Certificate Blocking

Assembly Bill (AB) 2289 (Eng, Chapter 258, Statutes of 2010) authorized the Bureau of Automotive Repair (BAR) to prevent the issuance of a Smog Check certificate during an inspection if the On-Board Diagnostic (OBD) data from the vehicle did not correspond with data expected for the vehicle.

AB 2289 amended Health and Safety (H&S) Code section 44036(b)(3)(K) to authorize BAR to develop a real-time computer data program that prevents a certificate of compliance from being issued if a vehicle is identified as having an excessive variance from computer data for that vehicle, mismatched information, or other irregularities. In addition, the legislation foresaw the need for identified vehicles to be directed for further inspection, as described in H&S Code section 44015(a)(2), which prohibits a licensed Smog Check station from issuing a certificate of compliance to an identified vehicle.

In February 2017, BAR began implementation of a data check and certificate blocking program to fulfill these mandates. BAR structured the program as follows:

  • BAR collects and characterizes OBDII inspection data for similar vehicles across the state and creates a “vehicle fingerprint.” Each vehicle inspected is then compared in real time to the established vehicle fingerprint.

  • Stations from which inspection data shows patterns of irregular or mismatched computer data are monitored.

  • Inspections with irregular data at these stations are blocked from issuing a certificate and the vehicle is directed to a referee for inspection. Inspections that do not contain irregular data are not blocked, and therefore will pass the inspection.

  • When a vehicle’s certificate of compliance is blocked, the motorist is notified on the Vehicle Inspection Report (VIR) that the inspection resulted in a “Data Fail.” The VIR indicates that a referee inspection is required to obtain a certificate of compliance. The vehicle’s test history page on BAR’s website is updated with the information so that potential buyers can be better informed prior to purchasing a referee-directed vehicle.

  • Once a referee-directed vehicle is certified, the vehicle can return to a Smog Check station on its next inspection cycle.

Since implementation, approximately 500 stations have had vehicles blocked and redirected to a referee for certification. In conjunction with this effort, BAR has filed approximately 500 administrative cases against stations and inspectors found to have performed OBD clean-plugging inspections of vehicles.

Certificate blocking has been effective in deterring fraudulent Smog Check activity. BAR will continue to protect consumers, improve California’s air quality, and ensure a fair and competitive business climate for stations and inspectors in California’s Smog Check Program.


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