OBD Tests & Smoke Opacity Tests

Vehicles subject to on-board diagnostic (OBD) testing are:

• Heavy-duty (Gross Vehicle Weight Rating ≥ 14,000 lbs.) diesel vehicles and diesel hybrids with 2013 and newer model year engines.

• Alternative fuel (e.g., natural gas) and alternative fuel hybrid heavy-duty vehicles with 2018 and newer model year engines

Vehicles subject to Non-OBD testing require smoke opacity test:

• Credentialed testers must use an SAE J1667-compatible smoke meter for non-OBD vehicle emissions tests.

• A visual inspection of emissions equipment must be completed using the Vehicle Emissions Control Equipment Inspection Form.

Resources

• CARB Periodic Smoke Inspection Program (PSIP)

• Clean Truck Check (HD/IM)

• Report for Clean Truck Check

• OBD - On-Board Diagnostic Program