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PCM Fail-Safe Function

Fail-Safe Function
When a malfunction occurs within the Sequential Multiport Fuel Injection (SFI) system, the Powertrain Control Module (PCM) maintains control over the fuel injector, Idle Air Control (IAC) valve etc., on the basis of the calculated values and/or backup programs stored within the PCM.

This function is called the Fail-Safe Function. With this function, a certain level of engine performance is available even when a malfunction occurs, thereby avoiding complete loss of engine performance. The systems covered are as follows:
^ The Engine Coolant Temperature (ECT) sensor.
^ The Throttle Position (TP) sensor.
^ The Mass Air Flow (MAF) sensor.
^ The Central Processing Unit (CPU) in PCM.
^ The Fuel Level sensor.
^ The Vehicle Speed sensor.
^ The Closed Throttle Position (CTP) switch.
^ The Barometric Pressure sensor.