If you have any concerns about your vehicles ability to pass a smog inspection, please let us know. We’ll be happy to answer any questions!

909-890-9806

Mechanic inspecting car engine in garage

Which vehicles require a smog check?
Most vehicles that are gasoline-powered, hybrid, or alternative-fuel vehicles over 8 model years old, and diesel vehicles model year 1998 or newer with a gross vehicle weight rating under 14,000 pounds, need a smog check.

Department of Motor Vehicles vehicle registration renewal notice form with details about the renewal process, fees, SMOG certification requirement, late payment fees, and planned nonoperation instructions. Includes contact information and a section for returning by mail.

What should I bring to a smog check appointment?
Bring your vehicle’s registration card or DMV renewal notice specifying the need for a smog check.

Mechanic using a laptop to diagnose a car engine in a garage.

Do I need a smog check if I recently moved to California?
Yes, a smog check is required when registering an out-of-state vehicle in California.

Mechanic in blue overalls using diagnostic tool on car engine in garage.

How often do I need to get a smog check?
Typically every two years (biennially) for vehicles registered in counties that require smog inspections.

Hand holding a disconnected rubber hose in a car engine bay, near electrical components and wiring.

What happens during a visual inspection?
The technician checks for tampered, missing, disconnected or modified emissions control components.

Storefront of an auto smog check service displaying signs for "Auto Smog Check Star Certified Test Only" and information about smog checks, renewals, and DMV services. The building has a tiled roof and parking spaces in front.

What is the difference between a "Test Only" station and a "Test and Repair" station?
A "Test Only" station performs smog tests but does not offer repair services, while a "Test and Repair" station does both.

Person wearing blue gloves working on a car battery

How can readiness monitors become erased or reset? Readiness monitors can be erased or reset when the vehicle's battery is disconnected, when diagnostic trouble codes are cleared, or after certain repairs, especially those related to the emissions system. This reset can cause the monitors to show as "not ready" during the Smog Check.

Calendar-style icon with "Today 90 Days" text

How long is a smog certificate valid?
A smog certificate is valid for 90 days from the date of issuance.

Hands exchanging a car key fob and several US hundred-dollar bills in front of a white car.

Can I retire my vehicle if it fails?
Yes, CAP allows qualifying vehicle owners to retire their car for a monetary incentive if it fails the smog check.

What happens if my car’s "Check Engine" light is on during the smog check?
If the "Check Engine" light is on, the vehicle will automatically fail the smog test, even if the emissions levels are within the acceptable range.

Illustration of five yellow check engine symbols on a black background: one with no text, one with a lightning bolt and the word 'CHECK,' one with 'CHECK ENGINE,' one with 'SERVICE ENGINE SOON,' and one with 'CHECK.'

Woman in white shirt thinking beside text "Failed Smog Check?" on yellow background.

What happens if my vehicle fails the smog check? If your vehicle fails, you’ll receive a Vehicle Inspection Report (VIR) detailing why it failed. Repairs must be made before a retest.

Bureau of Automotive Repair Consumer Assistance Program advertisement offering repair assistance up to $1,200 and vehicle retirement up to $1,500. Learn more or apply at www.bar.ca.gov/cap.

Is there financial assistance available for repairs? Yes, California offers programs like the Consumer Assistance Program (CAP) to help with repair costs or retiring the vehicle.

What is a STAR-certified station?
STAR stations are smog check facilities that meet higher performance standards set by the California Bureau of Automotive Repair (BAR).

An OBDII scanner screen showing readiness monitors with green check marks and labeled sections like IGN and CAT. The surrounding graphic includes the text 'Readiness Monitors' in bold white and red lettering.

What are readiness monitors, and why are they important for the Smog Check? Readiness monitors are self-tests performed by your vehicle's On-Board Diagnostic (OBD) system to verify that emission control components are functioning correctly. These monitors must be set to "ready" status for your vehicle to pass the Smog Check.

Person removing a gas cap from a car's fuel tank opening.

What is a “functional check”?
A functional check ensures components like the ignition timing, fuel cap, and check engine light are operating correctly.

Can a smog check be done if my vehicle has a modified exhaust system?
If your vehicle has a modified exhaust system that does not meet California emissions standards, it may fail the smog check. Modifications must be CARB-compliant to pass.

Car engine with red Honda VTEC valve cover under an open hood.

What does it mean if my vehicle gets a "Gross Polluter" label?
A "Gross Polluter" vehicle exceeds emission standards significantly. It must be repaired and pass a follow-up smog test at a STAR-certified station.

Car emitting white smoke from exhaust pipe