Engine Control Module (ECM)
The engine control module (ECM) is located in the engine room. The ECM controls the following:
- Fuel control.
- Throttle valve control
- Ignition timing.
- On-board diagnostics for engine functions.
- Valve timing
- A/C clutch control
- Cruise control etc.
The ECM constantly observes the information from various sensors. The ECM controls the systems that affect vehicle performance. The ECM performs the diagnostic function of the system. It can recognize operational problems, alert the driver through the MIL (Check Engine lamp), and store diagnostic trouble codes (DTCs). DTCs identify the problem areas to aid the technician in making repairs.