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Starting January 1, 2025, California requires semi-annual emissions testing for heavy-duty trucks. Miss a deadline, and you’re looking at fines up to $10,000 per vehicle per day. The DMV can place registration holds that ground your trucks immediately.
You need a passing Clean Truck Check certificate to register your vehicle, access freight facilities, and keep operating in California. Without it, your truck sits. Your revenue stops. Your customers find someone else.
We specialize in CARB emissions testing for 2013 and newer diesel trucks over 14,000 pounds GVWR in Diamond Bar, CA. We handle the OBD testing required under California’s Heavy-Duty Inspection and Maintenance program. You get your certificate, submit it to CARB, and get back to work.
We focus exclusively on 2013+ model year trucks that need Clean Truck Check compliance. We’re CARB credentialed, which means our testers passed the state’s training and exam. We use CARB-certified OBD testing devices, and we know exactly what triggers a pass or fail.
Diamond Bar sits right in the heart of Southern California’s trucking corridor. We’re positioned to serve owner-operators and fleets running the I-10, I-60, and I-605 routes. You’re not our side project. Heavy-duty compliance is what we do.
If your truck is model year 2012 or older, or under 14,000 pounds GVWR, this service doesn’t apply. CARB’s testing requirement is specific, and so are we.
You bring your 2013 or newer diesel truck to our Diamond Bar location. We connect to your truck’s OBD system using CARB-certified testing equipment. The system pulls data directly from your engine’s onboard diagnostics.
We’re checking for emissions-related fault codes, readiness monitors, and whether your truck’s emissions controls are functioning properly. If your diesel particulate filter, exhaust gas recirculation, or other emissions systems show issues, the test fails. If everything checks out, you pass.
Once you pass, you receive a Clean Truck Check certificate. You submit that certificate through CARB’s online system. You can submit a passing test up to 90 days before your compliance deadline, so you’re not scrambling at the last minute.
The test itself is quick. What takes time is fixing issues if your truck fails. That’s why operators who stay on top of maintenance have fewer surprises during testing.
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California’s Heavy-Duty Inspection and Maintenance program targets 2013 and newer diesel trucks because they’re equipped with OBD systems. These trucks represent the cleanest diesel technology, but CARB still requires regular testing to confirm emissions controls are working.
Right now, testing happens twice a year. By October 2027, that increases to four times annually. Each test costs you time and money, but skipping one costs you exponentially more. Ports, rail yards, and freight facilities in California are starting to require proof of Clean Truck Check compliance before allowing entry.
Diamond Bar’s location near major logistics hubs means many trucks passing through here are subject to these rules. If you’re an out-of-state carrier operating in California, you’re not exempt. CARB’s regulations apply to any heavy-duty truck operating on California roads, regardless of where it’s registered.
The annual compliance fee is $31.18 as of 2025. Add testing fees, and you’re still looking at a fraction of what one day of fines would cost. The math is simple: stay compliant or risk losing everything.
No. CARB’s Heavy-Duty Inspection and Maintenance program only applies to model year 2013 and newer diesel trucks with a GVWR over 14,000 pounds.
Trucks from 2012 and older don’t have the OBD systems that this testing program relies on. If your truck is older than 2013, you’re not required to get a Clean Truck Check certificate. CARB designed this program specifically around the emissions technology that became standard in 2013.
If you’re unsure whether your truck qualifies, check your vehicle’s model year and GVWR. Both criteria must be met for the testing requirement to apply.
If your truck fails, you don’t get a passing certificate. That means you can’t submit proof of compliance to CARB, and you risk registration holds and daily fines.
The test fails when your OBD system shows emissions-related fault codes or when readiness monitors aren’t set. Common culprits include malfunctioning diesel particulate filters, faulty exhaust gas recirculation systems, or issues with your selective catalytic reduction system. You’ll need to repair whatever triggered the failure, then retest.
Some operators try to clear codes right before testing, but OBD systems need time to run through drive cycles and set readiness monitors. If you show up with a freshly cleared system, it won’t pass. The best approach is maintaining your emissions equipment year-round so you’re not scrambling when deadlines hit.
As of January 2025, you need testing twice a year. By October 2027, that increases to four times per year.
CARB sets specific compliance deadlines based on your vehicle identification number. You can submit a passing test up to 90 days before your deadline, which gives you some flexibility for scheduling. Missing a deadline triggers immediate consequences: registration holds and fines that start accruing daily.
The testing frequency is increasing because CARB wants to catch emissions system failures faster. Heavy-duty trucks make up only 3% of California’s vehicles but produce over half of the state’s smog-causing pollution. The more frequent testing is designed to keep emissions controls working properly throughout the year, not just when operators remember to get tested.
No. You need a CARB credentialed tester using CARB-certified OBD testing equipment.
Not every smog shop can perform Clean Truck Check testing. CARB requires testers to complete specific training and pass an exam before they’re credentialed. The testing equipment must also meet CARB’s certification standards for heavy-duty vehicles.
We’re credentialed to perform these tests in Diamond Bar, CA. We focus specifically on 2013+ trucks over 14,000 pounds GVWR, which means we’re set up for the exact vehicles CARB’s program targets. If you go to a facility that isn’t credentialed or doesn’t have the right equipment, your test won’t count toward your compliance requirement.
Fines range from $1,000 to $10,000 per vehicle per day. In some cases, penalties can reach $75,000 per day depending on the violation.
CARB doesn’t mess around with enforcement. If you’re operating without a valid certificate, the fines start immediately and compound daily. The DMV can also place registration holds on non-compliant vehicles, which effectively grounds your truck until you come into compliance.
For owner-operators, a few days of fines can wipe out weeks of revenue. For fleets, the costs multiply fast. Beyond the financial hit, you lose access to freight facilities that require Clean Truck Check compliance. The cheapest option is always staying compliant from the start.
Yes. If your 2013 or newer diesel truck over 14,000 pounds GVWR operates on California roads, you need Clean Truck Check compliance regardless of where it’s registered.
CARB’s regulations apply to any heavy-duty vehicle operating in the state. It doesn’t matter if you’re based in Nevada, Arizona, Oregon, or anywhere else. If you’re hauling freight through California, you’re subject to the same testing requirements as California-registered trucks.
Many out-of-state carriers don’t realize this until they’re hit with fines or denied entry to a freight facility. The enforcement is real, and the penalties are the same. If you regularly run California routes, factor Clean Truck Check testing into your compliance schedule just like California operators do.
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