Legacy Wagon 4WD F4-2.2L SOHC (1991)
Engine Control Module: Description and Operation
Computerized Engine Controls
PURPOSE
The ECU is a computer that calculates signals from various sensors and switches to judge engine operating conditions and sends output signals to
provide precise control and functioning of various systems. Main ECU control functions are:
^ Fuel injection control
^ Ignition system control
^ By-pass air control (idle speed control)
^ Canister purge control
^ Radiator fan control
^ Fuel pump control
^ Air conditioner cut control
^ Self-diagnosis function
^ Fail-safe function