United States Air and Radiation EPA420-F-98-045 Environmental Protection November 1998 Agency Office of Mobile Sources v>EPA Regulatory Announcement Modification of Federal On-board Diagnostic (OBD) Regulations The Environmental Protection Agency (EPA) is issuing a final rulemaking to harmonize certain aspects of the federal On-Board Diagnostic (OBD) program with California OBDII regulations which, in general, are more stringent. This final rulemaking also allows for additional lead time for alternate fuel vehicle manufacturers to implement federal OBD on such vehicles. Background On February 19, 1993, the EPA published a final rule requiring manufac- turers of light-duty vehicles (LDVs) and light-duty trucks (LDTs) to install OBD systems beginning with the 1994 model year. OBD systems monitor emission control components for any malfunction or deteriora- tion that cause emission limits to be exceeded. OBD systems alert the driver of the need for repair via a dashboard light when the diagnostic system has detected a problem. The rulemaking also requires that, when a malfunction occurs, diagnostic information be stored in the vehicle's computer to assist the technician in diagnosis and repair. On May 28, 1997, EPA published a Notice of Proposed Rulemaking that proposed changes to the federal OBD requirements starting with the 1999 model year. I Printed on Recycled Paper ------- of EPA is finalizing modifications to the federal OBD regulations, including: « Harmonizing the emission levels above which a component or system is consid- ered malfunctioning (i.e., the malfunc- tion thresholds) with California's OBD II requirements. • Mandating that EPA OBD systems fully evaluate the entire emission control system, including the evaporative emis- sion control system. « Indefinitely extending the allowance of deficiencies for federal OBD vehicles. Indefinitely extending the allowance of optional compliance with the California OBD II requirements for federal OBD certification while also updating the allowed version of those California OBD II regulations to the most recently published version. Providing flexibility to alternate fueled vehicles through the 2004 model year. Benefits OBD systems provide substantial ozone benefits by notifying the driver of a prob- lem before the vehicle's emissions have increased significantly. If the vehicle is taken to a repair shop in a timely fashion, it can be properly repaired before any signifi- cant emission increase occurs. OBD sys- tems also provide automobile manufactur- ers with valuable feedback from their customers' vehicles that can be used to improve vehicle and emission control system designs. This final rule will not change the environmental benefits of the OBD program. for This rule provides flexibility to industry by allowing automobile manufacturers to design and implement one OBD system that will meet the requirements of both federal OBD regulations and California OBD II regulations. Additionally, one of the modifications finalized by this rule will reduce the burden on alternate fuel vehicle manufacturers by extending the lead-time they will have to comply with this regula- tion. For Additional documents on OBD are avail- able electronically from the EPA Internet server at: www.epa.gov/oms/ld-hwy.htm For further information on this final rule, please contact Holly Pugliese at: U.S. Environmental Protection Agency Office of Mobile Sources 2000 Traverwood Drive Ann Arbor, MI 48105 (734)214-4288 pugliese.holly@epa.gov ------- |