OBD-II Bi-Fuel Drive Cycle Description
WARNING: This page is about a different car, the 2002 Ford Pickup and 2002 Ford Cab & Chassis. However, it is still accessible from the selected car via links, so may be relevant.
OBD-II drive cycle is a pattern of driving in which the PCM will execute all OBD-II diagnostic monitors. Drive cycle is used to detect first time faults, so that a DTC will be stored in compuvalve memory. When the same fault is detected in two consecutive trips or if fault is emission related, compuvalve uses the trip information to decide on whether to illuminate the Malfunction Indicator Light (MIL) will illuminate.
MIL will go off when the fault condition no longer exists or the vehicle is driven 2 miles with no fault. MIL will also go off if the vehicle switches automatically to GAS mode. DTC will be stored in compuvalve memory until vehicle has completed 40 drive cycles without repeat of fault.