The Engine Control Module calculates ignition and fuel requirements. It also controls the engine actuators and provides inputs to other sub-modules for controlling and optimizing drivability, emissions systems, fuel trim and economy. The ECM receives data inputs from other control modules and sensors. On most powertrains, the ECM is also responsible for the vehicles charging system. The Engine Control Module receives its power input from the vehicle’s battery and ignition switch. It generates signals and provides a regulated 5-volt power supply form many sensors and actuators.

Engine control features include:

• Coil-on-plug ignition
• Mass airflow sensor
• Sequential Port Fuel Injection
• Direct Fuel Injection
• Variable Valve Timing
• Variable Valve Lift and Cylinder deactivation (Valve Pause Systems)
• Electronic Throttle Actuator Control (TAC)
• Air/Fuel ratio sensors
• Oxygen (O2) sensors
• Data communications bus
• Anti-theft immobilizer system
• Natural vacuum leak detection EVAP
• On-board refueling vapor recovery (ORVR) systems

The vehicle’s control system software and OBD diagnostic procedures stored in the ECM can be evaluated with a scan tool. When installing a new module, factory supplied calibration files can be updated using PC-based interface software.