Fail-Safe Function
FAIL-SAFE FUNCTIONWhen a malfunction occurs in the electronic engine control system and is detected by the engine control module (ECM)/powertrain control module (PCM), the injectors, idle air control (IAC) valve and other major components are supported or compensated for by signals from a program stored in the ECM/PCM to sustain minimum driveability until repairs to the electronic engine control system can be performed.
This function is called the "fail-safe function." This function provides a minimum level of engine performance which is available even when failure in the electronic engine control system occurs.