ABSTRACT

Electronics invaded the engine compartment of automobiles in the early 1980s. The introduction of engine control modules (ECMs) improved the performance of automobile engines and decreased pollutant emissions. Engine tune-ups virtually disappeared. In the three decades since the first ECMs, development has continued and all aspects of engine operation and performance have improved. Figure 7.1 shows an example of one engine compartment and ECM on a recent model automobile. Electrical, mechanical, and software engineers all participate in the

development of ECMs. The design cycle for an ECM usually takes about 2 years; it continues for about 5 years after the first model introduction with various upgrades and improvements. Source code for the ECM is then archived and preserved for at least 10 years after the last unit is produced; this action is required by government regulations in the event of a recall that requires reprogramming the ECM. With more performance being squeezed out of internal combustion

engines and environmental concerns growing, the design of ECMs will increase in importance. The recent introduction of hybrid vehicles only further emphasizes the importance of the ECM-now it’s not just the control of the internal combustion engine; it also involves the entire power train, inverters, power electronics, battery control modules, motor controllers, and energy/power management through the electric motor and batteries, as well (Figure 7.2).