Washington, D.C. – The U.S. Environmental Protection Agency (EPA) has issued a final rule that will require Onboard Diagnostic Systems (OBD) on heavy-duty engines used in vehicles weighing over 14,000 lbs. The requirement, which will apply to vehicles from model year 2010 forward, will monitor the emissions control systems for malfunctions.
The requirement stems from a waiver granted in September 2008 to California, which allowed the state to implement and establish an OBD requirement that differed from federal requirements. The EPA stated that it believes a consistent nationwide program is desirable, and has worked closely with California, with the result that the new federal ruling is consistent with the California requirement in almost all important aspects.
The OBD systems are similar to those that have been required on passenger cars since the mid-1990s. The EPA is also exploring possible future regulations that would require OBD systems on heavy-duty diesel engines in non-road equipment, such as vehicles in construction, industrial and agricultural use.
The rule requires vehicle manufacturers to install OBD systems that monitor the emission control components and alert the vehicle operator to any detected need for an emission-related repair. In addition, when a malfunction occurs, the diagnostic information must be stored in the engine’s computer to assist in diagnosis and repair of the malfunction. The manufacturers are also required to make information available to the service and repair industry that will allow it to perform repair and maintenance service on the OBD systems. The EPA estimates that the requirements will add an additional increased hardware cost of approximately US$60 per diesel engine and US$70 per gasoline engine on vehicles over 14,000 lbs.
The requirement is part of the Clean Diesel Trucks and Buses program, established by the EPA in January 2001, which regulates the heavy-duty vehicle and its fuel as a single system. As part of the program, new emissions standards for heavy-duty highway engines and vehicles began to take effect in model-year 2007 and are being phased in through 2010.