Section 254 (Engine Controls - Theory & Operation - 2.2L): Self-Diagnostics: Description: Trip
WARNING: This page is about a different car, the 2003 Pontiac Sunfire, 2003 Pontiac Grand Am, 2003 Oldsmobile Alero, and 2003 Chevrolet Cavalier. However, it is still accessible from the selected car via links, so may be relevant.
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).