will be fully identified and
explained before you begin work on the actual system. At
no time will you be asked to service a part of the brake sys-
tem before you are shown its theory of operation. Each
chapter of the text begins with Objectives that provide
focus for the chapter. Technical terms are printed in bold
italic and are defined when first used. Figure references
are printed in bold. Warnings and cautions are provided in
cases where a danger to life, limb, or property may exist.
Notes are provided to illustrate procedures that can make
routine tasks easier. Each chapter contains a Summary,
“Important Terms” section, and Review Questions.
One reason you may be holding this text is ASE certi-
fication. Auto Brakes covers all areas that you will be
expected to know to pass the ASE Brakes test (A5). Each
chapter has a section of ASE-type questions to help you
prepare for this test. Experienced technicians can also use
this text to review before taking the Brakes recertification
test. Chapter 24 is devoted to information about ASE certi-
fication and passing the certification test.
A Workbook for Auto Brakes is also available. It con-
tains additional questions and jobs that test your hands-on
ability. Each chapter in the workbook corresponds to the
chapters in this text.
Martin T. Stockel