Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock () or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

JavaScript appears to be disabled on this computer. Please click here to see any active alerts.

Proposed Rule for 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

The proposed rule for the 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

Proposed Rule (pdf) (134 KB, published June 17, 2003)

Proposed Rule for 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

Regulations for Emissions from Vehicles and Engines