Disclosed is a method for diagnosing a first exhaust treatment component for treatment of an exhaust gas stream comprising means for oxidizing nitric oxide into nitrogen dioxide. A first reduction catalytic converter is arranged upstream said means for oxidizing nitric oxide into nitrogen dioxide, and a second reduction catalytic converter is arranged downstream said means. A reagent is for reduction of nitrogen oxides in said first catalytic converter, and a first sensor measures an occurrence of nitrogen oxide downstream said means but upstream said second reduction catalytic converter. The method comprises: causing a supply of reagent upstream said first reduction catalytic converter to an extent exceeding the extent to which reagent is consumed by the first reduction catalytic converter, determining a first measure of the occurrence of reagent downstream said means for oxidizing, and diagnosing said means for oxidizing nitric oxide into nitrogen dioxide based on said first measure.

A safety device intended to detect a leakage in a dry area of an automotive liquid used in a fluid circuit onboard a vehicle, the automotive liquid containing at least one dangerous substance other than water, such as urea, the device including a detection cell sensitive, on the one hand, to the presence of a liquid in the dry area and, on the other hand, to the possible dangerous substance content of the liquid, the device also including a selective analysis unit, capable of distinguishing on the one hand whether the detection cell is in the presence of a liquid or not, and on the other hand, in the presence of liquid, whether the present liquid corresponds to the automotive liquid containing the dangerous substance or to another liquid, called neutral liquid, such as a water condensate.

A work vehicle includes an engine, a battery, an exhaust gas purification system or device, and a notification device. The exhaust gas purification system or device is capable of performing a purification process purifying exhaust gas of the engine, and operates with electric power from the battery and performs an end process. The notification device provides notification that the exhaust gas purification system or device is performing the end process or that the end process is completed.

An on-board vehicle computer system is configured to detect a condition of a vehicle; identify a de-rate cause for the vehicle in a hierarchical set of de-rate causes, wherein the de-rate cause is associated with the condition; select a de-rate type from a set of possible de-rate types based at least in part on the de-rate cause; select an initial de-rate level from a set of possible de-rate levels based at least in part on the de-rate cause; present an operator notification associated with the de-rate cause via an operator interface; activate a de-rate for the vehicle according to the de-rate type and the initial de-rate level; detect a change in the vehicle condition; and update the initial de-rate level based at least in part on the change in the vehicle condition.

A fault diagnosis device for an exhaust pipe fuel injector that diagnoses a normality or an abnormality of the exhaust pipe fuel injector which injects a fuel according to an instructed fuel injection amount, includes: a storage unit which stores a regeneration duration and an instructed fuel injection amount in the regeneration duration; a calculation unit which calculates an instructed fuel injection amount per unit time in the regeneration duration; and a fault diagnosis unit which diagnoses that the exhaust pipe fuel injector is abnormal when the instructed fuel injection amount per unit time in the regeneration duration exceeds a fault threshold, and diagnoses that the exhaust pipe fuel injector is normal when the instructed fuel injection amount per unit time in the regeneration duration does not exceed the fault threshold.

The present disclosure describes methods for evaluating quality of DEF dosed to an EAS including a close coupled SCR unit a downstream SCR unit. A NOx conversion efficiency of the close coupled SCR unit and a NOx conversion efficiency of the downstream SCR unit are used to evaluate quality of DEF. In some embodiments, the NOx conversion efficiency of close coupled SCR unit is used to evaluate quality of DEF. Operation of an EAS using the results of the evaluation of quality of DEF are described.

A reduction-causing agent supply device includes a tank to store a reduction-causing agent, a pumping unit to pump the reduction-causing agent, a reduction-causing agent supply passage to supply the reduction-causing agent, an injection nozzle to inject the reduction-causing agent into an exhaust pipe, a drawing-back unit to draw the reduction-causing agent toward the tank, and a controller. After stop of an engine, the controller performs: reduction-causing agent drawing-back process of drawing the reduction-causing agent toward the tank and introducing exhaust gas from the injection nozzle into the reduction-causing agent supply passage; and gas discharge process of supplying the reduction-causing agent to compress the exhaust gas inside the reduction-causing agent supply passage, discharging the compressed exhaust gas from the injection nozzle, and closing a valve of the injection nozzle before the reduction-causing agent reaches the injection nozzle.

Various embodiments include a method for monitoring the tank content of a storage tank comprising: metering a fluid from the tank into the exhaust gas tract, wherein the fluid has a concentration with respect to a reducing agent; acquiring a current concentration value for the reducing agent; calculating a change in concentration of the reducing agent on the basis of the current concentration value in comparison with a stored concentration value; determining a current operating state of the vehicle to identify an operating state in which refueling cannot be carried out; and carrying out a plausibility check of the calculated change in concentration if the calculated change in concentration exceeds a predetermined threshold value and the operating state is identified. The plausibility check includes acquiring the current tank filling level of the fluid.

The invention relates to a liquid reservoir (1), in particular for an aqueous urea solution, comprising a buffer storage means (2) arranged on the bottom of the liquid reservoir (1) in the installation position, a liquid delivery unit (3), at least one, preferably a plurality of first filter elements (4) arranged on the bottom in the installation position outside the buffer storage means (2), each of which first filter elements is connected to the liquid delivery unit (3) via a liquid line (5), the first filter elements (4) being constructed such that the filter fabric of the first filter elements (4) is permeable to the liquid located in the liquid reservoir (1) and impermeable to air, a second filter element (6) being arranged between the interior of the buffer storage means (2) and the liquid delivery unit (3), which second filter element is constructed such that the filter fabric of the second filter element (6) is permeable to the liquid located in the liquid reservoir (1) and impermeable to air, the breakthrough pressure of the second filter element (6), at which air is delivered through the filter element, being greater than the breakthrough pressure of the first filter elements (4), furthermore comprising a first valve (7) between the liquid delivery unit (3) and the first filter elements (4), the opening pressure of the first valve (7) being smaller than the breakthrough pressure of the second filter element (6).

Selective catalytic reaction (SCR) failure detection systems and methods for propulsion systems. The method includes obtaining (a) an upstream (of the SCR unit) NO.sub.x concentration value, and (b) a downstream NO.sub.x concentration value, and caching (a) and (b). The obtaining and caching is repeated until N cached values are obtained, where N is a preprogrammed number. Using the N cached values, an upstream average of NO.sub.x, an upstream standard deviation, a downstream average of NO.sub.x, and a downstream standard deviation are calculated. The calculated values are input for a failure detection algorithm pertaining to nitrogen oxides (NO.sub.x) that generates a linear correlation factor. A best performing unacceptable (BPU) part is detected when the linear correlation factor is greater than a preprogrammed fail threshold.