Control of Air Pollution From New Motor Vehicles and New Motor Vehicle Engines; Modification of Federal On-Board Diagnostic Regulations for: Light-Duty Vehicles, Light-Duty Trucks, Medium Duty Passenger Vehicles, Complete Heavy Duty Vehicles and Engines Intended for Use in Heavy Duty Vehicles Weighing 14,000 Pounds GVWR or Less; Extension of Acceptance of California OBD II Requirements

EPA is taking direct final action to amend and revise certain requirements associated with the Federal on-board diagnostic (OBD) system regulations. EPA previously promulgated an OBD rulemaking on December 22, 1998 (63 FR 70681) which indefinitely extended the provision allowing compliance with California OBD II requirements to satisfy federal OBD requirements. The California Air Resources Board (CARB) has recently revised their OBD II requirements and, accordingly, today's rulemaking promulgates appropriate revisions to Federal OBD regulations including: an update to the acceptable version of the California OBD II regulations that allows compliance with California OBD II regulations to satisfy Federal OBD regulations; inclusion of relevant sections pertaining to California OBD II catalyst monitoring requirements when accepting manufacturers' demonstration of compliance with California OBD II; an update of the incorporation by reference of standardized practices developed by the Society of Automotive Engineers (SAE) and the International Organization for Standardization (ISO) to incorporate recently published versions, while also incorporating by reference a new standardized protocol developed by the International Organization for Standardization (ISO) and establishing a future date by which this protocol will be the only acceptable protocol; and a technical amendment to the optional chassis certification requirements for heavy- duty (HD) vehicles weighing 14,000 pounds GVWR or less. OBD systems in general provide substantial benefits to the environment by diagnosing and alerting operators, vehicle inspection and maintenance (I/M) personnel, and service providers of deterioration or malfunction of emission related control systems.