This article was submitted for publication by the California Air Resources Board

Clean Truck Check helps ensure that vehicles’ emissions control systems are properly functioning when operating in California to attain and maintain health-based air quality standards. The program applies to nearly all non-gasoline powered heavy-duty vehicles with a gross vehicle weight rating over 14,000 lbs. that operate on California public roads and highways, including government-owned vehicles. 

What are the Compliance Requirements for Clean Truck Check?

Vehicle owners need to take three steps to comply with Clean Truck Check: report, pay the annual compliance fee, and submit passing emissions compliance tests by the applicable deadline for each vehicle.

Step 1: Report
Create an account in the Clean Truck Check Vehicle Inspection System (CTC-VIS). 

Once an account is created, users report vehicle owner information or company information (such as entity name, company contact information, and USDOT number) and vehicle information. Vehicles should be added or removed from CTC-VIS within 30 calendar days of a transaction to purchase or sell a vehicle. 

Step 2: Pay annual compliance fee 

Annual compliance fee deadlines for each vehicle can be found in CTC-VIS. Fees may be paid with  credit card, debit card, and e-check. Payments made through any other CARB portals or paper checks will not be accepted. After the payment has been processed, a vehicle compliance certificate may be generated from your CTC-VIS account if the vehicle has met the testing requirement. CARB recommends you download and print a copy of the certificate for your records. 

Step 3: Submit a passing emissions compliance test

Vehicle owners must test the vehicle and submit a passing emissions compliance test. Most vehicles will have semi-annual requirements and will need to submit a passing emissions test twice a year. For vehicles registered with California DMV, emissions compliance testing deadlines are based on the vehicle’s registration expiration date (Table I). For vehicles operating in California but not registered with the California DMV or vehicles with DMV-exempt plates such as government vehicles, the testing deadline is based on the last digit of the VIN (Table II).

Bolded months indicate the month the compliance fee will be due.

Bolded months indicate the month the compliance fee will be due.

Emissions compliance tests may be submitted up to 90 days prior to the testing deadline to allow time for any necessary repairs. CTC-VIS sends out a monthly reminder email notification for vehicles with a test deadline in the next 90 days. Nearly all vehicles (including government vehicles with exempt plates) are subject to testing twice per year. 

What are my options for testing?
Fleet/vehicle owners have several options for completing emissions compliance testing. They may hire a credentialed tester or become a credentialed tester at no cost. Diesel non-OBD equipped vehicles (2012 and older diesel engines) are required to complete a smoke opacity test and a visual inspection of the vehicle’s emissions control equipment. Alternative fuel non-OBD equipped vehicles (2017 and older alternative fuel engines) are only required to complete the visual inspection. OBD equipped vehicles (2013 and newer diesel engines and 2018 and newer alternative fuel engines) are required to undergo OBD testing using a California Air Resources Board (CARB) certified OBD testing device. These devices may be non-continuously or continuously connected.

What are Clean Truck Check Telematics Devices?

Continuously connected – also known as telematics - devices are remote OBD devices, which may be hard-wired into the vehicle wire harness or plugged into the vehicle. They function automatically without human interaction to perform emissions compliance tests and submit results securely to CARB. These devices collect information such as OBD data, mileage, and engine operation status to help verify that a vehicle’s emissions control system is functioning properly while in use.

The Benefit of Clean Truck Check Telematics Devices

Continuously connected telematics devices provide a faster and more efficient way to complete emissions compliance testing and meet Clean Truck Check requirements for OBD-equipped vehicles. Since emissions compliance testing automatically occurs in the background during normal vehicle operation without the need for human intervention, owners can avoid downtime as it is no longer necessary to remove vehicles from service to perform testing.  This automated and streamlined approach reduces the administrative and operational time it takes fleets to complete emissions compliance testing.  

To learn more about the different continuously connected telematics devices that are CARB-certified please see CARB’s list of certified OBD testing devices.

For assistance with Clean Truck Check requirements, please email questions along with the applicable VIN to hdim@arb.ca.gov (include applicable VIN when emailing). Visit the Clean Truck Check page for more information on that program and CARB’s TruckStop for information on other CARB regulations.