METHOD OF DIAGNOSING THE PRESENCE OF AN EXHAUST AFTER-TREATMENT COMPONENT AND A USE OF THE METHOD FOR VEHICLE ON-BOARD DIAGNOSIS

摘要

In a method for diagnosing the presence of an internal combustion engine exhaust aftertreatment component on a vehicle, the exhaust temperature is measured downstream the aftertreatment component continuously over a time period to provide a first temperature signal with fluctuating amplitude. The temperature signal is modified to provide a second modified temperature signal. The first and second temperature signals are compared to detect any significant difference between the signals.