OBD and Opacity Testing Services for Heavy-Duty Vehicles

Under California Air Resources Board (CARB) regulations, every diesel vehicle over 14,000 lbs GVWR is required to undergo CARB emissions testing periodically. However, the specific test mandated hinges upon your engine's model year. Clean Truck Solutions offers both certified OBD diagnostic scans and opacity testing services using SAE J1667 smoke opacity equipment, bringing them right to your site.

Speak to a Certified CARB Tester: (213) 334-5626

Testing Method At-a-Glance:

| Engine Model Year        | Required CARB Inspection Method                           | Test Duration       | Recommended Frequency                            |

|--------------------------|---------------------------------------------------------|--------------------|--------------------------------------------------|

| 2013 & Newer Diesel      | OBD Electronic Diagnostic Scan (Plugs into vehicle port) | ~10 to 15 mins     | Semi-Annual (2x/year) (Annual for CA RVs)      |

| 2012 & Older Diesel      | SAE J1667 Smoke Opacity + Visual Inspection              | ~20 to 30 mins     | Semi-Annual (2x/year) (Annual for CA RVs)      |

The Two Testing Methods Explained

Why the Distinction Matters: Submitting the incorrect test type to the CARB CTC-VIS state portal will lead to an automatic rejection, causing your DMV registration to be on hold and risking daily non-compliance penalties.

1. On-Board Diagnostics (OBD) Scans (2013 & Newer Engines)

If your truck or RV features a diesel engine built in 2013 or later, its internal computer continuously monitors emissions control hardware, which includes the Diesel Particulate Filter (DPF), Selective Catalytic Reduction (SCR), and Exhaust Gas Recirculation (EGR) systems.

How It Works: Our CARB-credentialed technician connects a state-validated mobile OBD device to your vehicle's diagnostic port.

What Is Checked: The device scans for active Malfunction Indicator Lights (Check Engine Light), active/pending Diagnostic Trouble Codes (DTCs), and confirms that all onboard emissions monitors are set to 'Ready.'

The Advantage: This process is fast, digital, and non-invasive. Once scanned, data is transmitted directly to the state CTC-VIS database in real time.

2. Smoke Opacity & Visual Equipment Inspection (2012 & Older Engines)

Older heavy-duty diesel vehicles do not have standardized OBD communications for state reporting. Thus, CARB mandates a physical visual inspection alongside the SAE J1667 snap-acceleration smoke opacity testing services for these vehicles.

Visual Assessment: We check your exhaust system to ensure all necessary factory emissions control equipment (EGR, converters, mufflers) is intact and unmodified.

Opacity Test: Using a specialized, calibrated optical smoke meter attached to your exhaust pipe, we measure the density of the exhaust smoke during snap accelerations.

Passing Standards: The exhaust smoke opacity must remain below CARB's stringent percentage thresholds based on the engine's manufacturing year to pass the inspection.

What Happens During a Mobile Testing Visit

Engine & VIN Verification: Under 5 minutes. Our mobile technician verifies the VIN and engine emission control label (ECL) on-site to ensure we perform the correct CARB emissions testing mandated for your engine year.

Diagnostic Scan or Opacity Run: 10 to 20 minutes. We conduct the digital OBD diagnostic scan or prepare the SAE J1667 smoke meter for physical acceleration runs. There's no need to move your truck from your yard or driveway.

CTC-VIS State Database Submission: Immediate field transmission. Passing results are uploaded directly into the official CARB Clean Truck Check database from our mobile unit.

Pre-Clearance & Fault Guidance: Diagnostic support. If an OBD scan reveals a 'Not Ready' status or the opacity test indicates high smoke density, we provide you with the fault codes or diagnostic readouts for your mechanics to address the issue before any re-testing.