California Air Resources Board

Overview

The purpose of this guidance is to provide vehicle owners subject to annual testing information on how to comply with Clean Truck Check.

Key highlights from this guidance are:

• Vehicles subject to Clean Truck Check must be reported in CTC-VIS and compliant before they may operate on California public roads and highways. Annual compliance fees for each year will be due upon the vehicle’s compliance deadline.

  • A full overview may be found here. Compliance Requirements Overview | Español | ਪੰਜਾਬੀ

• California registered motor homes (for recreational and emergency use), and vehicles that meet the requirements to be designated as agricultural vehicles, are only required to submit to emissions compliance testing once annually. 

  • Motor homes not for recreational use or emergency occupancy (e.g. commercial use motor homes) must follow these compliance requirements. Clean Truck Check Requirements for Vehicles Subject to Semi-Annual Compliance

  • What is an agricultural vehicle? See details at Agricultural Vehicles Requirements Clean Truck Check | California Air Resources Board

• California registered vehicle compliance deadlines will align with the vehicles’ DMV registration expiration date. Note that this may vary for the 2024 compliance deadline. Refer to Table I for a vehicle’s 2024 compliance deadline month.

• Vehicles registered outside of CA that operate on CA public roads and highways and CA Exempt vehicles will have compliance deadlines based on the last digit in the Vehicle Identification Number (VIN). Refer to Table II for details.

• Compliance demonstration will require the payment of the annual compliance fee and the clearance of any outstanding enforcement violations for the vehicle in question.

• Emissions compliance testing requirements are effective starting on October 1, 2024. All compliance deadlines of January 1, 2025 or later will require a passing compliance test to be submitted as part of their compliance demonstration. Vehicles may submit tests no more than 90 days prior to the vehicle’s compliance deadlines. For example, a vehicle with a compliance deadline of February 1, 2025 may submit a passing emissions test as early as November 3, 2024.

  • How must my vehicles be tested? 
    Specifics are available at Emissions Compliance Testing Requirements

    The testing requirements depend on whether your vehicle/engine is equipped with OBD or not.

    OBD-equipped vehicles (2013 and newer diesel engines and 2018 and newer alternative fuel engines) are required to undergo a scan of the engine’s OBD data using a California Air Resources Board (CARB) certified OBD testing device. 

    Diesel non-OBD 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, referred to in this program as the Vehicle Emissions Control Equipment Inspection. Alternative fuel non-OBD vehicles (2017 and older alternative fuel engines) are only required to complete the visual inspection and are not subject to the smoke opacity test requirement. 

• Non-compliance may result in DMV registration blocks and other enforcement action.

Vehicles Affected by this Guidance

Nearly all diesel and alternative fuel heavy-duty trucks, buses, and other vehicles with a gross vehicle weight rating over 14,000 pounds that operate in California are subject to the compliance deadlines mentioned above. Affected vehicles include hybrid trucks and buses, commercial vehicles, privately-owned vehicles, government vehicles, and vehicles registered outside of California that operate on CA public roads and highways. For information on vehicles that are exempt from Clean Truck Check, please refer to the Fact Sheet: Compliance Requirements Overview | Español | ਪੰਜਾਬੀ

A. California Registered Vehicles

Compliance deadlines for California registered vehicles are based on their DMV registration expiration dates.

California Motor homes (including recreational and emergency use motor homes), and vehicles that meet the requirements to be classified as agricultural vehicles, are subject to annual compliance deadlines only. 

• Motor homes not for recreational use or emergency occupancy (e.g. commercial use motor homes) must follow these compliance requirements. Clean Truck Check Requirements for Vehicles Subject to Semi-Annual Compliance

Compliance Deadlines may be found in the vehicle’s CTC-VIS account.

Table I: Compliance Deadlines for California Registered Vehicles

Vehicles are required to ensure that they have paid their annual compliance fee and have no outstanding enforcement violations as part of their compliance demonstration.
You may submit Clean Truck Check emissions tests up to 90 calendar days prior to the vehicle's compliance deadline. 

B. Non-California Registered Vehicles and DMV Exempt Plated Vehicles

Non-California registered vehicles include vehicles registered in other states and countries, as well as federal vehicles not registered in any DMV jurisdiction. DMV exempt plated vehicles include California local and state government vehicles exempt from DMV re-registration requirements.

These vehicles’ emissions compliance testing compliance deadline is based on the last number of the vehicle’s vehicle identification number (VIN). To identify when your non-California registered/exempt plated vehicles refer to Table II below.  Compliance Deadlines may be found in the vehicle’s CTC-VIS account.

Table II: Compliance Testing Deadlines for Non-California Registered and DMV Exempt Plated Vehicles

As with CA registered vehicles, non-CA registered vehicles are required to ensure that they have paid their annual compliance fee and have no outstanding enforcement violations as part of their compliance demonstration.
You may submit Clean Truck Check emissions tests up to 90 calendar days prior to the vehicle's compliance deadline. 

In the VIN-based compliance schedule, a vehicle’s emissions compliance testing deadline falls on last day of the compliance deadline month shown in Table II.