What is OBD II?
OBD II stands for "on-board diagnostics two." It is the on-board automotive diagnostics system that has been required by the EPA on every new motor vehicle sold in the USA since 1996. The on-board diagnostics system monitors virtually every component that can affect vehicle emissions and many other vehicle functions and operations as well. Any detected problems will be recorded by OBD II and will cause the vehicle's "check engine" light to be illuminated.