The business of automotive repair and the work of the auto mechanic have changed greatly in recent years. Driven by the need to reduce harmful emissions and increase fuel economy, vehicles are becoming increasingly electronically controlled. The work of vehicle repair which once consisted mostly of disassembling and repairing mechanical components is now becoming increasingly the work of computer diagnostics.
The U.S. government first began looking at environmental pollution from vehicle emissions in the mid 1960s, and the first fuel efficiency standards for passenger vehicles were passed in 1975. The earliest means of controlling vehicle emissions were mechanical devices aimed at containing fuel vapors and limiting pollutants from the exhaust pipe. These systems had limited effectiveness. To meet increasing fuel economy standards in the late 1970s and early 80s vehicle manufacturers also needed to more precisely control engine combustion. They did this through the use of computerized engine control. Simple electronic fuel injection systems had been used in a few vehicles beginning in the 1960s, but when increasingly complex electronically controlled fuel and ignition systems became standard equipment on vehicles twenty years later, the world of automotive repair began to undergo a dramatic shift.
The earliest electronic engine control units were simple circuit boards used to meter fuel more precisely and adjust ignition timing for optimum engine performance and efficiency. Today, cars and trucks may have dozens of individual control devices, or computers, to operate and monitor the various functions of the vehicle. The decreasing size and cost of microprocessors as well as the sensors that monitor vehicle operations led to their rapidly increasing use in automotive applications. Since their start as a way to meet increasing fuel economy and emissions standards, computers now operate nearly every system of the vehicle. From engine and transmission control to brakes and steering systems to cabin climate, power seats and mirrors, computers control all aspects of vehicle operation in order to maximize fuel economy, safety and comfort. With the recent popularity of hybrid-electric models and the reintroduction of electric vehicles, the complexity of vehicle electronic systems is now developing even faster.
Auto repair and maintenance has become a business employing technicians skilled in operating computerized tools to interface with the complex electronic systems of modern vehicles. A tool box full of wrenches and hammers now also contains a laptop computer or handheld scan tool along with the many other scopes and meters that are necessary to diagnose problems with vehicle systems. The diagnostic data of the control modules in cars and trucks is accessed using handheld scan tools or PC-based interface units.
Working with all of these systems has changed the auto mechanic into an electronics technician.