As of the date and time of this post the California BAR smog check regulation allows for one (1) incomplete or not ready readiness monitor for all 2000 & newer gasoline powered vehicles.
All other emission monitors must be "complete' or "ready". Furthermore, the Catalyst Monitor is must be complete if the vehicle previously had any emission defects causing that monitor not to be ready; and the vehicle is (after repairs) being retested.
Due late 2014 - early 2015 however the monitor requirements for the California Emission Inspection will change to the following: (In fact we are right in the middle of this transition now however the BAR has not yet made its official announcement to implement the new Monitor Readiness Requirements)
(A) Gasoline-powered vehicles model-years 1996 through 1999 with more than one (1) incomplete monitor
(B) Gasoline-powered vehicles model-years 2000 and newer with any incomplete monitors, excluding the evaporative system monitor
(C) Diesel-powered vehicles model-years 1998 through 2006 with any incomplete monitors
(D) Diesel-powered vehicles model-years 2007 and newer with any incomplete monitors, excluding the particulate filter system monitor
If your your Chevy Avalanche recently failed at a smog station because a single monitor was not ready it may be possible the BAR has already begun implementing the new Readiness Monitor Requirements in your county.
