Expert Truck Compliance Services in California

OBD testing applies to 2013 and newer diesel trucks and buses with a Gross Vehicle Weight Rating (GVWR) over 14,000 pounds that are equipped with an OBD system.

CARB requires OBD testing twice per year (semi-annually) for vehicles subject to the Clean Truck Check program. Testing frequency may vary based on compliance deadlines or enforcement schedules.

A Clean Truck Check OBD test is an emissions inspection mandated by the California Air Resources Board (CARB) for heavy-duty diesel vehicles. It uses your truck’s On-Board Diagnostics (OBD) system to detect emission-related issues and ensure your engine and aftertreatment systems are functioning correctly.

OBD testing checks your vehicle’s electronic emissions system through a diagnostic port, while opacity testing measures visible smoke emissions from the exhaust. Older trucks (typically 2012 and earlier) without OBD systems must undergo opacity testing instead.

The OBD test typically takes 10–15 minutes per vehicle. Testing can be performed on-site at your business or fleet yard for convenience.

Yes, we offer mobile OBD testing services. Our certified tester will come to your location, perform the inspection, and upload the results directly to CARB. You'll also receive a screenshot of your test results for your records.

After your test, we upload your results to the CARB Clean Truck Check Vehicle Information System (CTC-VIS). You can verify your compliance status by logging into your CARB portal or contacting us for confirmation.

If your vehicle fails the OBD test, the report will show diagnostic trouble codes (DTCs) that identify the issue. You need to fix these problems and retest your vehicle before the compliance deadline to remain compliant.

Yes, some vehicles are exempt from OBD testing. These include gasoline, hybrid, natural gas, and low-use diesel vehicles, as well as certain specialty or off-road vehicles. However, exempt vehicles must still be reported to CARB through the Excluded Diesel Vehicle Reporting (EDVR) system.

We can help you set up your CTC-VIS portal and link your vehicles for automatic result uploads. Proper setup ensures your test results are received and that you avoid DMV registration holds for noncompliance.