Abstract: In a method for the diagnosis of an exhaust gas aftertreatment system for an internal combustion engine, the exhaust gas aftertreatment system comprises at least one NOx storage catalytic converter (10) and at least one SCR catalytic converter (30) which is arranged downstream of the NOx storage catalytic converter (10). According to the invention, a regeneration of the NOx storage catalytic converter (10) is blocked and/or interrupted in order to improve the frequency and/or quality of the diagnosis of the SCR catalytic converter (30).

Abstract: In the case of a method for checking the plausibility of a NOx sensor (62; 63) in an SCR catalytic converter system having at least one first SCR catalytic converter device (20) and having at least one second SCR catalytic converter device (30) and having in each case one dosing point (40, 50) for a reducing agent solution for the SCR catalytic converter devices (20, 30) upstream of the respective SCR catalytic converter device, the NOx sensor (62) to be checked for plausibility is situated either between the first SCR catalytic converter device (20) and the second SCR catalytic converter device (30), or the NOx sensor (63) to be checked for plausibility is situated downstream of the second SCR catalytic converter device (30).

Abstract: In the case of a method for operating an exhaust gas aftertreatment system of a motor vehicle, the exhaust gas aftertreatment system comprises at least one NOx storage catalyst (10) and at least one SCR catalyst (30). According to the invention, when an inadequate function of the NOx storage catalyst (10) or of the SCR catalyst (30) is identified, at least one auxiliary measure is initiated which leads to a reduction of the NOx emissions of the motor vehicle.

Abstract: In a method for the diagnosis of an exhaust gas aftertreatment system for an internal combustion engine, the exhaust gas aftertreatment system comprises at least one NOx storage catalytic converter (10) and at least one SCR catalytic converter (30) which is arranged downstream of the NOx storage catalytic converter (10). According to the invention, a regeneration of the NOx storage catalytic converter (10) is blocked and/or interrupted in order to improve the frequency and/or quality of the diagnosis of the SCR catalytic converter (30).

Abstract: In the case of a method for checking the plausibility of a NOx sensor (62; 63) in an SCR catalytic converter system having at least one first SCR catalytic converter device (20) and having at least one second SCR catalytic converter device (30) and having in each case one dosing point (40, 50) for a reducing agent solution for the SCR catalytic converter devices (20, 30) upstream of the respective SCR catalytic converter device, the NOx sensor (62) to be checked for plausibility is situated either between the first SCR catalytic converter device (20) and the second SCR catalytic converter device (30), or the NOx sensor (63) to be checked for plausibility is situated downstream of the second SCR catalytic converter device (30).

Abstract: In a method for diagnosing an SCR catalyst system of an internal combustion engine, the SCR catalyst system comprises at least one first SCR catalyst device (20) and at least one second SCR catalyst device (30). A first injection position upstream of the first SCR catalyst device (20) in the form of a first metering device (40) is provided for injecting liquid reducing agent for the SCR catalyst devices (20, 30). A second injection position between the two SCR catalyst devices (20, 30) in the form of a second metering device (50) is furthermore provided. Both SCR catalyst devices (20, 30) are monitored in a differentiated way by means of active and passive diagnostic methods.

Abstract: The present invention relates to a method for monitoring a pollutant conversion capacity of a catalytically coated, oxidizing exhaust gas aftertreatment component (29) in an exhaust gas system (13) of an internal combustion engine (15). A nitrogen oxide sensor (31, 32) is disposed in each case in the flow path of the exhaust gas upstream of and downstream of the oxidizing exhaust gas aftertreatment component (29), a capacity of said oxidizing exhaust gas aftertreatment component (29) for converting NO to NO2 being ascertained from a comparison of the two signals (Z?, Z?) of the nitrogen oxide sensors (31, 32). Additional independent claims relate to an open-loop and/or closed-loop control device (17), a computer program and a computer program product.

Abstract: A method for monitoring a pollutant conversion capacity of a catalytically coated, oxidizing exhaust gas after-treatment component in an exhaust gas system of an internal combustion engine, wherein a capacity of the catalytic coating of the exhaust gas after-treatment component for oxidizing NO to NO2 is ascertained from the degree of efficiency of a downstream SCR catalytic converter, characterized in that operating conditions for said exhaust gas after-treatment component are set such that the effects on the SCR catalytic converter are maximized.

Abstract: In a method for monitoring an SCR catalyst, in particular for monitoring the storage capacity of the SCR catalyst for ammonia, superstoichiometric metering (69) of reducing agents into the SCR catalyst is performed for diagnostic purposes, and the storage capacity of the SCR catalyst is inferred in accordance with at least one characteristic value, which is dependent on the nitrogen oxide conversion rate of the SCR catalyst. In this method, a conditioning phase (67) for setting a specifiable operating point (68) is carried out before the superstoichiometric metering (69) of reducing agents.

Abstract: The present invention relates to a method for operating an exhaust gas aftertreatment apparatus (13) of an internal combustion engine (11), which comprises an oxidation catalytic converter (29), an SCR catalytic converter (35) and a first temperature sensor (32) disposed in the direction of flow downstream of the oxidation catalytic converter (29) and upstream of the SCR catalytic converter (35), an exhaust gas atmosphere capable of exothermal reaction in said oxidation catalytic converter (29) being generated by the metering of hydrocarbons into the exhaust gas (3) upstream of said oxidation catalytic converter (29) during a heating operation.

Abstract: A method for monitoring a nitrogen oxide storage catalytic converter (NSC) in the exhaust gas duct of an internal combustion engine which is operated at least temporarily in a lean fashion, wherein during a lean mode of the internal combustion engine nitrogen oxides from the exhaust gas are stored by the nitrogen oxide storage catalytic converter, wherein during a regeneration phase of the nitrogen oxide storage catalytic converter the internal combustion engine is operated in a rich fashion, and as a result the nitrogen oxides stored in the nitrogen oxide storage catalytic converter are removed, and wherein an exhaust gas component or exhaust gas characteristic variable which is characteristic of the profile of the regeneration is detected during the regeneration phase by means of an exhaust gas probe.

Abstract: A method for diagnosing a metering valve for metering a reagent into the exhaust gas region of an internal combustion engine. The metering valve is actuated by a pulse-width-modulated metering valve actuation signal with a certain duty factor for setting the metering rate. A reagent pump places the reagent at a reagent pressure, and the reagent pump is operated with a pulse-width-modulated pump actuation signal with a certain duty factor. Diagnosis of the metering valve is carried out on the basis of an evaluation of the increase in the metering valve actuation signal pulse duty factor after a predefined increase in the metering rate. The reagent filling level of an SCR catalytic converter arranged in the exhaust gas region is taken into account. At the start of the diagnosis, the reagent storage capacity of the SCR catalytic converter is checked.

Abstract: A method for monitoring the enabling of a system which is assigned to an internal combustion engine, in which the readiness for operation of the system is dependent on an operating temperature, is characterized in that a fault in the enabling of the system is inferred (106) if operation of the system cannot be detected on expiry of a predeterminable time period after the starting of the internal combustion engine or on the recurrence of readiness for operation.

Abstract: A method for operating an exhaust gas system for an internal combustion engine, in which the exhaust gas system includes at least one first catalytic coating and at least one second catalytic coating, the second catalytic coating being situated in the exhaust gas flow downstream from the first catalytic coating. An additional quantity of hydrocarbons is occasionally introduced into the exhaust gas upstream from the first catalytic coating so that a heat-generating reaction may take place in the second catalytic coating. With the aid of at least one temperature sensor and/or at least one hydrocarbon sensor and/or at least one lambda sensor upstream and/or downstream from the second catalytic coating, at least one property of the exhaust gas is ascertained which characterizes a reaction of the second catalytic coating due to the additional quantity of hydrocarbons.

Abstract: A method for acquiring information from a driving operation of a vehicle, in which first information is acquired with respect to at least one operating state of the vehicle and additional second information is ascertained with respect to this at least one operating state using statistical methods, the first and second information concerning this at least one operating state being stored. A method for the assigning and diagnosis of at least one operating state of a vehicle, a control unit, a computer program and a computer-program product are also provided.

Abstract: A method for operating an exhaust system of an internal combustion engine, wherein nitrogen oxide (NOx) is reduced by use of a SCR catalytic converter and wherein the ageing state of the SCR catalytic converter is monitored, characterized in that during a temporally limited phase having a high proportion of nitrogen oxide (NOx) in the exhaust gas, a conversion of said SCR catalytic converter is acquired and evaluated and the ageing state of said SCR catalytic converter is suggested therefrom.

Abstract: A method for monitoring a nitrogen oxide storage catalytic converter (NSC) in the exhaust gas duct of an internal combustion engine which is operated at least temporarily in a lean fashion, wherein during a lean mode of the internal combustion engine nitrogen oxides from the exhaust gas are stored by the nitrogen oxide storage catalytic converter, wherein during a regeneration phase of the nitrogen oxide storage catalytic converter the internal combustion engine is operated in a rich fashion, and as a result the nitrogen oxides stored in the nitrogen oxide storage catalytic converter are removed, and wherein an exhaust gas component or exhaust gas characteristic variable which is characteristic of the profile of the regeneration is detected during the regeneration phase by means of an exhaust gas probe.

Abstract: A method for monitoring the capability of a catalytic converter to convert nitrogen monoxide into nitrogen dioxide in the exhaust gas of an internal combustion engine, the catalytic converter being arranged in an exhaust gas duct of the internal combustion engine and the catalytic converter being followed downstream by a collecting particle sensor. It is in this case provided that, in a monitoring cycle, a decrease in the particle loading of the particle sensor during the operation of the internal combustion engine under predetermined operating conditions is taken to conclude an adequate capability of the catalytic converter to convert from nitrogen monoxide to nitrogen dioxide.

Abstract: A process for monitoring a conversion capacity of a particulate filter arranged in an exhaust gas duct of an internal combustion engine to oxidize nitrogen monoxide to nitrogen dioxide over a catalytic coating includes determining a flow resistance of the particulate filter and setting a temperature of the exhaust gas upstream of the particulate filter. A threshold for a change in the flow resistance of the particulate filter is defined. The monitoring process determines that inadequate conversion capacity of the catalytic coating of the particulate filter is reached when a change in the flow resistance of the particulate filter does not reach the defined threshold within a given period of time.

Abstract: A procedure to diagnose a particle filter disposed in an exhaust gas area of an internal combustion engine as well as a device to implement the procedure is proposed. Provision is made to ascertain the degree of efficiency of the particle filter on the basis of the upstream particle flow occurring upstream in front of the particle filter and on the basis of the downstream particle flow occurring downstream behind the particle filter. The ascertainment of the degree of efficiency of the particle filter allows for an On-Board-Diagnosis of the particle filter, with which compliance with specified exhaust gas threshold values can be assured.