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  • What is the Smog Check Program?
    The Smog Check Program is an important part of the State's efforts to improve the air we breathe. Smog Check inspections are designed to identify vehicles with excess emissions so they can be properly repaired. The Program has greatly reduced air pollution created by millions of cars in California.
  • Who administers the Smog Check Program?
    The California Department of Consumer Affairs' Bureau of Automotive Repair (BAR) administers the Smog Check Program. Vehicles are inspected each year by more than 7,000 State-licensed and independently owned stations throughout the State.
  • What vehicles require a Smog Check
    Gasoline-powered vehicles, hybrid vehicles, and alternative-fuel vehicles that are model year 1976 and newer require a Smog Check, with the following exceptions: Six model-years and newer do not need a biennial (every other year) inspection. Four model-years and newer do not need a change-of-ownership inspection. To determine the first year a vehicle is subject to a biennial or change-of-ownership Smog Check, add six or four, respectively, to the model year of a vehicle. For example, a 2010 model-year vehicle will first be subject to a biennial Smog Check in 2016 (2010 + 6 = 2016) and a change-of-ownership Smog Check in 2014 (2010 + 4 = 2014). Diesel-powered vehicles 1998 and newer with a gross vehicle weight rating of 14,000 pounds and less require a Smog Check. Motorcycles and electric-powered vehicles are currently exempt from the Smog Check Program.
  • Is the Smog Check Program biased against older vehicles?
    No. While California law requires the Smog Check Program to focus on high-polluting vehicles, the Smog Check Program also does not require older vehicles to meet the same emissions standards as newer vehicles. Smog Check emissions standards take into consideration the age, make and model of each vehicle, so that a vehicle is never held to a standard that applied when the vehicle was originally manufactured.
  • My 1976 model-year vehicle was built in 1975. Why isn't it exempt from Smog Check?
    The Smog Check exemption is based on the model-year of the vehicle, not the date of manufacture. Accordingly, a 1976 model-year vehicle is not exempt.
  • I have a vehicle that is six model-years old. My DMV registration renewal notice says it must have a Smog Check, but I thought it was exempt from the biennial Smog Check requirement."
    A gas-powered vehicle is excused from Smog Check until it is seven model-years old. Department of Motor Vehicles (DMV) computers are designed to recognize the exemption and process your renewal accordingly. Contact DMV if you think there is an error. If you are unable to resolve the problem with DMV, a state Referee facility may be able to help. Call the Referee Call Center at (800) 622-7733 to schedule an appointment.
  • Are government-owned vehicles subject to Smog Check?
    Yes. Federal, state, county, city, and special district agencies that own or lease passenger vehicles or light-duty trucks are subject to the Smog Check Program. The Federal Clean Air Act and California Health and Safety Code mandate that all vehicles subject to the Smog Check Program receive an inspection. These requirements include vehicles classified as emergency equipment.
  • What is an Enhanced Area?
    An Enhanced Area is an urban region designated by the U.S. Environmental Protection Agency as not being in attainment with federal health standards for ozone. Vehicles registered in an Enhanced Area are subject to a treadmill emissions test on a dynamometer and may require testing at a STAR-certified station.
  • Where does the money from the Smog Check go?
    There are approximately 7,500 privately owned and operated Smog Check stations in California. The inspection and repair fees they charge are neither set nor collected by BAR. Rather, prices are market driven. An $8.25 Smog Check certificate fee is assessed on vehicles once they pass their Smog Check. This money funds BAR, including administration of the Smog Check Program and consumer protection operations relating to automotive repair.
  • Have California vehicle emissions standards changed?
    Yes. BAR periodically adjusts some standards to increase their fairness. As a result, some standards become slightly more stringent than they were previously and some slightly more lenient. California's emissions standards consider the model-year, vehicle make and model, and gross weight of the vehicle. Older cars have less stringent standards than newer ones. No older vehicle is ever held to the same standards as a newer, more technologically advanced vehicle. Allowances are made for normal wear and tear in a vehicle's emissions control system as it ages. Standards are established through a regulatory process and are made available for public comment before they are adopted. The last adjustment occurred in 2010.
  • What is a Test-Only station?
    Test-Only stations are licensed by BAR to only perform Smog Checks. These stations are not authorized to diagnose the reasons for a Smog Check failure, or perform repairs on vehicles.
  • What is a Test-and-Repair station?
    Test-and-Repair stations are licensed by BAR to perform Smog Checks and repairs on vehicles.
  • Where can I find Smog Check stations in my area?
    To find a Smog Check station near you, click here or call (800) 952-5210.
  • What is a STAR station?
    Some vehicles require a Smog Check at a STAR station. STAR stations meet specified performance standards established by BAR. Some STAR stations are licensed to perform only tests, while others are licensed to perform both tests and repairs. The station is required to post a sign on the services it is licensed to perform.
  • How will I know if I need to take my car to a STAR station?
    Your DMV registration renewal form will indicate whether your vehicle requires a Smog Check at a STAR station.
  • How can I find a STAR station near me?
    To find a STAR station near you, click here or call (800) 952-5210.
  • Why am I being sent to a STAR station?
    State law requires that a percentage of vehicles have their Smog Checks performed at a STAR station. One reason may be that your vehicle was identified as being more likely than others to emit unhealthy levels of harmful pollutants. This may be true even though your vehicle may never have failed a Smog Check. Another possibility is that your vehicle was chosen as part of a random selection for Smog Check Program evaluation purposes.
  • How often does my vehicle have to be tested?
    Smog Checks are required biennially (every other year) on vehicles more than six model-years old. Additionally, a Smog Check is required if you sell a vehicle that is more than four model-years old and when registering an out-of-state vehicle for the first time in California.
  • How long does a Smog Check take?
    The average Smog Check takes about 20-30 minutes to complete.
  • How much does a Smog Check cost?
    BAR does not regulate inspection prices, but recommends that you shop around and compare prices of several different stations before taking your vehicle in for its Smog Check.
  • How long is a Smog Check certificate valid?
    An electronic certificate of compliance is issued and stored at DMV when a vehicle passes a Smog Check. The certificate is valid for 90 days.
  • How can I help my vehicle pass a Smog Check?
    Performing regular and proper maintenance according to your owner's manual and not tampering with the emissions-control equipment will help improve your vehicle's chances of passing a Smog Check. If the "Check Engine" light comes on, take your vehicle to a licensed repair station as soon as you can to have the problem diagnosed-do not wait for the vehicle's next scheduled Smog Check. A blinking or flashing light indicates a malfunction that should be addressed immediately to avoid serious damage to the engine or emission-control systems. Check your owner's manual for repairs that may be covered under your vehicle manufacturer's emissions warranty.
  • What is a "pre-test?""
    A pre-test or pre-inspection is an unofficial test provided as an option to vehicle owners prior to having an official Smog Check performed on the vehicle. Smog Check stations may charge for this service if authorized by the consumer.
  • What is a Directed Vehicle?
    State law requires that a percentage of vehicles have their Smog Check performed at a STAR station. One reason may be that your vehicle was identified as being more likely than others to emit unhealthy levels of harmful pollutants, even though it may never have failed a Smog Check. Another possibility is that your vehicle was chosen as part of a random selection for program evaluation purposes.
  • What is a Gross Polluter?
    A Gross Polluter is a vehicle with excess hydrocarbon, carbon monoxide or oxides of nitrogen emissions as established by DCA and ARB. Gross Polluters can only be certified at a STAR station which will confirm the vehicle was repaired and brought into compliance with required emissions standards. BAR identifies these vehicles to encourage their immediate repair.
  • What happens if my vehicle fails a Smog Check?
    Ask the inspector to explain the reason for the failure and then seek a repair technician to correct the problem. Many inspectors are also licensed to perform repairs. If you have a dispute about the results of your Smog Check, you can file a complaint online with BAR. Or, if you would like a second opinion about the inspection, schedule an appointment with a state Referee by calling (800) 622-7733 or by visiting
  • What are the elements of a Smog Check?
    Smog Checks are designed to measure the amount and type of pollutants your vehicle is emitting. A Smog Check may include any of the following tests: Visual inspection of emission control components and systems Functional inspection of the vehicle's check engine light, ignition timing, exhaust gas recirculation system, fuel evaporative system, and gas cap Functional inspection of the vehicle's On-Board Diagnostic (OBD) system Tailpipe emissions inspection
  • Why are additional inspections of a vehicle necessary if it passes a tailpipe inspection?
    The tailpipe test alone cannot guarantee that a care is not emitting harmful amounts of pollutants into California's air. The visual and functional inspections of a vehicle's emission control components and system ensures that the vehicle has all required equipment and that the systems are working properly. These inspections also help prevent evaporative emissions. These types of emissions are created even when the vehicle is not operational. The visual and functional tests also help identify vehicles with tampered (i.e. missing, modified, or disconnected) emissions control systems. These vehicles may be configured to pass the tailpipe portion of the Smog Check, but altered later to produce more emissions than allowed.
  • How can I be sure of my vehicle's Smog Check results?
    All Smog Check equipment must be certified by BAR and meet stringent accuracy standards. Additionally, BAR certified Smog Check equipment requires calibration every three days. If the Smog Check equipment is not calibrated within that period of time, the equipment will not allow any further tests to be performed until a full calibration is complete. In addition, if the equipment experiences any type of system failure, it will automatically lock out the Smog Check inspector from conducting further tests until a representative of the equipment manufacturer has identified and corrected any problems.
  • Can the inspector refuse to test my vehicle for any reason?
    Yes. The inspector is authorized to refuse a vehicle that is determined to be unsafe to test.
  • What is On-Board Diagnostics II?
    On-Board Diagnostics (OBD) II is the second generation of self-diagnostic equipment requirements for California certified vehicles. On-board diagnostic capabilities are incorporated into the hardware and software of a vehicle's on-board computer to monitor virtually every component that can affect emission performance. OBD II systems routinely check each component to verify that it is functioning properly. If a problem or malfunction is detected, the OBD II system illuminates a warning light on the vehicle instrument panel to alert the driver. This warning light typically displays the phrase "Check Engine" or "Service Engine Soon." The system also stores important information about the detected malfunction so that a licensed Smog Check repair technician can accurately find and fix the problem.
  • Who can I contact if I am not satisfied with the testing or repair of my vehicle?
    If you have concerns about the testing or repair of your vehicle, visit our complaint page or contact the Department of Consumer Affairs at (800) 952-5210.
  • How can I be sure a Smog Check inspector or repair technician has had proper training?
    Inspectors and technicians are licensed by BAR to perform emissions testing and/or repairs after meeting certain educational and experience requirements, and then passing a written exam. Continuing education is required for inspectors and repair technicians to maintain their license. To be sure the individual inspecting or repairing your car is licensed by BAR, look at his or her license posted in the station. The license contains the licensee's photograph. You can also verify a license and check to see if there are any disciplinary actions against the licensee by checking online here.
  • Does my vehicle need to have a Smog Check if I am in the military and stationed in California?
    Yes. This requirement is independently enforced by each military base. Generally, military personnel must obtain a passing Vehicle Inspection Report (VIR).
  • What is a VIR?
    A Vehicle Inspection Report (VIR) is provided by a Smog Check station to a vehicle owner upon completion of a Smog Check. This VIR provides details on the tests performed during the inspection. It is not necessary to provide this document to DMV, but it should be kept as evidence of a passing inspection.
  • What if my vehicle's engine or emission control components have been modified from their original design?
    In general, state and federal law prohibit modifications to your vehicle's emission control system. When repairing your vehicle, the emission-related parts used must be original equipment manufacturer (OEM) parts or be replacements for the OEM parts, as specified by the part manufacturer. Modifications to your emissions controls are not acceptable unless the parts used are approved by ARB. ARB grants approvals in cases where the changes or aftermarket parts do not modify the performance of the emission controls in a way that increases emissions. ARB assigns the approved parts an "executive order" (EO) number that may be used to verify acceptability. ARB provides a listing of EO exempted parts on their Web site at Minor changes that do not affect the connectivity with or operation of other emission controls are acceptable. For example, the installation of an universal replacement hose in place of a preformed hose would be allowed.
  • Can I change the engine in my vehicle?
    An engine change may not be performed if it degrades the effectiveness of a vehicle's emissions control systems. For more information, see BAR's Engine Change Guidelines.
  • What if DMV has not received the electronic certificate when I attempt to register my vehicle?
    If you are going to register your vehicle in person at a Department of Motor Vehicles (DMV) field office, be sure to bring your Vehicle Inspection Report (VIR) and any notices sent by DMV with you. The VIR indicates whether your car passed or failed the Smog Check and includes an identification number to help DMV track your electronic certificate, if necessary.
  • Do I need a Smog Check if I'm planning to register my vehicle as non-operational?
    No. A Smog Check is only required every other year upon registration renewal for a vehicle that the owner intends to operate in California. However, if you register a vehicle as non-operational, but then at a later time wish to bring the vehicle back to operational status, a smog inspection may be required.
  • What do I do if I received a "Notice of Incomplete Registration" from DMV?"
    DMV sends motorists this notice when it cannot locate a Smog Check certificate for a vehicle. If you receive one of these notices, you may do one of two things: (1) If you have not yet completed a Smog Check, do so. Once DMV receives an electronic certificate of compliance, the DMV database will be updated and your registration and license plate sticker will be issued. No further action is required on your part. (2) If you have already successfully completed a Smog Check, please allow 30 days to receive your registration and sticker. If, after 30 days, you still have not received your registration and license plate sticker, contact DMV for further assistance.
  • My renewal notice says my vehicle needs a Smog Check but the vehicle is located out of state and will not be back for many months. It's too far to bring back to California for a smog inspection. Can I get my vehicle tested in another state and send the results to DMV?
    No. There is no need to get a smog inspection in another state, as it will not be valid in California. In order to complete your registration, simply fill out and sign DMV's Statement of Facts form stating the reason why the vehicle cannot be tested. DMV will mail the registration and license plate sticker to wherever the car is currently located.
  • Do I need a Smog Check if I'm selling my vehicle and recently had it tested to renew its registration in California?
    California Vehicle Code section 4000.1(d)(1) specifies that a Smog Check certificate is not needed upon changing ownership if the application for transfer is submitted to DMV within 90 days of the vehicle receiving a Smog Check certificate. Therefore, if your vehicle received certification of a passing Smog Check within 90 days of the sale, another Smog Check certificate is not required to transfer ownership.
  • Who is responsible for getting a Smog Check performed when a vehicle is being sold?
    California Vehicle Code section 24007(b)(2) states that it is the responsibility of the seller to provide a valid smog certificate at the time of delivery of the vehicle to the buyer.
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