Method for diagnosing an exhaust component in an exhaust passage for an internal combustion engine of a vehicle

A non-transitory machine-readable storage medium on which is stored a computer program for diagnosing an exhaust component in an exhaust passage for an internal combustion engine of a vehicle, the computer program, when executed by a computer, causing the computer to perform the following steps:

• while the internal combustion engine is running during a driving cycle of the vehicle:
• obtaining measurement values of an emission parameter generated by the exhaust component;
• comparing the values generated by the exhaust component to a predefined emissions compliance threshold;
• responsive to a result of the comparison being that the predefined emissions compliance threshold has been exceeded by a respective one of the generated values generated by the exhaust component, storing current operating parameters of the internal combustion engine at a time of the exceedance and/or during a period immediately following the exceedance, the stored operating parameters thereby characterizing an operating state of the internal combustion engine at the time of the exceedance;
• obtaining a simulation value of the emission parameter generated by a vehicle test bench, resulting from a reproduction, using the stored operating parameters, of the characterized operating state of the internal combustion engine;
• carrying out the diagnosis of the exhaust component based on a comparison between the simulation value and the respective one of the generated values previously generated by the exhaust component;
• and
• activating a check engine light of an instrument panel of the vehicle in response to the diagnosis.

An electronic control unit configured to diagnose an exhaust component in an exhaust passage for an internal combustion engine of a vehicle, the electronic control unit configured to:

• while the internal combustion engine is running during a driving cycle of the vehicle:
• obtain measurement values of an emission parameter generated by the exhaust component;
• compare the values generated by the exhaust component to a predefined emissions compliance threshold;
• and
• responsive to a result of the comparison being that the predefined emissions compliance threshold has been exceeded by a respective one of the generated values generated by the exhaust component, store current operating parameters of the internal combustion engine at a time of the exceedance and/or during a period immediately following the exceedance, the stored operating parameters thereby characterizing an operating state of the internal combustion engine at the time of the exceedance;
• obtain a simulation value of the emission parameter generated by a vehicle test bench, resulting from a reproduction, using the stored operating parameters, of the characterized operating state of the internal combustion engine;
• carry out the diagnosis of the exhaust component based on a comparison between the simulation value and the respective one of the generated values previously generated by the exhaust component;
• and
• activate a check engine light of an instrument panel of the vehicle in response to the diagnosis.