Hear from Our Customers
You already know the stakes. Operating a non-compliant truck in California means risking fines between $1,000 and $75,000 per day. That’s not a typo—per day, per vehicle.
But the financial hit isn’t the only problem. When your truck isn’t compliant, the DMV puts a registration hold on it. That means your truck sits. Your routes get delayed. Your customers start looking elsewhere. Your reputation takes a hit you didn’t earn.
CARB compliance testing keeps your registration active, your trucks moving, and your business running without interruption. You get the documentation you need for roadside inspections, and you stay off CARB’s enforcement radar. The testing itself takes less time than dealing with one violation, and the cost is a fraction of what you’d pay in fines or lost contracts.
This isn’t about checking a box. It’s about protecting your ability to operate in the busiest freight corridor in the state.
We focus exclusively on CARB compliance for heavy-duty trucks—specifically 2013 and newer models with a GVWR over 14,000 pounds. We don’t try to be everything to everyone. We do one thing, and we do it right.
Our testing is performed by CARB credentialed testers using certified OBD testing equipment. We’re located in Diamond Bar, which puts us right in the middle of one of the heaviest trucking zones in Los Angeles County. That’s not by accident.
You’re not walking into a shop that treats your semi like a side project. You’re working with people who understand the regulations, the testing requirements, and what’s actually at stake when you pull in.
First, we confirm your truck qualifies. This service applies only to trucks that are model year 2013 or newer and have a GVWR over 14,000 pounds. If your truck doesn’t meet both of those criteria, this isn’t the test you need.
Once we verify eligibility, we connect to your truck’s onboard diagnostics system. For 2013 and newer trucks, CARB requires an OBD data scan—not a tailpipe test. We’re pulling data directly from your truck’s computer to check emissions performance and system readiness.
The test itself doesn’t take long. What matters is that it’s done correctly, using CARB-certified equipment, by a credentialed tester. After the test, you get your inspection form and OBD printout for your records.
Results are transmitted to the CARB portal, and they typically show up within one to three business days. Once you’re in the system as compliant, the DMV gets updated automatically. That’s how the registration hold gets lifted—or avoided entirely if you’re staying ahead of your testing schedule.
Right now, you need testing every six months. Starting in October 2027, OBD-equipped vehicles will need it four times a year. Staying on schedule isn’t just smart—it’s required.
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You’re paying for certified OBD testing performed by a CARB credentialed tester. That’s not negotiable—it’s a state requirement. The testing equipment we use is certified by CARB. The process follows their exact protocol. And the results get transmitted directly into the state system.
You also get documentation. That includes your inspection form and the OBD test printout. Keep those in your truck. If you get pulled over at a roadside inspection, that’s your proof of compliance.
Diamond Bar sits at a major intersection of freight routes coming out of the Inland Empire and moving through Los Angeles County. CARB knows this. Enforcement is active here. Remote emission monitoring devices with automated license plate readers are scanning trucks on the road, flagging high emitters for mandatory follow-up testing.
If your truck gets flagged, you don’t get to choose when or where you test. You’re required to comply within a set timeframe, and the penalties for ignoring it are severe. Staying current with your semi-annual testing keeps you out of that situation entirely.
This is also about your business reputation. Customers and brokers are increasingly asking for proof of compliance. If you can’t show it, you’re not getting the contract. Operating a California CARB compliant fleet isn’t just legal protection—it’s a competitive advantage.
Yes. If your truck operates in California and meets the criteria—model year 2013 or newer with a GVWR over 14,000 pounds—you’re required to comply with CARB emissions testing, regardless of where it’s registered.
Out-of-state trucks aren’t exempt. CARB enforcement applies to any heavy-duty vehicle operating on California roads. That includes trucks passing through, trucks based elsewhere but running California routes, and trucks that only occasionally enter the state.
The testing frequency is the same: every six months right now, increasing to quarterly in October 2027 for OBD-equipped vehicles. If you’re caught operating in California without current compliance, the penalties are identical to what in-state operators face—up to $75,000 per day, per vehicle. The DMV can also place a registration hold, which affects your ability to renew in your home state if California flags your VIN.
Professional OBD testing for CARB compliance starts at $94. The test itself doesn’t take long—usually under an hour depending on the truck and how quickly the OBD system responds.
What you’re paying for is certified testing performed by a CARB credentialed tester using state-approved equipment. That’s not optional. CARB won’t accept results from non-certified testers or equipment, so trying to save money by going somewhere cheaper that isn’t properly credentialed will cost you more in the long run.
Some testing centers charge up to $300 for in-person testing, especially if your truck requires follow-up or retest. Our pricing is competitive and transparent. You’re not getting upsold on services you don’t need. You’re getting the test done right the first time so your results get accepted by CARB and your truck stays compliant.
If your truck fails, you’ll need to address whatever issue caused the failure before you can retest and achieve compliance. Common failure reasons include OBD system malfunctions, emission control system problems, or readiness monitor issues.
The test results will show you exactly what failed. From there, you’ll need to get the necessary repairs done. This might involve fixing a sensor, addressing an emissions control component, or resolving a check engine light that’s tied to emissions performance.
Once repairs are complete, you come back for a retest. You can’t skip this step. CARB won’t mark you compliant until you pass, and the DMV won’t lift a registration hold until your VIN shows up in the CARB system as current. The longer you wait, the closer you get to penalties and enforcement action. If you’re already operating under a violation notice, delays can trigger daily fines that add up fast.
Right now, if your truck is model year 2013 or newer with a GVWR over 14,000 pounds, you need testing every six months. That’s the current requirement as of 2025.
Starting in October 2027, the frequency increases to four times per year for OBD-equipped vehicles. That means quarterly testing. Mark your calendar now, because missing a test window puts you out of compliance immediately.
You also need to pay an annual compliance fee—$32.13 for 2026. That fee is separate from the testing cost, and it’s required whether or not you’ve been tested recently. If you miss the fee or the testing deadline, the DMV will place a registration hold on your truck. That hold stays in place until you’re current, and you can’t renew your registration until it’s lifted. Don’t wait until your registration is about to expire. Get tested early, stay ahead of the deadlines, and avoid the scramble.
You can get tested at any facility that employs CARB credentialed testers and uses certified OBD testing equipment. Not every smog check station qualifies. This isn’t the same as a standard passenger vehicle smog test.
Heavy-duty vehicle compliance testing requires specialized equipment and certification. The tester performing your OBD scan must hold a current CARB credential. The testing device must be CARB-certified. If either of those requirements isn’t met, your test results won’t be accepted, and you’ll have wasted your time and money.
We’re set up specifically for this type of testing in Diamond Bar. We’re not a general smog shop trying to handle heavy-duty trucks on the side. We focus on 2013 and newer trucks with GVWR over 14,000 pounds because that’s what the regulations require and that’s what we’re certified to do. You’re not going to show up and find out we can’t help you.
Bring your vehicle registration and any previous CARB compliance documentation if you have it. We’ll need to verify your truck’s VIN, model year, and GVWR to confirm eligibility for testing.
If this is your first time getting tested, don’t worry—we’ll walk you through what’s required. If you’ve been tested before, having your last inspection form or OBD printout can be helpful, but it’s not mandatory.
After your test, you’ll receive an inspection form and an OBD test printout. Keep both of those documents in your truck. If you get stopped at a roadside inspection or checkpoint, that’s your proof of compliance. CARB enforcement officers and CHP can request it, and not having it available can lead to delays or additional scrutiny. Store it somewhere accessible—glove box, behind the visor, or in your logbook. You don’t want to be digging through paperwork on the side of the freeway.
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