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Trip

A trip is an interval of time during which the diagnostic test runs. A trip may consist of only a key cycle to power up the PCM, allow the diagnostic to run, then cycle the key OFF to power down the PCM. A trip may also involve a PCM power up, meeting specific conditions to run the diagnostic test, then powering down the PCM. The definition of a trip depends upon the diagnostic. Some diagnostic tests run only once per trip (i.e., catalyst monitor) while other tests run continuously during each trip (i.e., misfire, fuel system monitors).