Must I use a CARB credentialed tester?

Yes. Only testers credentialed under CARB’s Clean Truck Check program may perform compliance inspections and submit results to CTC-VIS. General diesel shops without credentialing cannot satisfy the requirement.

What documents should I bring to a test?

Bring vehicle registration, proof of CTC-VIS enrollment, and any prior test reports if retesting after a failure. Testers may also need access to the cab for OBD connections and visibility of emissions-related dash lamps.

Is paying the state fee enough to stay compliant?

No. Paying the annual state compliance fee registers your obligation, but you must also pass the required emissions test within your due window. Fee payment alone does not create a compliant status in CTC-VIS.

Clean Truck Check requirements

Staying compliant means more than passing a smoke test once a year. CARB expects registered vehicles in CTC-VIS, paid state fees, completed emissions inspections by credentialed testers, and timely retests after failures—all documented in the official system.

CTC-VIS registration & state fees

Every in-scope vehicle must be enrolled in the Clean Truck Check Vehicle Inspection System. Owners create an account, add VINs, and pay applicable CARB compliance fees. A commonly referenced annual state fee is $32.13 per vehicle, but fee amounts and payment rules are set by CARB and can change—verify the current schedule on arb.ca.gov before budgeting.

Registration ties each unit to a testing schedule. CTC-VIS displays due windows, compliance status, and historical test results. Fleet managers often export or mirror this data in internal maintenance systems so dispatch is never surprised by a registration hold.

Need help with first-time setup? See the CTC-VIS registration walkthrough.

Testing requirements by engine type

CARB assigns a test method based on model year and engine configuration. Most 2007 and newer heavy-duty diesel engines use OBD testing, where the tester connects to the onboard diagnostics port and verifies that emissions monitors are ready and no critical fault codes are present.

Older engines typically require smoke opacity testing, measuring visible exhaust smoke against CARB limits. Pre-test maintenance—cleaning filters, addressing blow-by, fixing turbo issues— materially affects pass rates on opacity inspections.

Test procedures and equipment standards are defined in CARB regulations. Testers must use approved equipment and follow protocols that CARB audits through its credentialing program.

Operational requirements for fleets

Beyond the test itself, fleets benefit from internal policies: monitor CTC-VIS weekly, block dispatch on non-compliant units, and route failing trucks to shop bays before due dates expire. Document who owns compliance (safety manager, maintenance lead, owner-operator) so nothing falls through during turnover.

Use our compliance checklist as a starting template, then book testing through credentialed testers on Zurfex. Review deadlines and penalties to understand what happens when requirements slip.