It was also intended to improve quality and reliability and to consume less power and occupy less underbonnet space than previous engine management systems.

The "Modular" characteristic of the ECU was represented in the hardware design, which featured a common core with multiple optional add-on modules.

[citation needed] Like other electronic engine management systems, MEMS reads data from a number of sensors and computes an appropriate fueling rate and ignition advance/retard.

The MEMS firmware also features a limp-home capability (referred to in the literature as "limited operating strategy") that will substitute a nominal value for any non-operative sensor.

[1] Crankshaft position and speed are determined by input signals generated by poles in a magnetic reluctance disc.

Some operating parameters are learned by the ECU over time, such as the optimal IAC valve position for a stable idle.

[2] There are now various open and closed source applications for PC and mobile phones in order to interact with these ECUs, rather than having to purchase an old Testbook tool.