OBD-II Systems

On Board Diagnostics II - Passenger Cars, Light-Duty Trucks, and Medium-Duty Vehicles and Engines certified under title 13, CCR section 1968.2 

California OBD-II applies to all California and "CAA Sec. 177 States" for gasoline engine vehicles up to 14, 000 lbs. Gross Vehicle Weight Rating (GVWR) starting in the 1996 MY and all diesel engine vehicles up to 14, 000 lbs. GVWR starting in the 1997 MY. Starting in the 2004 MY, Federal vehicle over 8, 500 lbs. are required to phase in OBD-II. Starting in 2004 MY, gasoline-fueled Medium Duty Passenger Vehicles (MDPVs) are required to have OBD-II. By the 2006 MY, all Federal vehicles from 8, 500 to 14, 000 lbs. GVWR will have been phased into OBD-II.

"CAA Sec. 177 States" or "California States" are states that have adopted and placed into effect the California Air Resources Board (CARB) regulations for a vehicle class or classes in accordance with Section 177 of the Clean Air Act. At this time, "CAA Sec. 177 States" are Massachusetts, New York, Vermont and Maine for 2004, Rhode Island, Connecticut, Pennsylvania for 2008, New Jersey, Washington, Oregon for 2009, Maryland for 2011, Delaware for 2014 and New Mexico for 2016. These States receive California-certified vehicles for passenger cars and light trucks, and medium-duty vehicles, up to 14, 000 lbs. GVWR."

Federal OBD applies to all gasoline engine vehicles up to 8, 500 lbs. GVWR starting in the 1996 MY and all diesel engine vehicles up to 8, 500 lbs. GVWR starting in the 1997 MY. US Federal only OBD-certified vehicles through the 2016 MY may use the US Federal allowance to certify to California OBD II but then turn off/disable 0.020" evap leak detection). Starting on the 2017 MY, Federal vehicles must comply with EPA Tier 3 standards that include LD and HD standards for exhaust emissions (NMOG, NOx and PM) evaporative emission standards, reduction of sulphur in fuel, E10 test fuel and alignment of OBD requirements with CARB OBD-II regulations. For the 2017 MY EPA is referencing CARB OBD-II regulations thereby mandating 0.020" evap system leak detection requirements for all 50 states.

Starting in the 2004 MY, Federal vehicle over 8, 500 lbs. are required to phase in OBD-II. Starting in 2004 MY, gasoline-fueled Medium Duty Passenger Vehicles (MDPVs) are required to have OBD-II. By the 2006 MY, all Federal vehicles from 8, 500 to 14, 000 lbs. GVWR will have been phased into OBD-II.

OBD-II system implementation and operation is described in the remainder of this document.