Patent ID: 8176726
Filing Date: 2012-05-15
Classification: B01D,F01N,Y02T

Abstract:
1. A method for introducing a reagent medium into an exhaust gas conduit of an internal combustion engine, in which at least one pressure sensor is provided, the method comprising: performing a diagnosis of the pressure sensor, which is at least for detecting the reagent pressure and which provides a pressure signal; checking, in at least one first time interval, predetermined by a timer, in which an operating pressure is expected, whether a pressure signal at least substantially corresponds to a steady-state pressure; checking, in at least one second time interval, predetermined by the timer, which is in the period following a controlling, during which the internal combustion engine is already switched off, and in which a pressure decrease is expected, a check is performed as to whether the pressure signal at least one of (a) at least substantially corresponds to a predetermined test pressure and (b) at least substantially exhibits a predetermined change with respect to the operating pressure; and supplying an error signal if the pressure signal does not correspond to the operating pressure in the first time interval, and if the pressure signal at least one of does not correspond to the predetermined test pressure and does not exhibit the predetermined change in the second time interval.