California Air Resources Board

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 can be found at Clean Truck Check - Overview Fact Sheet | 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 Clean Truck Check - Agricultural Vehicles Requirements.
• Compliance deadlines for all vehicles may be found in Tables I & II below. 
• 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 Clean Truck Check - 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. 
• Emissions compliance testing must be performed by a CARB credentialed tester and passing tests may be submitted by the tester up to 90 days prior to the vehicle’s compliance deadline to allow time for any necessary repairs.
  • For example, a vehicle with a compliance deadline of February 1, 2025 may submit a passing emissions compliance test as early as November 3, 2024. 
• 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 visit Compliance Requirements Overview | Español | ਪੰਜਾਬੀ.

A. California Registered Vehicles

Compliance deadlines for California registered vehicles are based on their DMV registration expiration dates. This applies to any vehicles historically registered with CA DMV even if they are now registered outside of California. Compliance Deadlines may be found in the vehicle’s CTC-VIS account, and these due dates are what are used to calculate your compliance status.

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.

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

The following vehicles’ compliance deadlines are based on the last number of the vehicle’s Vehicle Identification Number (VIN).

Please refer to Table II below. These vehicles will have reoccurring compliance deadlines every six months.
Compliance Deadlines may be found in the vehicle’s CTC-VIS account, and these due dates are what are used to calculate your compliance status.

• Non-California registered vehicles
  • Not including vehicles historically registered with CA DMV (see Table I)
• DMV exempt plated vehicle- state and local government vehicles
• Federal government vehicles 

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.