Trip

The ability for a DTC to run depends largely upon whether or not a Trip has been completed. A Trip for a particular DTC is defined as vehicle operation, followed by an engine off period and a driving mode such that any particular DTC has had sufficient time to complete testing. The requirements for trips vary as they may involve items of an unrelated nature; driving style, length of trip, ambient temperature, etc. Some DTCs run only once per trip (e.g. catalyst monitor) while others run continuously (e.g. misfire and fuel system monitors). If the proper enabling conditions are not met during that ignition cycle, the tests may not be complete or the test may not have run.