Patent ID: 8870987

Claim:
A failure detecting apparatus for detecting failure of a particulate filter which is provided in an exhaust gas passage of an internal combustion engine and which traps particulate matters contained in an exhaust gas, the failure detecting apparatus for detecting the failure of the particulate filter comprising: a PM sensor which detects an amount of particulate matter contained in the exhaust gas allowed to outflow from the particulate filter; an electric control unit including logic that, when executed, performs the steps of: executing a filter regeneration process for oxidizing and removing particulate matter deposited in the particulate filter; and judging that the particulate filter is in the failure state if a decreased amount of the amount of particulate matter contained in the exhaust gas detected by the PM sensor, during a predetermined period of time as started from a point in time at which the filter regeneration process is completed, is not equal to or larger than a predetermined reference amount; wherein the predetermined period of time is the period of time including at least a part of the period of time in which PM trapping efficiency is raised as the time elapses if the particulate filter is normal.