CARB Clean Truck Check Failed? Here's Exactly What to Do Next

A failed CARB Clean Truck Check carries no fine by itself, but your DMV registration hold stays active until you repair the issue and pass a retest. The fastest path back to compliant is to diagnose the exact failure, fix the root cause, and retest, ideally on-site so you do not lose more road time.

Fast facts

• The failure itself carries no penalty. The cost is the DMV registration hold until you pass a retest.
• OBD failures usually mean active fault codes, incomplete readiness monitors, or a faulty EGR, DPF, or catalyst.
• OVI failures usually mean excessive smoke opacity, missing or damaged emissions components, or visible fuel leaks.
• OBD retests upload immediately; OVI retests take several business days to process.

Step 1: Understand why you failed

Get a detailed explanation of the failure reason. OBD test failures typically involve active fault codes in the emissions system, incomplete readiness monitors, or malfunctioning components like the EGR system, DPF, or catalyst. OVI failures commonly stem from excessive smoke opacity, missing or damaged emissions control components, or visible fuel leaks.

Step 2: Get the vehicle to a qualified repair shop

Take your vehicle to a repair facility that specializes in heavy-duty diesel emissions systems and knows CARB Clean Truck Check requirements. For OBD-related failures, ask the shop to diagnose the root cause, clear codes after repair, and complete a drive cycle to establish readiness monitors before retesting.

Step 3: Schedule a retest

After repairs are finished, schedule a retest. Mobile testing lets you retest at your location instead of driving the rig back to a station. For OBD retests, confirm all readiness monitors are complete before testing to avoid another failure. We retest across Sacramento, the Sacramento Region, and the SF Bay Area.

Step 4: Confirm compliance status

After you pass, verify your compliance status in the CARB Clean Truck Check portal. OBD status updates immediately upon upload, while OVI results require several business days for CARB processing. Once CARB confirms compliance, your DMV hold clears.

Can you get a waiver or extension?

CARB may grant hardship extensions or repair waivers for operators who demonstrate good-faith repair efforts while facing unusually high costs. Contact CARB directly if your situation may qualify.

Need a retest after repairs? Call us at (916) 538-7777.