Computers and Control Systems: Description and Operation

PURPOSE/OPERATION
The Mitsubishi electronically controlled multipoint injection system maintains emission levels and fuel economy within government agency standards, while optimizing driveability. The system consists of an electronic control unit, control relay, wiring, sensors and actuators. The ECU uses an 8-bit microprocessor, random access memory, read only memory and an Input/Output interface. The control relay supplies positive current to the purge solenoid, ECU, and injectors. It also supplies current to the fuel pump during starting. The system also performs self-diagnostic procedures and provides back-up functions if certain circuits fail.