Engine Control Module

The Engine Control Module (ECM) operates the fuel system. It regulates ignition timing, air fuel ration, emission control devices, charging system, idle speed control, air conditioning clutch engagement, etc. The ECM has the ability to adapt to changing operating conditions.

The ECM receives input signals from various switches and sensors. Based on these inputs, the ECM regulates various engine and vehicle operations through different system components also known as ECM Outputs. On the other hand, the sensors and switches that provide inputs to the ECM are ECM Inputs. For example, the ECM adjusts ignition timing based upon inputs it receives from sensors that react to: engine RPM, engine coolant temperature, throttle position, transaxle gear, vehicle speed, etc. The ECM adjusts idle speed based on inputs it receives from sensors that react to: throttle position, vehicle speed, transaxle gear, etc.