Common technology

Changes in electronics technology and manufacturing methods take place rapidly and for some years now,microcontrollers (mini-computers) have formed the heart of many of the control systems found on motor vehicles. Microcontrollers, in common with other computers, contain a control unit and presumably in order to avoid any possible confusion, the ‘black box’ that used to be known as the Electronic Control Unit (ECU) is now commonly referred to as the Electronic Control Module (ECM). In this book, the term electronic control module (ECM) is used when referring to the control module that was formerly known as the ECU. As vehicle systems have developed it has become evident that there is a good deal of electronic and computing technology that is common to many vehicle electronic systems and this suggests that there is good reason for technicians to learn this ‘common technology’ because it should enable them to tackle diagnosis and repair on a range of vehicles. Indeed, many manufacturers of automotive test equipment are now producing equipment which, when supported by information and data about diagnostic trouble codes (fault codes), provides the knowledgeable technician with the support that should enable him/her to go forward in to the 2000s with a degree of confidence in their ability to maintain and repair modern systems. We will now look at a representative selection of commonly used modern systems in order to enable us to ‘tease out’ the common elements that it will be useful to learn more about.