A method for operating a dosing device for metering an additive to an exhaust-gas treatment device includes determining a dosing amount of additive required by the exhaust-gas treatment device in step a). Subsequently, in step b), an operating mode for the dosing device is determined by carrying out at least steps b.1) and b.2). In step b.1), at least one characteristic operating value of at least one component of the dosing device is provided being definitive of a degree of aging of the dosing device. In step b.2), an operating mode for the dosing device is set in dependence on the characteristic operating value from step b.1). In step c), the dosing device is operated with the set operating mode so that the dosing amount required in step a) is supplied to the exhaust-gas treatment device. A motor vehicle having a dosing device is also provided.

A method for operating a delivery device for delivering a reducing agent from a reducing agent tank into an exhaust treatment device of an internal combustion engine of a motor vehicle, includes at least intermittently carrying out a ventilation process of the delivery device during operation of the internal combustion engine. A registration of a ventilation process first occurs. A timing unit having a preset time interval and/or a mass-flow summing unit having a preset total mass flow is then actuated. When the preset time interval and/or the preset total mass flow is reached, the ventilation process is then carried out. In particular, monitoring the delivery device by a pressure sensor can thus be omitted. A delivery device for delivering a reducing agent is also provided.

A connection head for being arranged in an orifice of a fluid tank with a return cavity in the form of a radial duct is provided. The return cavity overcomes the problems of the formation of air bubbles in the tank and enhances the functioning of the sensor in the tank.

A method for determining an amount of liquid removed from a tank per unit time includes discontinuously feeding the liquid to exhaust gas of an internal combustion engine by at least feeding the liquid through an injection line into the exhaust gas, measuring pressures simultaneously at least at two points in the injection line and determining an amount of liquid fed in per unit time from the measured pressures. The amount of liquid removed between a first point in time and a second point in time is further derived by integrating the amounts of liquid removed per unit time over a period of time from the first point in time to the second point in time. The method allows the precise consumption of the liquid to be calculated and the remaining amount of liquid in the tank to be additionally determined. On-board diagnosis is further possible with the method.

A system and method for utilizing fuel as an on-board reductant for selective catalytic reduction of NOx is provided and includes a controller for controlling an engine to produce a lean first exhaust stream and a rich second exhaust stream that are received in respective first and second passageways of a dual path aftertreatment system. The rich second exhaust stream reacts with NOx stored in a NOx storage and reduction catalyst of the second passageway to regenerate this catalyst and generate ammonia. The first exhaust stream and the second exhaust stream having the generated ammonia are combined in a downstream common passageway to form a combined lean exhaust gas stream where the ammonia carried therein is stored or used by an SCR catalyst of the common passageway for NOx reduction. The engine is subsequently controlled to produce a rich first exhaust stream and a lean second exhaust stream.

A method of determining a volume of a fluid in a reservoir arranged in a vehicle includes assessing, via a controller, whether a first sensor operatively connected to the reservoir and configured to detect a predetermined level of the fluid in the reservoir has been triggered. The method also includes detecting, via a second sensor, a vehicle operative state indicative of inclination of a free surface of the fluid in the reservoir. The method additionally includes communicating, via the second sensor, the detected vehicle operative state to the electronic controller and determining a degree of inclination of the free surface of the fluid in response to the detected vehicle operative state. Furthermore, the method includes determining, via the controller, the volume of the fluid in the reservoir when the first sensor has been triggered in response to the determined degree of inclination of the free surface of the fluid.

Disclosed is a method for diagnosing functionality of dosing units of a fluid dosing system comprising at least two dosing units, a tank unit for holding a fluid, and a pump unit for pressurizing the fluid for the dosing units. The method comprises determining a first hydraulic stiffness value on the basis of first pressure variations and determining a second hydraulic stiffness value on the basis of said second pressure variations. The first hydraulic stiffness value and second hydraulic stiffness value are compared. In a case where the first hydraulic stiffness value and second hydraulic stiffness value differ to a certain extent, concluding that malfunction of at least one of said dosing units is at hand, and in a case where the first hydraulic stiffness value and the second hydraulic stiffness value do not differ to said certain extent, concluding that the first and second dosing units function as intended.

Tank for a liquid solution based on water and urea which is suitable for being combined with a selective catalytic reduction system. The tank comprises: a container including an upper wall; a filling pipe union which is positioned on the upper wall of the container and which is suitable for introducing the liquid solution; a lower opening, from which the liquid solution being introduced passes into the container and which protrudes with respect to the upper wall towards the interior of the container; a closure float which is positioned in the container and which is connected to the lower opening and which is configured so as to raise and close the lower opening once the liquid solution in the container reaches a predetermined level.

A method for operating a motor vehicle having an exhaust gas aftertreatment device involves an on-board electronic computing device receiving consumption information characterizing consumption of a reducing agent by the exhaust gas aftertreatment device and tank information characterizing a filling level of a reducing agent tank. Tank information is evaluated together with the consumption information with regard to a divergence, and upon determination of the divergence between the tank information and the consumption information, error information is stored in a blockchain characterizing the motor vehicle, and an action of the motor vehicle is triggered.

Disclosed is a liquid storage container which has an inspection window to check the completely filled state of the liquid storage container with a liquid injected thereinto and inhibit occurrence of a detection error of an optical concentration sensor due to light flowing into the liquid storage container through the inspection window. The liquid storage container includes a container main body configured to store the liquid, an inlet configured to inject the liquid into the container main body therethrough, the inspection window installed on the container main body and to confirm the completely filled state of the container main body with the liquid, a concentration sensor configured to detect the concentration of the liquid in the container main body, and a light blocking device installed in the container main body to block light entering through the inspection window.