Common Questions (Quick Answers)
What is a Clean Truck Check?
Clean Truck Check is California’s heavy-duty vehicle inspection and maintenance compliance program. Vehicle owners use CTC-VIS to manage reporting, fees, due dates, and test results.
How often do I need to test my vehicle?
For most vehicles, periodic emissions testing is twice per year, and due dates are shown in your CTC-VIS account.
CARB also notes that beginning October 2027, many OBD-equipped vehicles will move to four times per year testing (with certain exceptions like agricultural vehicles/motorhomes remaining annual).
What happens if my truck fails the test?
In plain terms: a “fail” means something in the emissions control system or test submission doesn’t meet requirements, so repairs and a retest may be needed. CARB advises allowing enough time in case repairs are required, especially when a vehicle is flagged as a potential high-emitter and receives a Notice to Submit Testing (NST).
What if I got an NST letter?
NST letters are issued when roadside monitoring identifies a potential high-emitter. CARB states you typically have 30 days to submit a passing emissions test, and failing to do so can lead to loss of compliance certification and a DMV registration hold.
Where do I see my due dates?
In your CTC-VIS account (CARB says to always refer to CTC-VIS for due dates).
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For more detailed answers (or fleet scheduling), email us and include: truck count + yard location + preferred time windows.
Clean Truck Valley provides mobile Clean Truck Check testing services. Official program requirements and enforcement are governed by CARB. Always refer to your CTC-VIS account for due dates.
(“Refer to CTC-VIS for due dates” matches CARB guidance.)