FAQ – Clean Truck Check – HD I/M Program

Clean Truck Check – FAQ:

Q: What does the Clean Truck Check test consist of?

A: Testing for the Clean Truck Check program means you will need to have one of two tests in order to determine compliance.

• If your vehicle is OBD equipped (2013 and newer), we will perform the HD I/M test, and the results will be sent to CARB electronically.

• If your vehicle is older than 2013, we will perform a functional inspection and PSIP test (often referred to as an opacity test) to determine if you are compliant. To perform the test, we will need access to the engine data plate, exhaust system, and throttle.

Q: What else do I need to do?

A: In addition to having the physical vehicle testing done, you will need to use the online CARB portal in order to pay the annual fee. https://cleantruckcheck.arb.ca.gov/

Q: Does Diesel Emissions Service offer Clean Truck Check – HD I/M testing?

A: Yes. We have locations in Redding, CA, Sacramento, CA and now Portland, OR, for those heading to CA.  Each DES location has CARB-certified staff and equipment to perform the testing.

Q: Who has to participate in the CTC – VIS program?

A: Essentially, all diesel/hybrid vehicles with a GVWR (gross vehicle weight rating) over 14,000lbs will be required to stay compliant with the Clean Truck Check program. You can typically find the GVWR of your vehicle on the driver’s side door jamb label. Even non-commercial vehicles such as RVs are subject to this program if the vehicle is registered in CA.

Q: Which vehicles are NOT subject to the regulation?

A: The heavy-duty vehicle types shown below are exempt from the regulation:

• Zero-emission vehicles

• Military tactical vehicles (title 13, CCR, section 1905)

• Emergency vehicles (California Vehicle Code section 165 or California Health and Safety Code section 1797.84)

• Historical vehicles (authorized by California Vehicle Code section 5004)

• New vehicles with engines certified to the most stringent optional, NOx standard (less than or equal to 0.01 g/bhp-hr) -Only during the first four years of Clean Truck Check implementation (2023-2027)

• Motorhomes registered outside of California

• Vehicles operating under an experimental permit (authorized by California Health and Safety Code section 43014)

Q: What is my deadline for testing?

A: Starting January 2025, CA-registered vehicles will have a deadline based on the vehicle registration date. The deadline for out-of-state vehicles will be based on the last digit of the VIN. See Table II in the link below (https://ww2.arb.ca.gov/resources/documents/agricultural-vehicles-california-motor-homes-annual-compliance-requirements)

Important Milestones Diagram

NEXT STEPS

Clean Truck Check is now in full effect. To ensure your truck meets California’s emissions standards, it may be randomly selected for roadside testing using emissions monitoring devices. If your truck is flagged for potential high emissions, you’ll receive a Notice to Submit to Testing.

What to Do:

1. Schedule a Test: You have 30 days to get your truck tested at a certified emissions testing facility.

2. Make Repairs: If necessary, address any issues to ensure your truck passes the test.

3. Avoid Penalties: Failure to comply with the Notice to Submit to Testing or emissions standards may result in additional testing and penalties.

2026 Clean Truck Check Compliance Updates

Compliance Deadlines: Deadlines are no longer a single fixed window. They are now determined by:

• CA Registered Vehicles: Your deadline is the month your DMV registration expires.

• Out-of-State / Exempt Vehicles: Your deadline is based on the last digit of your VIN (e.g., VIN ending in ‘1’ is due in February).

To demonstrate compliance, owners must:

Submit a Passing Emissions Test:

• This is a new requirement since 2024. You must pass a periodic emissions test (likely semi-annual) no more than 90 days before your compliance deadline. Testing must be performed by a CARB-credentialed tester.

Pay the 2026 Annual Compliance Fee:

• The fee for 2026 is $32.13 per vehicle (effective Jan 1, 2026). This must be paid through the CTC-VIS portal by your compliance deadline.

Clear Outstanding Violations:

• Any unresolved enforcement violations or blocks must be cleared before your deadline to receive your certificate.

Failure to comply may result in DMV registration holds, penalties, or restrictions on vehicle use. Be proactive!

Stay in the Loop

Keep up-to-date on Clean Truck Check regulations and requirements to avoid penalties and even DMV registration stops.

• Detailed Information: Learn more about Clean Truck Check by visiting: Clean Truck Check

• Stay Updated: Subscribe to receive automatic email updates on Clean Truck Check implementation and other activities.

• Contact CARB: If you have additional questions, contact staff at mhdim@arb.ca.gov. CARB also has a hotline (1-866-634-3735) that provides compliance assistance for multiple CARB regulations.

LINKS:

CARB Clean Truck Check Links:

• https://ww2.arb.ca.gov/overview-fact-sheet-clean-truck-check

• https://ww2.arb.ca.gov/our-work/programs/truckstop-resources/truckstop/regulations/clean-truck-check-hd-im

• https://ww2.arb.ca.gov/resources/documents/agricultural-vehicles-california-motor-homes-annual-compliance-requirements

More links:

• Motor home Fact Sheet – Clean Truck Check

  • For motorhomes subject to annual testing requirements, see this page.

  • For motorhomes subject to semi-annual testing requirements, see this page.

• Dealer Fact Sheet – Clean Truck Check

• Vehicles Not Subject to Clean Truck Check

• Agricultural Vehicles Requirements Clean Truck Check | California Air Resources Board

Diesel Emissions Services (DES) has the expertise, diesel technicians, and facilities to service your aftertreatment systems successfully.

Most of our locations feature a complete DPF Cleaning facility, aftertreatment diagnostic/testing, and a full inventory of aftertreatment parts for quick servicing of your emissions system.