Abstract: A computer-implemented method for detecting a fault in a selective catalytic reducer assembly of an internal combustion engine system includes: receiving, by processing circuitry of a computer system, upstream pressure information indicative of an exhaust gas pressure at a position upstream the diesel particulate filter, as seen in an intended direction of flow from the internal combustion engine to the diesel particulate filter; receiving, by the processing circuitry, pressure difference information indicative of a pressure difference across the diesel particulate filter; and using, by the processing circuitry, the upstream pressure information and the pressure difference information to determine whether or not a fault has occurred in the exhaust selective catalytic reducer assembly.

Abstract: A computer-implemented method for detecting and reducing the amount of urea crystals in an exhaust aftertreatment system including at least one NOx sensor upstream of a urea injector is provided, The method includes: acquiring measurement values from the NOx-sensor; determining lambda values associated with the measurement values, wherein a lambda value being indicative of a ratio between an amount of air and an amount of fuel in a combustion chamber of an engine connected to the exhaust aftertreatment system; determining at least one ratio between the measurement values and the inverse of the determined lambda values, when the ratio between the measurement values and an inverse of the determined lambda values is equal to or exceeds a threshold, using a NOx engine emissions model for urea dosing control in the exhaust aftertreatment system.