Method for diagnosing oxygen sensor fault in vehicle involves deactivating diagnosis process if temperature of converter is higher than predetermined temperature and mass of air flow through converter is smaller than predetermined mass

摘要

The method involves determining temperature of a three-path catalytic converter (136) by a mathematical model and a temperature sensor. A mistake in an oxygen sensor (152), and/or the catalytic converter is diagnosed based on an input received from the oxygen sensor. The diagnosis process is deactivated if the temperature of the converter is higher than predetermined temperature and a total mass of an air flow through the converter is smaller than a predetermined mass, where the total mass is set to zero if an input is received from a diagnosis customer service tool.