Catalyst Monitor Execution
WARNING: This page is about a different car, the 2011 Mercury Milan, 2011 Lincoln MKZ, 2011 Ford Fusion, 2010 Mercury Milan, and 2010 Ford Fusion. However, it is still accessible from the selected car via links, so may be relevant.
Catalyst monitor execution is once per drive cycle. Typical monitor duration is 10-20 seconds. In order for the catalyst monitor to run, the HO2S monitor must be complete and the EVAP system functional with no stored DTCs. If the catalyst monitor does not complete during a particular drive cycle, the already accumulated switch/signal data is retained in the KAM and is used during the next drive cycle to allow the catalyst monitor a better opportunity to complete.