2.2L Systems/Tests W/Codes: Operation: Notes
The engine control system consists of the ECA, sensors, switches, and actuators. In order for the ECA to perform properly, it must be kept constantly informed of engine operating conditions.
It is the task of the engine sensors to supply the ECA with specific information, in the form of electrical signals, required to determine engine operating conditions. The ECA sends out electrical signals to control air/fuel ratio, emission controls, idle speed and ignition timing. In the event of a sensor or actuator failure, the ECA initiates an alternative strategy to allow the vehicle to maintain driveability. This strategy is called Failure Mode Effects Management (FMEM). It substitutes a fixed sensor signal and continues to monitor the failed sensor. If the failed sensor signals return within operating limits the ECA will again use the sensor's signal. The "Check Engine" light will remain on when FMEM is in operation. The FMEM strategy is listed in the SERVICE CODE DEFINITIONS CHART. Individual component operation is as follows: