Self-Diagnostic System: Notes

The PCM diagnoses any troubles which may occur in the engine control system when the ignition switch is in the ON position with the engine running. The PCM indicates a malfunction by illuminating the Malfunction Indicator Lamp (MIL) when a fault occurs in any of the following systems:

• The fuel control heated oxygen sensors.
• The catalyst monitoring heated oxygen sensors.
• The Engine Coolant Temperature (ECT) sensor.
• The Throttle Position (TP) sensor.
• The Mass Airflow (MAF) sensor.
• The Vehicle Speed Sensor (VSS).
• The Intake Air Temperature (IAT) sensor.
• The Manifold Absolute Pressure (MAP) sensor.
• The Camshaft Position (CMP) sensor.
• The Crankshaft Position (CKP) sensor.
• The Evaporative (EVAP) emission control system.
• The Idle Air Control (IAC) system.
• The misfire detection.
• The fuel trim.
• The catalyst monitor.
• The cooling fan control.
• The Central Processing Unit (CPU) of the PCM.

When the PCM detects a malfunction in one of the above areas, the PCM will illuminate or flash the MIL in order to notify the driver of the occurrence of a fault. The PCM will store a Diagnostic Trouble Code (DTC) when PCM illuminates the MIL. The PCM will turn OFF the MIL after 3 consecutive ignition cycles, in which the diagnostic runs, without the malfunction occurring. The DTC will remain stored in the PCM memory after the MIL is OFF.