The STAR program eliminates the tailpipe test requirement for all vehicles 2000 or later. The elimination of the tailpipe test requirement was based on analysis from the California Air Resources Board which showed that tailpipe testing was not as effective as OBD II testing. The benefit to the consumer is that smog tests should be less expensive and take less time. As the STAR program is just being rolled out the true impact on the consumer is yet to be seen.
What is OBD II?
OBD II is an acronym for On-Board Diagnostics II, the second generation of on-board self-diagnostic equipment requirements for California 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. Each component is checked by a diagnostic routine 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 will typically display the phrase "Check Engine" or "Service Engine Soon." The system will also store important information about the detected malfunction so that a repair technician can accurately fix the problem and find.
Can't I Just Reset the Computer and Pass the Smog Test
Many technicians know that if you reset the OBD II computer, that bad readings will no longer be present. The smog check machines now will not allow a vehicle to pass if certain readings are empty. What this means is that if you have recently had your car repaired, or your car has issue with your electrical system or battery these values may be reset, you may not be able to have and OBD II only test.
How is Smog Check affected by OBD II?
In all areas of the state, technicians are required to perform an OBD II check (functional and visual) during the Smog Check inspection. Specifically, the technician visually checks for a functioning and an illuminated warning light and the Smog Check test equipment communicates with the on-board computer for fault information. If a fault is currently causing the light to be on, you need to have the malfunctioning component repaired before you can pass the test.
If codes required for the smog check are empty, the vehicle will need to be driven more before the vehicle can be tested. If the incomplete readiness flags were most likely not a result of a recently disconnected/replaced vehicle battery, or if the vehicle owner does not normally drive the vehicle that often, then the vehicle owner should seek technician help in setting the flags. In the future, OBD II-equipped vehicles may not even have to undergo a tailpipe test.
If you need to have your car smog tested you can find a STAR smog station in your area at this site.