Circuit Description

The engine control module (ECM) is the control center of the fuel injection system. It constantly looks at the information from various sensors, and controls the systems that affect vehicle performance. The ECM also performs the diagnostic function of the system. It can recognize operational problems, alert the driver through the malfunction indicator lamp (MIL), check engine, and store a diagnostic trouble code (DTC) or DTCs which identify the problem areas to aid the technician in making repairs. The ECM detects communication link failure with immobilizer control unit.