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Computerized Engine Controls (CEC)



Many components of the emission control system are monitored for proper operation by the Electronic Control Unit or ECU. In the event improper operation is detected the ECU will store an error code or codes indicating which component has failed to operate correctly and light the Malfunction Indicator Light. The diagnostic codes can be extracted to assist in diagnosis and testing of emission control system failures. Be sure to extract diagnostic codes before disconnecting the vehicle battery or the codes will be lost. (The diagnostic codes will not be lost if battery power is restored to the ECU in less than ten seconds.) The Malfunction Indicator Light is cleared when the ignition is turned off and will only light again if the malfunction is once again detected. If the malfunction returns to normal during operation the light will also turn off.


"CHECK ENGINE" LIGHT (Malfunction Indicator Light):





MALFUNCTION INDICATOR LIGHT

The Malfunction Indicator Light monitors the following items:

Engine Control Unit (ECU)
Oxygen Sensor
Air Flow Sensor
Intake Air Temperature Sensor
Throttle Position Sensor
Engine Coolant Temperature Sensor
Motor Position Sensor
Crank Angle Sensor
Top Dead Center Sensor
Barometric Pressure Sensor
Injector
Fuel Pump
Exhaust Gas Recirculation (EGR)