Heavy Duty (HD) OBD II Systems

Starting in the 2010 model year, California and Federal gasoline fueled and diesel fueled on road heavy duty engines used in vehicles over 14, 000 lbs. GVWR are required to phase into HD OBD II. All vehicles over 14, 000 lbs. GVWR must comply for the 2013 model year. Vehicles that do not comply with HD OBD II during the phase in period must comply with EMD+.